Microbial Nutrition Quiz

Study Notes

Bacteria require constant influx of substances for survival and metabolic functions.
Essential elements include carbon, hydrogen, oxygen, phosphorus, potassium, nitrogen, sulfur, calcium, iron, sodium, chloride, and magnesium.
Microbes obtain nutrients from diverse sources.

Nutrition involves acquiring chemical substances (nutrients) from the environment for cellular activities.

Essential nutrients are substances that must be provided, categorized into:
- Macronutrients: required in large quantities for cell structure and metabolism.
- Micronutrients (Trace Elements): required in smaller amounts, crucial for enzyme function and protein structure.

Organic Nutrients: Contain carbon and hydrogen; products of living organisms, such as carbohydrates, lipids, proteins, and nucleic acids.
Inorganic Nutrients: Atoms or simple molecules lacking carbon and hydrogen; found in earth's crust, water bodies, and atmosphere.

Carbon:
- Fundamental macronutrient, vital for cellular components.
- Backbone of organic molecules, also provides oxygen and hydrogen.
- Crucial for energy production and metabolic processes.
Nitrogen:
- Main reservoir is nitrogen gas (N2), constituting 79% of the atmosphere.
- Integral to proteins, DNA, RNA, and ATP.
- Some organisms utilize inorganic nitrogen forms (NO3-, NO2-, NH3); nitrogen fixation converts N2 to usable forms (NH3).
Oxygen:
- Major component of carbohydrates, lipids, and proteins.
- Important for structural and enzymatic functions.
- Constituent of inorganic salts and water; makes up 20% of the atmosphere.
- Essential for many organisms' metabolism.
Hydrogen:
- Major element in organic and some inorganic compounds.
- Functions include maintaining pH, forming hydrogen bonds, and providing free energy in redox reactions.
Phosphorus:
- Component of phospholipids, DNA, RNA, ATP, and proteins.
- Main inorganic source is phosphate (PO4-3) from phosphoric acid found in rocks and ocean minerals.
- Key for nucleic acids and energy transfer in ATP.
Sulfur:
- Found in nature as sulfate, sulfides, and hydrogen sulfide.
- Essential for amino acids and vitamins; stabilizes proteins through disulfide bonds.