Comparative genomic analysis was performed on eight species of lactic acid bacteria (LAB)-Lactococcus (L.) lactis, Lactobacillus (Lb.) plantarum, Lb. casei, Lb. brevis, Leuconostoc (Leu.) mesenteroides, Lb. fermentum, Lb. buchneri, and Lb. curvatus-to assess their glutamic acid production pathways. Glutamic acid is important for umami taste in foods. The only genes for glutamic acid production identified in the eight LAB were for conversion from glutamine in L. lactis and Leu. mesenteroides, and from glucose via citrate in L. lactis. Thus, L. lactis was considered to be potentially the best of the species for glutamic acid production. By biochemical analyses, L. lactis HY7803 was selected for glutamic acid production from among 17 L. lactis strains. Strain HY7803 produced 83.16 pmol/μl glutamic acid from glucose, and exogenous supplementation of citrate increased this to 108.42 pmol/μl. Including glutamic acid, strain HY7803 produced more of 10 free amino acids than L. lactis reference strains IL1403 and ATCC 7962 in the presence of exogenous citrate. The differences in the amino acid profiles of the strains were illuminated by principal component analysis. Our results indicate that L. lactis HY7803 may be a good starter strain for glutamic acid production.

中文翻译：

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基于比较基因组分析选择乳酸乳球菌 HY7803 用于生产谷氨酸。

对八种乳酸菌 (LAB) -乳酸乳球菌 (L.) lactis、植物乳杆菌 (Lb.)、Lb.进行了比较基因组分析。casei, Lb. brevis, Leuconostoc (Leu.) mesenteroides, Lb. 发酵液，Lb。布氏杆菌和Lb。curvatus - 评估其谷氨酸生产途径。谷氨酸对食物的鲜味很重要。在八个 LAB 中鉴定的唯一谷氨酸生产基因是从乳酸乳球菌和Leu 中的谷氨酰胺转化而来。mesenteroides，以及通过柠檬酸盐在L. lactis中提取葡萄糖。因此，L. lactis被认为可能是谷氨酸生产的最佳物种。通过生化分析，L. lactis从 17 种乳酸乳球菌菌株中选择 HY7803 用于生产谷氨酸。菌株 HY7803 从葡萄糖中产生 83.16 pmol/μl 谷氨酸，柠檬酸盐的外源补充将其增加到 108.42 pmol/μl。包括谷氨酸在内，在存在外源柠檬酸盐的情况下，菌株 HY7803 比乳酸乳球菌参考菌株 IL1403 和 ATCC 7962产生多 10 个游离氨基酸。通过主成分分析阐明了菌株氨基酸谱的差异。我们的结果表明，L. lactis HY7803 可能是一种良好的谷氨酸生产起始菌株。