TI food & Nutrition, Kluyver Centre for Genomics of Industrial Fermentation, Po Box 557, 6700 AN, Wageningen, the Netherlands.
Microb Cell Fact. 2009 May 29;8:28. doi: 10.1186/1475-2859-8-28.
For some lactic acid bacteria higher biomass production as a result of aerobic respiration has been reported upon supplementation with heme and menaquinone. In this report, we have studied a large number of species among lactic acid bacteria for the existence of this trait.
Heme- (and menaquinone) stimulated aerobic growth was observed for several species and genera of lactic acid bacteria. These include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacilllus brevis, Lactobacillus paralimentarius, Streptococcus entericus and Lactococcus garviae. The increased biomass production without further acidification, which are respiration associated traits, are suitable for high-throughput screening as demonstrated by the screening of 8000 Lactococcus lactis insertion mutants. Respiration-negative insertion-mutants were found with noxA, bd-type cytochrome and menaquinol biosynthesis gene-disruptions. Phenotypic screening and in silico genome analysis suggest that respiration can be considered characteristic for certain species.
We propose that the cyd-genes were present in the common ancestor of lactic acid bacteria, and that multiple gene-loss events best explains the observed distribution of these genes among the species.
据报道，一些乳酸菌在补充血红素和甲萘醌后，由于有氧呼吸而产生更高的生物量。在本报告中，我们研究了乳酸菌中的大量物种，以研究这种特性的存在。
观察到几种乳酸菌的物种和属存在血红素（和甲萘醌）刺激的有氧生长。这些包括植物乳杆菌、鼠李糖乳杆菌、短乳杆菌、副干酪乳杆菌、肠球菌和乳球菌 garviae。这种不进一步酸化的生物量增加，与呼吸有关的特征，适合高通量筛选，如对 8000 个乳球菌 lactis 插入突变体的筛选所示。发现了无 noxA、bd 型细胞色素和甲萘醌醇生物合成基因缺失的呼吸阴性插入突变体。表型筛选和计算机基因组分析表明，呼吸可以被认为是某些物种的特征。
我们提出 cyd 基因存在于乳酸菌的共同祖先中，并且多个基因缺失事件最好地解释了这些基因在物种中的分布。
