Innovations in Biotechnology and Medical Sciences

Innovations in Biotechnology and Medical Sciences

Omega-3 Fatty Acids and its Health Impacts

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Fatty Acids and their health implications

Why in the News?

  • Fish oil supplements, highly regarded for their high omega-3 fatty acid content, have long been associated with heart health benefits.
    • A recent study has caused controversy by raising the possibility that these supplements may be as harmful as previously thought.

What are Fatty Acids?


Fatty acids are crucial lipids (fats and oils) essential for various biological functions (Fatty Acid + Glycerol = Fats). They are carboxylic acids with a long aliphatic chain, either saturated or unsaturated.

  • Basic Structure: Consists of a hydrocarbon chain with a terminal carboxyl group (-COOH). The length and degree of saturation of the hydrocarbon chain can vary.
  • Roles in the Body: Serve as energy sources, components of cell membranes, and precursors for bioactive lipids.

Types of Fatty Acids

Fatty acids are classified based on the presence and number of double bonds in their hydrocarbon chain:

  1. Saturated Fatty Acids (SFA)
    • Structure: Contain no double bonds between carbon atoms; the hydrocarbon chain is saturated with hydrogen atoms.
    • Properties: Typically solid at room temperature.
    • Sources: Animal fats, coconut oil, palm oil, dairy products.
    • Examples: Palmitic acid, stearic acid.
  2. Monounsaturated Fatty Acids (MUFA)
    • Structure: Contain one double bond in the hydrocarbon chain.
    • Properties: Generally liquid at room temperature but solidify when chilled.
    • Sources: Olive oil, canola oil, peanut oil, avocados, nuts.
    • Examples: Oleic acid.
  3. Polyunsaturated Fatty Acids (PUFA)
    • Structure: Contain two or more double bonds in the hydrocarbon chain.
    • Properties: Liquid at room temperature and in the refrigerator.
    • Sources: Fish, flax seeds, walnuts, sunflower oil, corn oil.
    • Examples:
  1. Omega-3 Fatty Acids: Alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA).
  2. Omega-6 Fatty Acids: Linoleic acid, arachidonic acid.
  1. Trans Fatty Acids
    • Formation: Produced by the industrial process of hydrogenation of unsaturated fats, or naturally in the guts of some animals.
    • Properties: Similar to saturated fats, solid at room temperature.
    • Health Impact: Associated with negative cardiovascular effects.
    • Sources: Margarine, partially hydrogenated oils, and some baked goods.

What are Omega-3 Fatty Acids?

  • Omega-3 fatty acids (omega-3s) are polyunsaturated fats that perform important functions in the human body.
  • There are three main types of omega-3 fatty acids:
    • EPA (eicosapentaenoic acid). EPA is a “marine omega-3” because it’s found in fish.
    • DHA (docosahexaenoic acid). DHA is also a marine omega-3 found in fish.
    • ALA (alpha-linolenic acid). ALA is the form of omega-3 found in plants.
    • When we get ALA from food, the human body can turn some of the ALA into EPA and subsequently to DHA. However, this process provides just a small amount of EPA and DHA. So, dietary sources of EPA and DHA (like fish) are essential.

Functions of Omega-s fatty acids:

    • They help to provide structure and supporting interactions between cells.
    • Omega-3s are concentrated in high levels in cells in human eyes and brain.
    • They provide the human body with energy (calories) and support the health of many body systems.  These include the human cardiovascular system and endocrine system.

Significance of Omega-3 fatty acids:

  • Omega-3 fatty acids have many potential benefits for human cardiovascular health.
  • One key benefit is that they help lower human triglyceride levels.
    • Too many triglycerides in human blood (hypertriglyceridemia) raise human risk of atherosclerosis, and through this, can increase human risk of heart disease and stroke. So, it’s important to keep triglyceride levels under control.
  • Omega-3s may help us by raising human HDL (good) cholesterol and lowering human blood pressure.
    • Some studies show omega-3s may lower human risk for Cardiovascular disease (CVD), and hence lowering the sudden death caused by an abnormal heart rhythm (arrhythmia), and blood clots.
  • Beyond heart health, omega-3s may help lower the human risk of developing some forms of cancer, including breast cancer, Alzheimer’s disease, and dementia, age-related macular degeneration (AMD), research continues to investigate these and other possible benefits.

PYQ:

[2011] A company marketing food products advertises that its items do not contain trans-fats. What does this campaign signify to the customers?

  1. The food products are not made out of hydrogenated oils.
  2. The food products are not made out of animal fats/ oils.
  3. The oils used are not likely to damage the cardiovascular health of the consumers.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

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Innovations in Biotechnology and Medical Sciences

Xenotransplantation: Prospects and Challenges

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Xenotransplantation, Crispr-Cas9

Mains level: NA

Why in the News?

The recent passing away of Richard Slayman, the first recipient of a modified pig kidney transplant, has drawn attention to xenotransplantation—an innovative medical procedure with the potential to revolutionise organ transplantation.

What is Xenotransplantation?

  • It involves transplanting live cells, tissues, or organs from nonhuman animal sources into human recipients.
  • It seeks to address the critical gap between organ demand and supply.
  • Xenotransplantation, pioneered in the 1980s with heart transplants, has emerged as a promising solution to alleviate the organ shortage crisis, particularly prevalent in kidney transplantation.

Examples:

  • Chimpanzee-to-Human Transplants: In the 1960s, there were attempts at chimpanzee-to-human kidney transplants, heart transplants, and liver transplants.
  • Pig-to-Human Heart Transplant: In 2022, a groundbreaking milestone was achieved with the first successful transplantation of a pig heart into a human with end-stage heart disease

Procedural Details

  • Xenotransplantation involves genetic modifications to animal organs, like 69 CRISPR-Cas9 edits to a pig kidney, removing pig genes and adding human genes for compatibility.

Why is the Pig a Preferred Source?

  • Anatomical Resemblance: Pigs are favoured for xenotransplantation due to their physiological similarities to humans, facilitating successful integration. Pig organs, like heart valves, have been used in human medicine for over 50 years.
  • Breeding Advantages: Extensive pig farming ensures a readily available and cost-effective supply of organs, with diverse breeds offering size-matching opportunities.

Challenges associated

  • The main challenge is preventing organ rejection. Innovative methods, such as embedding the pig’s thymus gland under the kidney’s outer layer, help manage immune responses.
  • There are also significant concerns regarding potential infections from both recognised and unrecognised infectious agents that could affect not only the recipient but also the wider population.
  • Retroviruses present in the animal organs pose a risk of cross-species infection, which could remain latent and cause diseases years after the transplantation.

PYQ: 

[2017] With reference to agriculture in India, how can the technique of ‘genome sequencing’, often seen in the news, be used in the immediate future?

  1. Genome sequencing can be used to identify genetic markers for disease resistance and drought tolerance in various crop plants.
  2. This technique helps in reducing the time required to develop new varieties of crop plants.
  3. It can be used to decipher the host-pathogen relationships in crops.

Select the correct answer using the code given below:

(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

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Innovations in Biotechnology and Medical Sciences

X chromosome revival in older Women increases Autoimmune Disease risk

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Autoimmune Diseases, X Chromosome

Mains level: NA

Why in the News?

The X chromosome influences biological functions and disease susceptibilities, affecting genetic disorders, autoimmune diseases, and Alzheimer’s, with research offering potential new treatments and therapies.

Back2Basics: Chromosomes

  • Chromosomes are fundamental components of cells that play a vital role in storing and transmitting genetic information.
  • These structures contain genes, which carry instructions for the development, functioning, and inheritance of traits.
  • Chromosomes consist of tightly coiled DNA molecules wrapped around proteins called histones, forming chromatin.
  • Before cell division, chromosomes replicate into identical sister chromatids held together at the centromere.

Types of Chromosomes:

  1. Autosomes: Non-sex chromosomes (22 pairs in humans) determine most traits.
  2. Sex Chromosomes: Determine biological sex (XX for females, XY for males).

Functions of Chromosomes

  • Genetic Information Storage: Genes on chromosomes encode instructions for protein production and cellular processes.
  • Inheritance: Chromosomes transmit genetic information during sexual reproduction through meiosis, ensuring genetic diversity in offspring.
  • Gene Expression Regulation: Chromosomes control gene activation or silencing, crucial for development and cell functioning.

Genetic Landscape of the X chromosome:

  • The human X chromosome encodes around 800 genes, producing proteins.
  • Loss of function in these genes can lead to various genetic diseases.
  • Diseases influenced by the X chromosome fall into three categories:
  1. X-linked genetic diseases
  2. Diseases influenced by XCI (X chromosome inactivation) escape
  3. Diseases linked to X-chromosome aneuploidy

What is the X chromosome?

  • It is one of the two sex chromosomes in humans, the other being the Y chromosome.
  • Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY).
  • Significance:
    • Encodes around 800 genes that are crucial for various biological processes.
    • Plays a significant role in determining sex and influencing many physiological functions.
    • Loss of function or mutations in X chromosome genes can lead to several genetic disorders.

What are Autoimmune Diseases?

  • Diseases where the immune system mistakenly attacks the body’s own cells and tissues.
  • Normally, the immune system defends against infections by targeting harmful pathogens.
  • Common Autoimmune Diseases:
    • Systemic Lupus Erythematosus (SLE): Chronic inflammation affecting various body parts.
    • Rheumatoid Arthritis (RA): Inflammation of joints and surrounding tissues.
    • Sjogren’s Syndrome: Affects glands that produce moisture, leading to dry mouth and eyes.

How does the X chromosome cause Autoimmune Diseases?

  • X Chromosome Inactivation (XCI):
    • In females, one of the two X chromosomes is randomly inactivated during early embryonic development to balance gene expression between males and females.
    • This process is crucial to prevent overexpression of X-linked genes.
  • XCI Escape:
    • Not all genes on the inactive X chromosome are completely silenced.
    • Up to a fourth of these genes may escape inactivation and continue to be expressed.
  • Link to Autoimmune Diseases:
    • Skewed XCI: Uneven inactivation of X chromosomes may lead to an imbalance in gene expression, contributing to autoimmune disorders.
    • Incomplete XCI: Reactivation of genes that should be silenced can result in abnormal immune responses.

Studies, such as one published in Science Advances (May 3, 2023), have shown that reactivation of X-linked genes in immune cells can lead to lupus-like symptoms in mice.

Linkage between X chromosome and Alzheimer’s disease

  • Sex Bias in Alzheimer’s:
    • Women are almost twice as likely as men to develop Alzheimer’s disease.
  • Role of X-Linked Genes:
    • Researchers have identified a gene called ubiquitin-specific peptidase 11 (USP11) on the X chromosome.
    • USP11 Gene: Involved in protein modification processes and thought to influence the accumulation of tau proteins in the brain.
    • XCI Escape: USP11 may escape XCI in females, leading to higher expression levels and contributing to Alzheimer’s pathology.
    • A study from Case Western Reserve University (Cell, October 2022) highlighted this mechanism, suggesting it as a target for new treatments.

PYQ:

[2011] At present, scientists can determine the arrangement or relative positions of genes or DNA sequences on a chromosome. How does this knowledge benefit us?

  1. It is possible to know the pedigree of livestock.
  2. It is possible to understand the causes of all human diseases.
  3. It is possible to develop disease-resistant animal breeds.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 only

(c) 1 and 3 only

(d) 1, 2 and 3

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Innovations in Biotechnology and Medical Sciences

Decoding C. Elegans Worm: A Remarkable Discovery

Note4Students

From UPSC perspective, the following things are important :

Prelims level: C. Elegans Worm

Mains level: NA

Why in the news?

Researchers at Princeton University found that Caenorhabditis elegans can inherit the ‘knowledge’ to avoid a disease-causing bacterium, Pseudomonas vranovensis, across several generations after initially consuming it.

C. Elegans: Breakthrough made in Scientific Research

  • C. elegans can inherit the ‘knowledge’ to avoid a disease-causing bacterium, Pseudomonas vranovensis, across several generations after by consuming it.
  • The study revealed that the worms ingested small RNA (sRNA) molecules from P. vranovensis, which then altered their feeding behaviour to avoid the bacteria.
  • This sRNA interacts with the worm’s gene maco-1, affecting its neurological functions.
  • These sRNAs are passed down to at least four subsequent generations, demonstrating a form of transgenerational epigenetic inheritance.

 

About C. Elegans Worm

  • C. elegans, or Caenorhabditis elegans, is a small, transparent nematode (roundworm) widely used in scientific research.
  • It is about 1 mm in length, making it easy to study under a microscope.
  • It has a simple body plan, which simplifies many types of biological research.
  • C. elegans was the first multicellular organism to have its entire genome sequenced in 1998.

Key Features of C. Elegans Worm

  • Short lifespan and quick regeneration: It has a short lifespan of about 2-3 weeks and develops from an egg to an adult in just 3-5 days. This allows for quick generation turnover and facilitates studies on genetics and developmental biology.
  • Transparency:  It allows researchers to easily observe its internal structures and developmental processes in real time.
  • Genetic information: This has provided a wealth of genetic information and made it a powerful tool for genetic studies.
  • Consistent Somatic Cell Count: Adult C. elegans have exactly 959 somatic cells, and their lineage has been fully mapped, providing a consistent model for studying cell development and death.

PYQ:

[2021] Consider the following:​

1. Bacteria​

2. Fungi​

3. Virus​

Which of the above can be cultured in artificial/synthetic medium?​

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

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Innovations in Biotechnology and Medical Sciences

CRISPR’s Breakthrough in Treating Blindness

Note4Students

From UPSC perspective, the following things are important :

Prelims level: LCA, CRISPR Cas9;

Mains level: NA

Why in the news?

Scientists have successfully used CRISPR-Cas9 gene editing to restore vision in individuals with a rare form of inherited or congenital blindness.

  • The groundbreaking clinical trial, named “BRILLIANCE,” demonstrated promising results in improving vision and quality of life for participants with Leber congenital amaurosis (LCA), a severe vision disorder.

What is Leber Congenital Amaurosis (LCA)?

  • LCA is a rare genetic disorder that primarily affects the retina the ‘light-sensitive’ tissue at the back of the eye. It leads to severe visual impairment or blindness at birth or within the first few months of life.
  • It is inherited in an autosomal recessive manner, meaning a child needs to inherit one defective gene from each parent to develop the condition.
  • There are several genes associated with LCA, with mutations in at least 14 different genes known to cause the disorder.
  • These genes generally affect the development and function of photoreceptors or the retinal pigment.

Key highlights of the BRILLIANCE trial:

  • The BRILLIANCE trial involved 12 adults and two children diagnosed with LCA, a condition characterized by early-onset vision loss.
  • Participants received a single dose of a CRISPR gene therapy called EDIT-101, designed to correct mutations in the CEP290 gene responsible for LCA.
  • In this case, CRISPR-Cas9 cuts out the faulty DNA segment in the CEP290 gene and replaces it with a healthy DNA sequence, restoring the function of the CEP290 protein crucial for vision.
  • Out of 14 participants, 11 experienced improved vision without serious side effects.

Back2Basics: CRISPR-Cas9 Gene Editing

  • CRISPR-Cas9 stands for Clustered Regularly Interspaced Short Palindromic Repeats and CRISPR-associated protein 9.
  • It is a technology that allows geneticists and researchers to edit parts of the genome by altering sections of the DNA sequence.
  • Emmanuelle Charpentier and Jennifer Doudna’s work on CRISPR-Cas9 as a ‘molecular scissor’ earned them the 2020 Nobel Prize in chemistry.
  • The system consists of two key components:
  1. Cas9: This is the enzyme that acts like a pair of molecular scissors. It is responsible for cutting the DNA strand at a specific location, allowing for the removal, addition, or alteration of DNA at that site.
  2. Guide RNA (gRNA): This is a piece of RNA that is designed to find and bind to a specific sequence of DNA that matches its code. The gRNA guides the Cas9 enzyme to the exact spot in the genome where an edit is desired.
  • Mechanism:
    • The process begins with the design of a gRNA that matches the DNA sequence where an edit is needed.
    • Once inside the cell, the Cas9 enzyme and the gRNA form a complex that can identify and bind to the target DNA sequence.
    • The Cas9 then cuts the DNA at this location.
    • After the DNA is cut, the cell’s natural repair mechanisms can be harnessed to add or remove genetic material, or to make specific changes to the DNA.

 

PYQ:

[2019] What is Cas9 Protein that is often mentioned in news?

(a) A molecular scissors used in targeted gene editing

(b) A biosensor used in the accurate detection of pathogens in patients

(c) A gene that makes plants pest-resistant

(d) A herbicidal substance synthesized in genetically modified crops

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Innovations in Biotechnology and Medical Sciences

Magnetic Resonance Imaging (MRI) and the Science behind

Note4Students

From UPSC perspective, the following things are important :

Prelims level: MRI and its working principle

Mains level: NA

Why in the news?

  • Magnetic Resonance Imaging (MRI) revolutionized medical diagnostics, offering non-invasive insights into soft tissues.
  • The pioneering efforts of Paul Lauterbur and Peter Mansfield led to its commercialization, earning them the Nobel Prize in Medicine in 2003.

What is MRI?

  • Magnetic resonance imaging (MRI) is a non-invasive diagnostic procedure used to obtain detailed images of soft tissues within the body.
  • It is particularly valuable for imaging sophisticated structures like the brain, cardiovascular system, spinal cord, joints, muscles, liver, and arteries.
  • MRI is instrumental in diagnosing and monitoring various conditions, including cancer, neurological disorders (such as Alzheimer’s and stroke), and cardiovascular diseases.
  • Functional MRI (fMRI) can also assess brain activity by monitoring changes in blood flow.

Working Principle:

  • MRI utilizes the magnetic properties of hydrogen atoms (one proton with one electron around it), which are abundant in water and fat molecules found throughout the body.
  • The MRI machine generates a powerful magnetic field, aligning hydrogen atoms within the body.
  • Radiofrequency pulses are then applied, causing hydrogen atoms to absorb energy and emit signals.
  • These emitted signals are detected by sensors and processed by a computer to create detailed images of the body’s internal structures.

Components of an MRI Machine:

The MRI machine consists:

  • Superconducting Magnet: Large magnet (superconducting magnet) that produces a powerful and stable magnetic field.
  • Gradient Coils: Gradient magnets produce smaller magnetic fields with varying strengths and directions, allowing for precise imaging of specific body areas.
  • Radiofrequency Coils: This emit radiofrequency pulses to excite hydrogen atoms in the body. The frequency of pulse the ‘excess’ atoms have to absorb is called the Larmor frequency.
  • Detectors: It capture emitted signals from hydrogen atoms and convert them into image data for analysis.

Advantages of MRI:

  • High-Resolution Imaging: MRI offers high-resolution imaging with excellent tissue contrast, allowing for accurate diagnosis and treatment planning.
  • Versatile Viewing Angles: It can visualize structures from various angles without the need for repositioning, providing comprehensive information.
  • Safety and Non-Invasiveness: MRI scans are non-invasive and do not involve ionizing radiation, making them safe for repeated use.
  • Enhanced Image Quality: Contrast agents can enhance image quality by highlighting specific tissues or abnormalities.

Limitations of MRI:

  • High Costs: MRI machines are expensive to purchase and maintain, resulting in high healthcare costs for patients.
  • Requirement for Patient Stillness: Patients undergoing MRI scans must remain still for extended periods to prevent image distortion, which can be challenging for some individuals.
  • Discomfort or Anxiety: The strong magnetic fields and loud noises produced during MRI scans may cause discomfort or anxiety for patients.
  • Limitations with Metallic Implants: Certain metallic implants or objects can interfere with MRI scans, limiting their use in individuals with such implants.

PYQ:

[2020] With the present state of development, Artificial Intelligence can effectively do which of the following?

  1. Bring down electricity consumption in industrial units
  2. Create meaningful short stories and songs
  3. Disease diagnosis
  4. Text-to-Speech Conversion
  5. Wireless transmission of electrical energy

Select the correct answer using the code given below:

(a) 1, 2, 3 and 5 only

(b) 1, 3 and 4 only

(c) 2, 4 and 5 only

(d) 1, 2, 3, 4 and 5

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Innovations in Biotechnology and Medical Sciences

Role of Fusobacterium in Colorectal Cancer

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Fusobacterium nucleatum animalis (Fna)

Mains level: NA

Why in the news?

  • Researchers at the Fred Hutchinson Cancer Center in the US have identified specific subtypes of Fusobacterium nucleatum associated with colorectal cancer (CRC) tumors.
  • These subtypes, particularly Fusobacterium nucleatum animalis (Fna), have been found in relatively higher quantities in CRC tumors.

About Fusobacterium nucleatum

  • Fusobacterium nucleatum is a species of bacteria commonly found in the human mouth.
  • It is a gram-negative anaerobic bacterium, meaning it does not require oxygen for growth.
  • While typically residing in the oral cavity, it has been associated with various diseases and conditions, including periodontal diseases and colorectal cancer.

Association with Colorectal Cancer (CRC):

  • In cases of colorectal cancer (CRC), Fusobacterium nucleatum has been found within tumors in the gut.
  • Studies have shown that this bacterium can aid cancer cells in evading the immune system and promoting metastasis, or the spread of cancer to other parts of the body.
  • Its presence in CRC tumors has led to investigations into its potential role in the development and progression of colorectal cancer.

Impact:

  • Assisting cancer cells in evading the immune system.
  • Promoting inflammation and creating an environment conducive to tumor growth.
  • Facilitating metastasis by interacting with cancer cells and promoting their spread to other tissues.

PYQ:

[2013] Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as Aflatoxins which are not generally destroyed by normal cooking process. Aflatoxins are produced by:

(a) Bacteria

(b) Protozoa

(c) Moulds

(d) Viruses

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Innovations in Biotechnology and Medical Sciences

West Nile Fever Outbreak in Kerala 

Note4Students

From UPSC perspective, the following things are important :

Prelims level: West Nile Virus, Its host, Transmission;

Mains level: NA

Why in the news?

  • The Kerala government disclosed the re-emergence of West Nile fever cases in Thrissur, Malappuram, and Kozhikode districts.
  • West Nile fever was first detected in Kerala in 2011, with a fatal case recorded in 2019 involving a six-year-old from Malappuram.

What is West Nile Fever?

  • West Nile fever is caused by a West Nile Virus (WNV) transmitted through bites from infected Culex mosquitoes.
  • The WNV is a mosquito-borne, single-stranded RNA virus.
  • According to the WHO, it is a member of the flavi-virus genus and belongs to the Japanese Encephalitis antigenic complex of the family Flaviviridae.

How does it spread?

  • It is transmitted by infected mosquitoes between and among humans and animals, including birds, which are the reservoir host of the virus.
  • Mosquitoes become infected when they feed on infected birds, which circulate the virus in their blood for a few days.
  • The virus eventually gets into the mosquito’s salivary glands.
  • During later blood meals (when mosquitoes bite), the virus may be injected into humans and animals, where it can multiply and possibly cause illness.
  • WNV can also spread through blood transfusion, from an infected mother to her child, or through exposure to the virus in laboratories.
  • It is not known to spread by contact with infected humans or animals.

Symptoms of WNV infection:

  • The disease is asymptomatic in 80% of the infected people.
  • The rest develop what is called the West Nile fever or severe West Nile disease.
  • In these 20% cases, the symptoms include fever, headache, fatigue, body aches, nausea, rash, and swollen glands.

PYQ:

[2017] Consider the following statements:

1. In tropical regions, Zika virus disease is transmitted by the same mosquito that transmits dengue.

2. Sexual transmission of Zika virus disease is possible.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

 


Back2Basics: Type of Viruses 

Subtypes Description Examples
DNA Viruses Herpesviruses DNA viruses with a complex structure causing various diseases including cold sores, chickenpox, and mononucleosis. HSV-1, HSV-2, VZV, EBV
Papillomaviruses DNA viruses associated with warts and certain cancers. HPV
Adenoviruses DNA viruses causing a wide range of infections in humans. Adenovirus types causing respiratory, gastrointestinal, and ocular infections
Poxviruses Large, complex DNA viruses responsible for diseases like smallpox. Variola virus (smallpox), Vaccinia virus
RNA Viruses Positive-Sense RNA Viruses RNA viruses with genomes that can directly serve as mRNA, causing diseases like the common cold, Zika, and COVID-19. Picornaviruses, Flaviviruses, Coronaviruses
Negative-Sense RNA Viruses RNA viruses requiring transcription into positive-sense RNA before translation, causing diseases like influenza and rabies. Orthomyxoviruses, Paramyxoviruses, Rhabdoviruses
Retroviruses RNA viruses that use reverse transcriptase to integrate their genome into the host cell’s DNA. HIV, HTLV
Double-Stranded RNA (dsRNA) Viruses RNA viruses with double-stranded RNA genomes causing gastroenteritis and other infections. Reoviruses
Single-Stranded RNA (ssRNA) Viruses with Ambisense Genome RNA viruses with genomes containing both positive-sense and negative-sense RNA regions. Arenaviruses, Bunyaviruses
Single-Stranded RNA (ssRNA) Viruses with Segmented Genome RNA viruses with genomes consisting of multiple segments, causing diseases like influenza and hemorrhagic fevers. Orthomyxoviruses, Bunyaviruses
Single-Stranded RNA (ssRNA) Viruses with Circular Genome Satellite viruses with a circular RNA genome requiring helper viruses for replication. Hepatitis Delta Virus (HDV)
Enveloped Viruses Influenza Viruses RNA viruses surrounded by a lipid envelope causing seasonal flu outbreaks. Influenza A, B, C viruses
Herpesviruses Enveloped DNA viruses causing diseases like cold sores, chickenpox, and mononucleosis. HSV-1, HSV-2, VZV, CMV
Coronaviruses Enveloped RNA viruses causing diseases like severe acute respiratory syndrome (SARS) and COVID-19. SARS-CoV, MERS-CoV, SARS-CoV-2
HIV Enveloped retroviruses responsible for acquired immunodeficiency syndrome (AIDS). Human immunodeficiency virus
Ebola Virus Enveloped RNA virus causing severe hemorrhagic fever in humans. Ebola virus
Non-enveloped Viruses Adenoviruses DNA viruses lacking a lipid envelope, causing various infections in humans. Adenovirus types causing respiratory, gastrointestinal, and ocular infections
Papillomaviruses DNA viruses associated with warts and certain cancers, lacking an envelope. HPV
Noroviruses RNA viruses causing gastroenteritis, lacking an envelope. Norovirus
Rotaviruses RNA viruses causing severe gastroenteritis in infants and young children, lacking an envelope. Rotavirus
Bacteriophages T4 Bacteriophage Viruses that infect bacteria, with a complex structure and lifecycle. T4 bacteriophage
Lambda Phage Temperate bacteriophage capable of lysogenic and lytic cycles in E. coli. Lambda phage

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Innovations in Biotechnology and Medical Sciences

Endosymbiotic Theory and Symbiogenesis

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Endosymbiotic Theory, Nitrogen Cycle

Mains level: NA

Why in the news?

  • The endosymbiotic theory suggests that tiny structures in cells called mitochondria and chloroplasts were once independent bacteria.
  • A biologist named Lynn Margulis came up with the idea that cells merged with bacteria, challenging the usual belief that evolution happens mainly through genetic changes.

 What is the Endosymbiotic Theory?

  • The endosymbiotic theory proposes that organelles like mitochondria and chloroplasts were once free-living bacteria engulfed by recipient cells.
  • American biologist Lynn Margulis introduced Symbiogenesis, challenging the Neo-Darwinist consensus on genetic mutations driving evolution.
  • Margulis’s Struggle:
  1. Margulis’s manuscript on symbiogenesis faced rejection by academic journals before finally being published in The Journal of Theoretical Biology in 1967.
  2. It took years for mitochondria and chloroplasts to be acknowledged as former free-living bacteria turned endosymbionts.

Recent Discoveries and Endosymbiotic Theory

  • Recent papers published in Science and Cell have reignited interest in the endosymbiotic theory.
  • The focus is on nitrogen fixation, crucial for proteins and DNA in living organisms.
  • Despite abundant atmospheric nitrogen, plants lack the means to utilize it efficiently.
  • Legumes host nitrogen-fixing bacteria in root nodules, aiding in ammonia production for plant use.

Evolution of Nitroplast

  • Cyanobacterium UCYN-A was found in marine algae, establishing a symbiotic relationship.
  • Nitroplast, a new organelle, co-evolved with its host cell, satisfying criteria for organelle classification.
  • Nitroplast integrates into host cell function and architecture, imports host cell proteins, synchronizes growth, and is inherited during cell division.
  • Nearly half of nitroplast proteins are derived from the host cell.

Nitrogen Cycle:


The nitrogen cycle is a crucial biogeochemical cycle that describes the transformation and circulation of nitrogen in various forms within ecosystems. It involves several key steps:

  1. Nitrogen Fixation: This is the process by which atmospheric nitrogen (N2) is converted into ammonia (NH3) or nitrate (NO3-) ions, which are forms of nitrogen that plants can utilize. Nitrogen fixation can occur through biological, atmospheric, and industrial processes. In biological nitrogen fixation, certain bacteria like Rhizobium spp. in the root nodules of leguminous plants or cyanobacteria convert N2 into ammonia.
  2. Ammonification: Ammonification is the process by which organic nitrogen compounds from dead organisms, feces, and other waste materials are converted into ammonia by decomposer organisms like bacteria and fungi during the decay process.
  3. Nitrification: Nitrification is the biological oxidation of ammonia (NH3) or ammonium (NH4+) to nitrite (NO2-) and then to nitrate (NO3-) by nitrifying bacteria such as Nitrosomonas and Nitrobacter. This process occurs in aerobic conditions and plays a crucial role in making nitrogen available to plants.
  4. Assimilation: Plants and other organisms take up ammonia, nitrate, or organic nitrogen compounds from the soil to use them in synthesizing proteins, nucleic acids, and other vital nitrogen-containing compounds.
  5. Denitrification: Denitrification is the process by which nitrate (NO3-) is converted back into nitrogen gas (N2) or nitrous oxide (N2O) by denitrifying bacteria under anaerobic conditions. This step completes the cycle by returning nitrogen to the atmosphere, closing the loop.
  6. Ammonium Ionization: In soils and aquatic environments, ammonium ions (NH4+) may undergo ionization, converting to ammonia gas (NH3), which can volatilize and return to the atmosphere.

Significance of the Nitroplasts

  • Agriculture: Nitroplasts offer potential solutions for reducing the harmful effects of industrial ammonia production.
  • Biotechnology: Biotechnological applications may include engineering host cells and nitroplasts for efficient nitrogen fixation in plants.

PYQ:

[2021] In case of which one of the following biogeochemical cycles, the weathering of rocks is the main source of release of nutrient to enter the cycle?​

(a) Carbon cycle

(b) Nitrogen cycle

(c) Phosphorus cycle

(d) Sulphur cycle

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Innovations in Biotechnology and Medical Sciences

Unveiling the Link between Fairness Creams and Nephrotic Syndrome

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Mercury Poisoning, Membranous Nephropathy, Minamata Convention.

Mains level: NA

Why in the news?

  • Researchers from Kerala reported 15 cases of Membranous Nephropathy (MN) linked to the regular application of fairness creams.
  • These creams contained high levels of mercury, sometimes exceeding the safe limit by 10,000 times.

Mercury Contamination in Hair Cream

  • Blood and urine screenings of affected individuals unveiled alarmingly high levels of mercury, a well-known toxic element.
  • The fairness creams contained mercury levels up to 10,000 times above the permissible limit of 1 ppm under Minamata Convention (2013).
  • Most cases were PLA2R (phospholipase A2 receptor) negative, indicating a different cause.
  • Cases of MN linked to Neural epidermal growth factor-like protein 1 (NELL-1) have been identified.
  • NELL-1 has been associated with MN caused by traditional medicines containing high mercury levels.

Understanding Membranous Nephropathy

  • Membranous Nephropathy (MN) is a nephrotic syndrome, characterized by excessive protein leakage into urine, eventually leading to kidney failure. Symptoms such as fatigue, edema, and proteinuria were found to have a history of regular fairness cream usage.

Impact of Mercury:

  • Mercury in fairness creams inhibits melanin formation, resulting in lighter skin. Consumers perceive higher mercury levels as more effective for skin whitening.
  • Mercury, a potent heavy metal found in these creams, penetrates the body through various channels, including sweat glands and hair follicles, causing systemic toxicity.
  • Chronic exposure to mercury can result in kidney damage, neurological disorders, and a myriad of other health complications.

Back2Basics: Minamata Convention on Mercury

  • The Minamata Convention on Mercury is devised to safeguard human health and the environment from the detrimental impacts of mercury and its derivatives.
  • Its name derives from the Japanese bay where, during the mid-20th century, industrial wastewater tainted with mercury inflicted severe health damage upon thousands of individuals, leading to what is now recognized as “Minamata disease.”
  • Signed in 2013 and enforced in 2017, it operates as a United Nations treaty under the purview of the United Nations Environment Programme (UNEP).
  • Countries ratifying the Convention are legally obliged under international law to implement these regulations.
  • 128 countries are signatories, with 119 of them having ratified it; India became a party by ratifying it in 2018.

Activities covered by the Convention:

  • The Convention encompasses all phases of the mercury life cycle, aiming to regulate and diminish mercury usage across various products, processes, and industries.
  • This encompasses regulations about:
    • Mercury mining involves bans on new mines and the gradual phase-out of existing ones.
    • Gradual reduction and elimination of mercury utilization in numerous products and procedures.
    • Control measures address emissions into the atmosphere and release into soil and water bodies.
    • Oversight of the informal artisanal and small-scale gold mining sector.
    • Management of interim mercury storage and its disposal once classified as waste, as well as remediation of mercury-contaminated sites and associated health issues.

 

PYQ:

[2010] Indiscriminate disposal of used fluorescent electric lamps causes mercury pollution in the environment. Why is mercury used in the manufacture of these lamps?

(a) A mercury coating on the inside of the lamp makes the light bright white

(b) When the lamp is switched on, the mercury in the lamp causes the emission of ultra-violet radiations

(c) When the lamp is switched on, it is the mercury which converts the ultra-violet energy into visible light

(d) None of the statement given above is correct about the use of mercury in the manufacture of fluorescent lamps

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Innovations in Biotechnology and Medical Sciences

95Mat5 Antibody: Revolutionizing Snakebite Treatment

Note4Students

From UPSC perspective, the following things are important :

Prelims level: 95Mat5 Antibody

Mains level: NA

Why in the news?

After multiple rounds of screening, researchers have identified an antibody, 95Mat5 that showed promising results in making a potent antidote against various snake venoms.

What is 95Mat5?

  • 95Mat5 is a universal antivenom developed to neutralize the toxins present in snake venoms.
  • Development Process:
  1. The scientists first synthesized variants of a toxin called long-chain 3FTxs (3FTx-L), which are found in the venoms of various snakes, including cobras, kraits, mambas, and monocled cobras.
  2. They then screened billions of human antibodies expressed on the surface of yeast cells to find antibodies that bound best to the synthesized toxins.
  3. After multiple rounds of screening, they identified a shortlist of antibodies that broadly reacted with most of the 3FTx variants used in the study.
  4. The selected antibodies were further tested in vitro in human cells to determine which ones could best neutralize the toxins.

Mechanism of Action

  • 95Mat5 specifically targets α-neurotoxins, which are a specific class of 3FTxs that prevent nerve and muscle cells from responding to acetylcholine, a neurotransmitter involved in carrying messages from neurons to muscles.
  • By binding to the toxins, 95Mat5 prevents toxins from interacting with the receptors in human nerve and muscle cells, thereby blocking their ability to induce paralysis and other deadly effects.
  • In animal experiments, 95Mat5 demonstrated efficacy in neutralizing the toxins present in the venoms of various snake species, protecting the animals from death.

Global Impact of Snakebites

  • Venomous snakebites claim over 100,000 lives annually, with around 400,000 individuals suffering permanent disability.
  • Low and middle-income countries, especially India and Africa, bear the brunt of this burden.
    • India alone witnessing an average of 58,000 deaths each year.
  • In 2017, the World Health Organisation (WHO) declared snakebite envenoming as a highest priority Neglected Tropical Disease, shedding light on a long-hidden health crisis.

 

PYQ:

[2020] With reference to carbon nanotubes, consider the following statements:

  1. They can be used as carriers of drugs and antigens in the human body.
  2. They can be made into artificial blood capillaries for an injured part of human body.
  3. They can be used in biochemical sensors.
  4. Carbon nanotubes are biodegradable.

Which of the statements given above are correct?

(a) 1 and 2 only

(b) 2, 3 and 4 only

(c) 1, 3 and 4 only

(d) 1, 2, 3 and 4

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Innovations in Biotechnology and Medical Sciences

Plasma Therapy to Treat Rodenticide Poisoning

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Plasma Therapy; Plasmapheresis, Components of Human Blood;

Mains level: NA

Why in the news?

  • A significant health concern in Tamil Nadu is found through ingestion of Rat poison containing Yellow Phosphorus, leading to liver toxicity.
    • Since December 2017, the team at CMC Vellore introduced Plasma Exchange, (a cost-effective treatment) for acute liver failure caused by rat poison ingestion.

What is Plasma Therapy (Plasmapheresis)?

  • Plasma exchange, also known as plasmapheresis, is a medical procedure used to treat various conditions by removing and replacing plasma from the blood.
  • During Plasma Exchange, the patient’s blood is circulated through a machine that separates plasma from other blood components, such as red and white blood cells and platelets.

Working procedure:

  • The plasma, which may contain harmful substances or antibodies, is discarded.
  • The remaining blood components are mixed with replacement plasma or a plasma substitute and returned to the patient’s bloodstream.

Usage of Plasmapheresis:

  • In Autoimmune diseases: Conditions such as Guillain-Barre syndrome, myasthenia gravis, systemic lupus erythematosus, and certain forms of vasculitis.
  • In Neurological disorders: Conditions such as multiple sclerosis, chronic inflammatory demyelinating polyneuropathy, and certain types of encephalitis.
  • In Toxicological emergencies: Poisoning or overdose with substances such as drugs, chemicals, or toxins that can be removed from the bloodstream through plasma exchange.

Benefits observed in TN’s Case

  • The treatment significantly improved survival rates, with 63.9% of patients treated in 2022-2023 successfully discharged.
  • Retrospective studies at CMC Vellore demonstrated promising outcomes, with survival rates of 75% among children and 80.2% among adults treated with plasma exchange.

What is Plasma in Human Blood?

  • Human blood plasma is the liquid component of blood, constituting about 55% of its total volume.
  • It is a pale yellowish fluid that carries various substances throughout the body, including nutrients, hormones, electrolytes, antibodies, and waste products.
  • Plasma plays a crucial role in maintaining homeostasis and transporting essential components to tissues and organs.

Composition:

  • Water: Approximately 90% of plasma consists of water, making it the primary solvent for carrying dissolved substances.
  • Proteins: Plasma contains a variety of proteins, including albumin, globulins, and fibrinogen. These proteins perform functions such as maintaining osmotic pressure, transporting lipids and hormones, and aiding in blood clotting.
  • Electrolytes: Plasma contains ions such as sodium, potassium, chloride, calcium, and bicarbonate, which help regulate fluid balance, pH, and nerve function.
  • Nutrients: Glucose, amino acids, lipids, and vitamins are transported in plasma and provide energy and building blocks for cells.
  • Waste Products: Metabolic waste products, such as urea, creatinine, and bilirubin, are transported in plasma to be eliminated from the body.
  • Hormones: Hormones produced by endocrine glands are carried in plasma to target tissues, where they regulate various physiological processes.
  • Gases: Oxygen and carbon dioxide are transported in plasma, primarily bound to hemoglobin in red blood cells.

Functions:

  • Plasma carries nutrients, gases, hormones, and waste products to and from cells throughout the body.
  • Plasma helps regulate fluid balance, electrolyte concentrations, pH, and temperature.
  • Antibodies and immune cells in plasma help defend against pathogens and foreign substances, contributing to the body’s immune response.
  • Plasma proteins such as fibrinogen play a crucial role in blood clotting, helping to stop bleeding and repair damaged blood vessels.
  • Plasma buffers changes in pH by absorbing or releasing hydrogen ions, helping maintain the body’s acid-base balance.

 

PYQ:

[2011] A married couple adopted a male child. A few years later, twin boys were born to them. The blood group of the couple is AB positive and 0 negative. The blood group of the three sons is A positive, B positive, and O positive. The blood group of the adopted son is-

(a) O positive

(b) A positive

(c) B positive

(d) Cannot be determined based on the given data

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Innovations in Biotechnology and Medical Sciences

Geroscience: the Science related to Ageing

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Geroscience, DNA Methylation

Mains level: NA

Why in the news?

  • Dr. Daniel Belsky from Columbia University introduced the concept of “Geroscience” and develops a blood test, termed “gerozyme,” to measure aging pace by studying DNA methylation.
  • Various research groups explore drugs like Metformin and Rapamycin to target aging and enhance immunity in the elderly.

What is Geroscience?

  • Geroscience refers to the interdisciplinary field focused on understanding the biological mechanisms of ageing and age-related diseases.
  • It involves studying various factors, including DNA methylation, enzyme activity (such as the gerozyme), socio-economic influences, and lifestyle interventions like nutrition, exercise, and music therapy.
  • It aims to develop strategies, such as drug interventions targeting specific ageing-related processes, to promote healthy ageing and combat age-related conditions like dementia.

What is DNA Methylation?

  • DNA Methylation is a process in which methyl groups (CH3) are added to the DNA molecule.
  • This modification typically occurs at cytosine bases within the DNA sequence, often in the context of CpG dinucleotides (where cytosine is followed by guanine).
  • DNA methylation plays a crucial role in regulating gene expression and maintaining genome stability.
  • It can affect various cellular processes, including embryonic development, X-chromosome inactivation, genomic imprinting, and silencing of repetitive DNA elements.
  • Aberrant DNA methylation patterns have been implicated in various diseases, including cancer and neurological disorders.

Drug Interventions in Geroscience

  • Metformin and TORC1 inhibitors show promise in targeting aging and improving immune response in seniors.
  • Research proposes rapamycin’s potential in extending longevity and combating age-related diseases.

Impact of Socio-Economic Factors in Ageing

  • Dr. Belsky’s research reveals the influence of socioeconomic status on DNA methylation levels, highlighting the role of disadvantage in ageing.
  • Columbia Aging Centre emphasizes the role of a balanced diet in supporting brain health and reducing inflammation.
  • Healthline.com advocates for proteins, healthy fats, and antioxidant-rich foods to promote healthy ageing, crucial for India’s ageing population.

PYQ:

[2011] At present, scientists can determine the arrangement or relative positions of genes or DNA sequences on a chromosome. How does this knowledge benefit us?

  1. It is possible to know the pedigree of livestock.
  2. It is possible to understand the causes of all human diseases.
  3. It is possible to develop disease-resistant animal breeds.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 only

(c) 1 and 3 only

(d) 1, 2 and 3

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Innovations in Biotechnology and Medical Sciences

Crafted in Indian labs, NexCAR19 takes India to next level in Cancer Care

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Science and Technology; Biotechnology; NexCAR19;

Mains level: Process and Significance of CAR T thearpy;

Why in the News? 

  • President Droupadi Murmu launched India’s first indigenously-developed CAR T-cell therapy, hailing it as a major breakthrough against cancer.
  • This therapy was developed by the Indian Institute of Technology (IIT) Bombay and the Tata Memorial Centre, and it is known as ‘NexCAR19 CAR T-cell therapy’.

BACK2BASICS:

What is CAR T cell thearpy? 

CAR T-cell therapy is a type of immunotherapy that involves modifying a patient’s T cells, a type of white blood cell that plays a crucial role in the immune system, to recognize and attack cancer cells. This therapy is designed to target specific proteins found on the surface of cancer cells, such as CD19, which is commonly found on B cells.

How are CAR-T cells made?

Significance of CAR T Thearpy:

  • Promising results:  This therapy has shown promising results in treating some types of blood cancers, including certain kinds of lymphoma, pediatric leukemia, and adult leukemia.  It has shown with approximately 70% of patients responding to the treatment.
  • Less time for treatment: CAR T-cell therapies are generally a single infusion with less than 2 weeks of inpatient care, while stem cell transplants and chemotherapy treatment regimens can take months to complete

Limitiations of CAR-T Therapy:

  • Risks of CAR-T Therapy: The efficacy of CAR-T therapy varies from person to person, and it is too early to declare it a complete cure. While it has shown remarkable progress in challenging cases, its effectiveness is not universal.
  • High Cost Therapy: NexCAR19 is priced at a fraction of its US counterpart, it remains relatively high for many Indians, ranging from ₹40 to 45 lakh.
  • It’s Side Effects includes:
    • Cytokine Release Syndrome (CRS): CRS is the most common side effect of CAR-T therapy, triggering an ‘Inflammatory Response’ that leads to immune system hyperactivity.
    • Neurotoxicity: Although not observed in early-stage clinical trials, neurotoxicity is a common side effect of CAR-T therapy that can manifest as confusion, seizures, or difficulty speaking or walking.
    • Infections and Blood Cell Counts: Patients undergoing CAR-T therapy may experience infections and low blood cell counts as anticipated side effects.

Conclusion: India’s is moving towards heralding a breakthrough in Cancer Care Therapy. Despite cost challenges, Government efforts are aimed to enhance accessibility and better outputs in Healthcare Sector.

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Innovations in Biotechnology and Medical Sciences

Microbial Formulations for Enhanced Agricultural Productivity

Note4Students

From UPSC perspective, the following things are important :

Prelims level: Bactolime, Bactogypsum, and Trichogypsum; Soil Microbes

Mains level: NA

Why in the news?

The Indian Institute of Spices Research (IISR), located in Kozhikode, has introduced and validated three new microbial formulations (Bactolime, Bactogypsum, and Trichogypsum) aimed at improving agricultural productivity.

IISR Microbial Formulations

  • It leverages granular lime and gypsum to address soil pH issues while simultaneously delivering beneficial microorganisms.
  • These are developed using IISR’s proprietary patent-applied technology.
  • The formulations are:
  1. Bactolime:
  • Bactolime, the flagship product, combines beneficial bacteria, specifically plant growth-promoting Rhizobacteria, with liming material in a single formulation.
  • This integration ensures not only the correction of soil acidity but also the provision of essential nutrients to plants.
  1. Bactogypsum and Trichogypsum:
  • The other two formulations, Bactogypsum and Trichogypsum, utilize gypsum as a base material to buffer soil pH to a near-neutral level.
  • By creating an optimal environment for beneficial microbes, these formulations improve soil structure, enhance the availability of secondary nutrients, and boost overall microbial activity.

Back2Basics: Soil Microbes

Soil microbes refer to microorganisms that inhabit the soil environment and play vital roles in soil health, nutrient cycling, and plant growth. These microorganisms are diverse and include bacteria, fungi, archaea, protozoa, and algae.