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====''Oenococcus oeni''====
''Oenococcus oeni''(also know as ''Leuconostoc oeni'') is a Genus of Gram-positive LAB, ellipsoidal to spherical in shape that is primarily used in Malolactic Fermentation. ''Oenococcus oeni'' is a facultative anaerobe. It is able to use oxygen for cellular respiration but can also gain energy through fermentation. It characteristically grows well in the environments of wine, being able to survive in acidic conditions below pH 3.0 and tolerant of ethanol levels above 10%. Optimal growth occurs on sugar and protein rich media. Cells tend to grow in chains or pairs. ''O. Oeni'' is heterofermentative and generally produces CO2, Ethanol, Acetate, and Diacetyl.<ref name="MicrobeWikiOO">[https://microbewiki.kenyon.edu/index.php/Oenococcus_oeni. Microbe Wiki's Info on O. Oeni .]</ref>
''O. oeni'' ferments sugars using both the hexose-monophosphate and phosphoketolase pathways using the enzymes Glucose-6-phosphate and xylulose-5-phosphoketolase to from D(-)-lactic acid, CO2 and ethanol in equal amounts when metabolising D-glucose. O.oeni can convert pentose phosphate to acetic acid in an oxygen dependant reaction which requires NADP. It cannot metabolize polysaccharides and alcohols.
''O. oeni'' can decarboxylate L-malate to L(+)-lactate, but cannot use it as a sole source of carbon. It requires the amino acids Glutamic acid, valine, guanine, adenine, xanthine, uracil, riboflavin, folic acid, nicotinic acid, thiamine, biotine and pantothenic acid. There is some variation of amino acid requirement between strains.<ref name="UCDavisOO">[http://wineserver.ucdavis.edu/industry/enology/winemicro/winebacteria/oenococcus_oeni.html. UC Davis General Info on O. Oeni .]</ref>
Althought ''O. Oeni'' has primarily been used for Malolactic Fermentation, trials with the White Labs culture(only one reported on so far) has show lactic acid production without the presence of malic acid. <ref name="post">[https://www.facebook.com/groups/MilkTheFunk/permalink/1121887807839432/. James Site's FB post.]</ref> James Sites reported souring within a week at 70F.