A facultative anaerobic organism is an organism, usually a bacterium, that makes ATP by aerobic respiration if oxygen is present but is also capable of switching to fermentation. In contrast, obligate anaerobes die in presence of oxygen. This article or section does not adequately cite its references or sources. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Adenosine 5-triphosphate (ATP) is a multifunctional nucleotide that is most important as a molecular currency of intracellular energy transfer. ... This article or section should be merged with aerobic metabolism. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... Fermentation in progress Fermentation is a process of energy production in a cell in an anaerobic environment (with no oxygen present). ... An anaerobic organism or anaerobe is any organism that does not require oxygen. ...

Some examples of Facultative anaerobic bacteria are the Staphylococci (Gram positive), Corynebacterium (Gram positive), and Listeria (Gram positive). Organisms in the Kingdom Fungi can also be facultative anaerobic, such as yeasts. Species S. aureus Staphylococcus (in Greek staphyle means bunch of grapes and coccos means granule) is a genus of gram-positive bacteria. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to Gram-negative bacteria, which are not affected by the stain. ... Species See text. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to Gram-negative bacteria, which are not affected by the stain. ... Species Listeria monocytogenes Listeria ivanovii Listeria innocua Listeria welshimeri Listeria seegligeri Listeria grayi Listeria innocua Listeria is a bacterial genus containing six species. ... Ernst Haeckels presentation of a three-kingdom system (Plantae, Protista, Animalia) in his 1866 Generelle Morphologie der Organismen). ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... Saccharomyces cerevisiae is a yeast used in both baking and brewing. ...

Factors influencing the switch are the concentrations of oxygen and fermentable material in the environment. In brewer's yeast, the Pasteur shift is the observed cessation of oxygen consumption when fermentable sugar is supplied. In a growing culture, the energy "economics" disfavors respiration due to the "overhead cost" of producing the apparatus, as long as sufficient fermentable substrate is available, even though the energy output per mole of fermented material is far less than from respiration's complete oxidation of the same substrate. Brewers yeast (also known as brewers yeast or brewing yeast) can mean any live yeast used in brewing. ...

See also

• Aerobic respiration
• Anaerobic respiration

This article or section should be merged with aerobic metabolism. ... Anaerobic respiration refers to the oxidation of molecules in the absence of oxygen to produce energy. ...

External links

• Facultative Anaerobic Bacteria
• Obligate Anaerobic Bacteria
• Anaerobic Bacteria and Anaerobic Bacteria in the decomposition (stabilization) of organic matter.