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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 only grow as scum on the surface of a liquid rather than within the liquid <ref>[http://www.sciencedirect.com/science/article/pii/S0308814606002457 The production of ethylphenols in wine by yeasts of the genera Brettanomyces and Dekkera: A review. R.Suárez, J.A.Suárez-Lepe, A.Morata, F.Calderón. 2007.]</ref><ref>[https://search.proquest.com/docview/733013604?pq-origsite=gscholar Fermentation characteristics of Dekkera bruxellensis strains. Blomqvist, Johanna; Eberhard, Thomas; Schnürer, Johan; Passoth, Volkmar. 2010.]</ref><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>.
The Custers effect is abolished under anaerobic conditions when [https://en.wikipedia.org/wiki/Nitrate nitrate] is available. Under conditions where there is no oxygen, as long as nitrates are available, it has been shown that ''Brettanomyces'' can produce ethanol just as capably as ''S. cerevisiae'' <ref>[https://link.springer.com/article/10.1007%2Fs10295-012-1229-3 Utilization of nitrate abolishes the “Custers effect” in Dekkera bruxellensis and determines a different pattern of fermentation products. Silvia Galafassi, Claudia Capusoni, Md Moktaduzzaman, Concetta Compagno. 2013.]</ref><ref>[https://link.springer.com/article/10.1007/s10295-018-2118-1 Nitrate boosts anaerobic ethanol production in an acetate-dependent manner in the yeast Dekkera bruxellensis. Irina Charlot Peña-Moreno, Denise Castro Parente, Jackeline Maria da Silva, Allyson Andrade Mendonça, Lino Angel Valcarcel Rojas, Marcos Antonio de Morais Junior, Will de Barros Pita. 2018.]</ref>. Brewers who prefer the character of ''Brettanomyces'' in their beer can take advantage of this ability by limiting oxygen and providing a food source for ''Brettanomyces'' (aka beer or wort). See [[Brettanomyces#Nitrogen_Metabolism|Nitrogen Metabolism]] below.
===Carbohydrate Metabolism and Fermentation Temperature===