Microbial metabolism

• What do microorganisms need energy for?

  To grow, move, reproduce, and defend
• What is required to produce energy in microorganisms?

  Nutrients and enzymes
• How do most microbes gain energy if oxygen is available?

  Through respiration
• What do anaerobes use to gain energy in the absence of oxygen?

  Fermentation
• What is fermentation?

  Conversion of carbohydrates to acids and alcohols
• Give an example of fermentation by yeast.

  Conversion of maltose to alcohol
• What do lactobacilli convert lactose into?

  Lactic acid
• What happens to pyruvate in aerobic respiration?

  It is oxidized to acetyl CoA
• What are the by-products of aerobic respiration?

  ATP and CO2
• What is the theoretical yield of ATP per glucose molecule in aerobic respiration?

  38 ATP molecules
• What occurs to pyruvate in anaerobic respiration?

  It is reduced to lactate or alcohol
• What is the theoretical yield of ATP per glucose molecule in anaerobic respiration?

  2 ATP molecules
• What are obligate aerobes?

  Organisms that cannot survive without oxygen
• Give an example of an obligate aerobe.

  Cryptococcus neoformans
• What are facultative aerobes?

  Primarily anaerobic but can respire using oxygen
• Give an example of a facultative aerobe.

  Ralstonia metallidurans
• What are obligate anaerobes?

  Vegetative cells that cannot grow in oxygen
• Give an example of an obligate anaerobe.

  Clostridium perfringens
• What are facultative anaerobes?

  Primarily aerobic but can respire anaerobically
• Give an example of a facultative anaerobe.

  Staphylococcus aureus
• What is the main source of carbon for most cells?

  The atmosphere and organic compounds
• What are autotrophs?

  Organisms that produce their own food using CO2
• What are heterotrophs?

  Organisms that eat plants or animals for nutrients
• What do photoautotrophic organisms use for energy?

  Light to synthesize organic molecules
• Give an example of a photoautotrophic organism.

  Rhodospirillum rubrum
• What do photoheterotrophic microbes use for energy?

  Light and organic compounds
• Give an example of a photoheterotrophic microbe.

  Rhodobacter sphaeroides
• What do chemoautotrophic organisms use for food?

  Inorganic energy sources and CO2
• Give an example of a chemoautotrophic organism.

  Thiomicrospira denitrificans
• What do chemoheterotrophic organisms rely on for nutrients?

  Other organisms for carbon sources
• Give an example of a chemoheterotrophic organism.

  Lactobacillus acidophilus
• What is the role of phosphorus in microorganisms?

  Nucleic acids and phospholipids
• What is the role of sulfur in microorganisms?

  Amino acids, vitamins, and enzymes
• What is the role of potassium in microorganisms?

  Enzymes for protein synthesis
• What is the role of calcium in microorganisms?

  Stabilizes cell walls
• What are trace elements in microorganisms?

  Essential for enzyme production
• What is the role of cobalt in microorganisms?

  For enzyme production
• What is the role of selenium in microorganisms?

  Used for synthesis of amino acids
• What is the role of tungsten in microorganisms?

  Used for synthesis of amino acids
• What are siderophores?

  Iron chelators that bond iron