Extremophile
Context:
Scientists have discovered bacteria living inside microwave ovens.
About Bacteria:
- Definition: Bacteria are microscopic, single-celled organisms that exist in their millions, in every environment, both inside and outside other organisms. They are ubiquitous, mostly free-living organisms often consisting of one biological cell. Bacteria constitute a large domain of prokaryotic microorganisms.
- Cell Structure: Bacteria are classified into five groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.
- Bacterial cells are different from plant and animal cells. Bacteria are prokaryotes, which means they have no nucleus.
- A bacterial cell includes: a cell wall, cell membrane, cytoplasm, Ribosomes, Plasmids, Flagella (some species), Pili (some species).
- Bacterial Reproduction: Most bacteria reproduce by binary fission.
- In this process the bacterium, which is a single cell, divides into two identical daughter cells. When conditions are favourable such as the right temperature and nutrients are available, some bacteria like Escherichia coli can divide every 20 minutes.
- Some bacteria can form endospores, which are dormant structures that are extremely resistant to hostile physical and chemical conditions such as heat, UV radiation and disinfectants.
- Bacterial Habitats and Roles: Scientists have isolated microbes from a variety of extreme environments, including volcanic vents, permafrost, acid mines, deep-sea hydrothermal vents, and dark lakes buried kilometres beneath polar ice caps.
Extremophiles are organisms that thrive in environments that would be considered hostile to most life forms. They have evolved to tolerate extreme conditions, such as high temperatures, low temperatures, high salinity, high pressure, or extreme pH.
Importance of Bacteria:
- Ecosystem Function: Bacteria are crucial for nutrient cycling in ecosystems. They decompose organic matter, recycle nutrients, and contribute to soil fertility, which is essential for plant growth.
- Human Health: The human body hosts a vast number of bacteria, primarily in the gut, which aid in digestion, synthesise vitamins (like vitamin K), and support the immune system. These beneficial bacteria help maintain a balanced microbiome, which is vital for overall health.
- Biotechnology and Industry: Bacteria are utilised in various industrial processes, including the production of antibiotics, enzymes, and fermented foods like yogurt and cheese. They are also employed in bioremediation to clean up oil spills and treat sewage.
- Agriculture: Certain bacteria, such as nitrogen-fixing species, enhance soil fertility by converting atmospheric nitrogen into forms usable by plants. This symbiotic relationship supports agricultural productivity.
Harmful Effects of Bacteria:
- Pathogenic Bacteria: A small proportion of bacteria are pathogenic and can cause diseases in humans, animals, and plants.
- Notable examples include Streptococcus (causing strep throat), Escherichia coli (certain strains causing food poisoning), and Mycobacterium tuberculosis (causing tuberculosis).
- Antibiotic Resistance: The overuse of antibiotics has led to the emergence of antibiotic-resistant bacteria, making infections harder to treat and posing a significant public health challenge.
- Disruption of Microbiome: Factors such as antibiotic use, poor diet, and stress can disrupt the balance of beneficial bacteria in the gut, leading to dysbiosis.
Earth Microbiome Project (EMP) It is a large-scale, collaborative initiative aimed at characterising microbial life across the globe. Established in 2010, the EMP seeks to understand microbial diversity, distribution, and function through systematic sampling and analysis of various environments. Earth Biogenome Project (EBP) It is another ambitious initiative, but it focuses on sequencing and cataloguing the genomes of all known eukaryotic species on Earth. Launched in 2018, the EBP aims to provide a comprehensive genomic reference for biodiversity, which can aid in conservation efforts and enhance our understanding of biology.
