Kok J
Department of Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Haren, The Netherlands.
Antonie Van Leeuwenhoek. 1996 Oct;70(2-4):129-45. doi: 10.1007/BF00395930.
Relatively recently, a number of genes and operons have been identified in lactic acid bacteria that are inducible and respond to environmental factors. Some of these genes/operons had been isolated and analysed because of their importance in the fermentation industry and, consequently, their transcription was studied and found to be regulatable. Examples are the lactose operon, the operon for nisin production, and genes in the proteolytic pathway of Lactococcus lactis, as well as xylose metabolism in Lactobacillus pentosus. Some other operons were specifically targetted with the aim to compare their mode of regulation with known regulatory mechanisms in other well-studied bacteria. These studies, dealing with the biosynthesis of histidine, tryptophan, and of the branched chain amino acids in L. lactis, have given new insights in gene regulation and in the occurrence of auxotrophy in these bacteria. Also, nucleotide sequence analyses of a number of lactococcal bacteriophages was recently initiated to, among other things, specifically learn more about regulation of the phage life cycle. Yet another approach in the analysis of regulated genes is the 'random' selection of genetic elements that respond to environmental stimuli and the first of such sequences from lactic acid bacteria have been identified and characterized. The potential of these regulatory elements in fundamental research and practical (industrial) applications will be discussed.
相对较近的时候，在乳酸菌中发现了一些可诱导并对环境因素作出反应的基因和操纵子。其中一些基因/操纵子因其在发酵工业中的重要性而被分离和分析，因此，对它们的转录进行了研究并发现是可调控的。例如乳糖操纵子、乳链菌肽生产操纵子、乳酸乳球菌蛋白水解途径中的基因，以及戊糖乳杆菌中的木糖代谢。其他一些操纵子则是专门针对其进行研究，目的是将它们的调控模式与其他深入研究的细菌中已知的调控机制进行比较。这些关于乳酸乳球菌中组氨酸、色氨酸和支链氨基酸生物合成的研究，为这些细菌的基因调控和营养缺陷型的发生提供了新的见解。此外，最近还开始了对一些乳球菌噬菌体的核苷酸序列分析，以便特别更多地了解噬菌体生命周期的调控。分析受调控基因的另一种方法是“随机”选择对环境刺激作出反应的遗传元件，并且已经鉴定和表征了来自乳酸菌的首批此类序列。将讨论这些调控元件在基础研究和实际（工业）应用中的潜力。
