Aerobe

Examples of Aerobe in the following topics:

• Oxygen

  • An aerobic organism or aerobe is an organism that can survive and grow in an oxygenated environment.
  • Several varietis of aerobes exist .
  • Obligate aerobes require oxygen for aerobic cellular respiration.
  • Since normal microbial culturing occurs in atmospheric air, which is an aerobic environment, the culturing of anaerobes poses a problem.
  • Aerobically different bacteria behave differently when grown in liquid culture: 1) Obligate aerobic bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. 2) Obligate anaerobic bacteria gather at the bottom to avoid oxygen. 3) Facultative bacteria gather mostly at the top, since aerobic respiration is advantageous (ie, energetically favorable); but as lack of oxygen does not hurt them, they can be found all along the test tube. 4) Microaerophiles gather at the upper part of the test tube but not at the top.

• Acetyl CoA and the Citric Acid Cycle

  • The citric acid cycle is a key component of the metabolic pathway by which all aerobic organisms generate energy.
  • The citric acid cycle, shown in —also known as the tricarboxylic acid cycle (TCA cycle) or the Krebs cycle—is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate—derived from carbohydrates, fats, and proteins—into carbon dioxide.
  • The citric acid cycle is a key component of the metabolic pathway by which all aerobic organisms generate energy.
  • The citric acid cycle, or Krebs cycle, is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidization of acetate—derived from carbohydrates, fats, and proteins—into carbon dioxide.

• Aerobic Hydrocarbon Oxidation

  • Note the presence of oxygen, thus defining this as aerobic hydrocarbon oxidation.
  • Discuss the advantages of organisms that can undergo aerobic hydrocarbon oxidation

• Respiration and Proton Motive Force

  • Aerobic reactions require oxygen for ATP generation.
  • During aerobic conditions, the pyruvate enters the mitochondrion to be fully oxidized by the Krebs cycle.
  • Aerobic metabolism is up to 15 times more efficient than anaerobic metabolism, which yields two molecules ATP per one molecule glucose.
  • Both types of metabolism share the initial pathway of glycolysis, but aerobic metabolism continues with the Krebs cycle and oxidative phosphorylation.

• Morphologically Unusual Proteobacteria

  • They are twisted and aerobic, and are highly flexible, like a spring.
  • Prosthecates are generally chemoorganotrophic aerobes that can grow in nutrient-poor habitats, being able to survive at nutrient levels on the order of parts-per-million - for which reason they are often found in aquatic habitats.
  • Some prosthecates will grow in nutrient-poor soils as aerobic heterotrophs.

• The Degradation of Synthetic Chemicals in Soils and Water

  • Decomposition of the toxic substances can be performed both in the presence (aerobically) and absence (anaerobically) of oxygen.
  • The degradation is performed in the anaerobic, aerobic, and composting steps.
  • In the aerobic step, oxygen is added into the system and the organic matter is converted to carbon dioxide.

• Betaproteobacteria

  • The Betaproteobacteria consist of several groups of aerobic or facultative bacteria that are often highly versatile in their degradation capacities, but also contain chemolithotrophic genera (e.g., the ammonia-oxidising genus Nitrosomonas) and some phototrophs (members of the genera Rhodocyclus and Rubrivivax).
  • The Burkholderia (previously part of Pseudomonas) genus name refers to a group of virtually ubiquitous gram-negative, motile, obligately aerobic rod-shaped bacteria including both animal/human (see above) and plant pathogens as well as some environmentally important species.

• Fermentation Without Substrate-Level Phosphorylation

  • The antibiotic activity of Hops also inhibits aerobic metabolism in Yeast.
  • Pyruvic acid supplies energy to living cells through the citric acid cycle (also known as the Krebs cycle) when oxygen is present (aerobic respiration), and alternatively ferments to produce lactic acid when oxygen is lacking (fermentation).

• The Energetics of Chemolithotrophy

  • ., carbon dioxide fixation) or energy conservation via aerobic or anaerobic respiration.
  • The electron acceptor can be oxygen (in aerobic bacteria), but a variety of other electron acceptors, organic and inorganic, are also used by various species.

• Hydrogen Oxidation

  • While there are several mechanisms of anaerobic hydrogen oxidation, organisms can also use hydrogen as an energy source aerobically.
  • While there are several mechanisms of anaerobic hydrogen oxidation (e.g. sulfate reducing- and acetogenic bacteria), hydrogen can also be used as an energy source aerobically.
  • Discuss the process of hydrogen oxidation in organisms that use hydrogen aerobically