Monnet C, Aymes F, Corrieu G
Laboratoire de Génie et Microbiologie des Procédés Alimentaires, Institut National de la Recherche Agronomique, 78850 Thiverval-Grignon, France.
Appl Environ Microbiol. 2000 Dec;66(12):5518-20. doi: 10.1128/AEM.66.12.5518-5520.2000.
Lactococcus lactis subsp. lactis biovar diacetylactis strains are utilized in several industrial processes for producing the flavoring compound diacetyl or its precursor alpha-acetolactate. Using random mutagenesis with nitrosoguanidine, we selected mutants that were deficient in alpha-acetolactate decarboxylase and had low lactate dehydrogenase activity. The mutants produced large amounts of alpha-acetolactate in anaerobic milk cultures but not in aerobic cultures, except when the medium was supplemented with catalase, yeast extract, or hemoglobin.
乳酸乳球菌乳酸亚种双乙酰变种菌株被用于多个工业生产过程,以生产调味化合物双乙酰或其前体α-乙酰乳酸。利用亚硝基胍进行随机诱变,我们筛选出了α-乙酰乳酸脱羧酶缺陷且乳酸脱氢酶活性较低的突变体。这些突变体在厌氧的牛奶培养物中会产生大量α-乙酰乳酸,但在需氧培养物中则不会,除非培养基中添加了过氧化氢酶、酵母提取物或血红蛋白。