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Brettanomyces

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==''Brettanomyces'' Metabolism==
Like ''Saccharomyces'', ''Brettanomyces'' is [https://en.wikipedia.org/wiki/Crabtree_effect Crabtree] positive (produces alcohol in the presence of oxygen and high sugar concentration), and is [https://en.wikipedia.org/wiki/Petite_mutation petite] positive (unable to grow without carbon sources, and forms small colonies when able to grow on growth media) <ref name="smith_divol_2016"></ref>. Perhaps the most differentiating characteristic of ''Brettanomyces'' is its preference to ferment glucose in the presence of oxygen to produce ethanol and acetic acid, which is the opposite preference in [[Saccharomyces]] where the presence of oxygen inhibits fermentation (dubbed the "[https://en.wikipedia.org/wiki/Pasteur_effect Pasteur effect]"). Also opposite of most yeasts including ''Saccharomyces'', in a completely anaerobic environment ''Brettanomyces'' ceases alcoholic fermentation for about 7-8 hours before adapting to the anaerobic conditions <ref name="Agnolucci_2017" />. This was initially dubbed the "negative Pasteur effect" by Custers, and later the "Custers effect" by W. A. Scheffers <ref name="yakobson_introduction"></ref><ref>[http://link.springer.com/article/10.1007/BF02157944 On the inhibition of alcoholic fermentation in Brettanomyces yeasts under anaerobic conditions. W. A. Scheffers. 1961.]</ref>. Despite the Custers effect in ''Brettanomyces'', this genus is not classified as an "oxidative yeast" but rather as a "fermentative yeast" since oxidative yeasts produce little to no ethanol in the presence of glucose, and grow only on the surface of a liquid rather than within a liquid <ref>[https://books.google.com/books?id=XlHuCAAAQBAJ&pg=PA436&lpg=PA436&dq=oxidative+yeast&source=bl&ots=poULkx-VUd&sig=eqRoMnh8vIfC0NvBCqvbl6ghrSA&hl=en&sa=X&ved=0ahUKEwiGhZOXmdPXAhWHg1QKHdf5A6s4FBDoAQgnMAA#v=onepage&q=oxidative%20yeast&f=false Wofl, Laus. "Nonconventional Yeasts in Biotechnology: A Handbook." Springer Science & Business Media, Dec 6, 2012. Pg 436.]</ref><ref>[http://www.wyeastlab.com/wild-beer-brewing "Wild Beer Brewing" Wyeast website. Retrieved 11/22/2017.]</ref><ref>[http://laboratoryresearch.blogspot.com/2008/07/yeasts-and-yeastlike-fungi.html?m=1 "YEASTS AND YEASTLIKE FUNGI" Do You Know? blog. 2008. Retrieved 11/22/2017.]</ref>.
===Carbohydrate Metabolism and Fermentation Temperature===

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