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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>. A notable exception to this is the species ''B. naardenensis'', which only produces ethanol when oxygen is limited <ref name="Tiukova_2019" />.