Ganesan Balasubramanian, Weimer Bart C
Western Dairy Center, Center for Microbe Detection and Physiology, Center for Integrated BioSystems, and Department of Nutrition and Food Sciences, Utah State University, Logan, Utah 84322-8700, USA.
Appl Environ Microbiol. 2004 Jan;70(1):638-41. doi: 10.1128/AEM.70.1.638-641.2004.
The objective of this study was to determine the role of a lactococcal branched-chain amino acid aminotransferase gene, ilvE, in the production of branched-chain fatty acids. Lactococcus lactis subsp. lactis LM0230 and an ilvE deletion mutant, JLS450, produced branched-chain fatty acids from amino and alpha-keto acids at levels above alpha-keto acid spontaneous degradation and the fatty acids' flavor thresholds. The deletion mutant produced the same amounts of branched-chain fatty acids from precursor amino acids as did the parent. This was not the case, however, for the production of branched-chain fatty acids from the corresponding precursor alpha-keto acids. The deletion mutant produced a set of fatty acids different from that produced by the parent. We concluded from these observations that ilvE plays a role in the specific type of fatty acids produced but has little influence on the total amount of fatty acids produced by lactococci.
本研究的目的是确定乳酸乳球菌支链氨基酸转氨酶基因ilvE在支链脂肪酸产生过程中的作用。乳酸乳球菌乳酸亚种LM0230和ilvE缺失突变体JLS450从氨基酸和α-酮酸产生支链脂肪酸的水平高于α-酮酸的自发降解水平以及脂肪酸的风味阈值。缺失突变体从前体氨基酸产生的支链脂肪酸量与亲本相同。然而，从相应的前体α-酮酸产生支链脂肪酸的情况并非如此。缺失突变体产生的一组脂肪酸与亲本产生的不同。我们从这些观察结果得出结论，ilvE在乳球菌产生的特定类型脂肪酸中起作用，但对乳球菌产生的脂肪酸总量影响很小。
