Prokaryotes Overview

Study Notes

Evolved before the formation of a nucleus.
Typically small and simple in structure, facilitating easy transport of dissolved substances.
Feature pili (singular: pilus) for movement and adherence to surfaces.
Contain mesosomes, which are involved in aerobic respiration and cell wall formation.
Possess a glycocalyx (capsule or slime layer) that helps some bacteria evade phagocytosis by white blood cells.
Have fimbriae that enable attachment to host cells or substrates.
Can form endospores, allowing them to create dormant, highly resistant cells.
Lack a cytoskeleton.

Food Production:
- Bacteria like Lactobacillus and various yeasts and molds have a longstanding role in the fermentation of foods such as cheese, pickles, soy sauce, vinegar, wine, beer, and yogurt.
Pollution Clean-Up:
- Bioremediation utilizes microorganisms, fungi, and plants to detoxify contaminated environments, including the use of bacteria that digest hydrocarbons in oil spills.
Biomining:
- Prokaryotes are leveraged to extract minerals from ores, such as the bacterium Thiobacillus ferooxidans, which enhances copper recovery from mining waste while reducing costs.
Waste Disposal and Biogas Production:
- Bacteria decompose sewage waste through aerobic and anaerobic processes, converting organic matter into harmless sludge, and generating methane gas as an energy source for electricity, heating, or vehicle fuel.
Agricultural Uses:
- Prokaryotes play vital roles in biogeochemical cycles (like nitrogen, carbon, and phosphorus), facilitating nutrient movement through ecosystems.
Pest Control:
- Bacillus thuringiensis, a Gram-positive bacteria, produces a toxin (Bt toxin) that is effective against specific pests like mosquitoes and caterpillars, without harming humans or beneficial insects.