Tang Taya, Leisner Jørgen J
Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870, Frederiksberg C, Denmark.
Probiotics Antimicrob Proteins. 2024 Sep 21. doi: 10.1007/s12602-024-10361-w.
It has not been extensively examined if the ecological role of lactic acid bacterial bacteriocins may affect their distribution in different habitats and thereby impact screenings for novel variants. Further, the functionality of such variants requires additional investigation. This study investigated the distribution of bacteriocin biosynthetic gene clusters (BGCs) and bacteriocinogenic activity of Lactococcus cremoris and Lactococcus lactis from a range of different environments. Whole genome sequencing and phylogenetic analysis of fifty L. cremoris and L. lactis strains showed distinct species clustering without significant genome size differences between species or sources. Genomic screening with AntiSMASH and BAGEL4 identified several BGCs, with variation based on species but not on habitat. Deferred inhibition assays revealed pronounced activity only in strains possessing nisin or lactococcin B BGCs and not in strains with other BGCs. Several hitherto undescribed types of lactococcin BGCs appeared to be incomplete regarding genes encoding secretion and immunity. In conclusion, this study indicates that habitats did not appear to affect distribution of BGCs. Further, the antagonistic functionality of several BGCs was unclear indicating that improving applications of lactococcal bacteriocins may depend as much or more on research on increasing efficacy of well-known bacteriocins than searching for novel variants.
乳酸菌细菌素的生态作用是否会影响其在不同生境中的分布，进而影响新型变体的筛选，目前尚未得到广泛研究。此外，此类变体的功能还需要进一步研究。本研究调查了来自一系列不同环境的乳酸乳球菌和乳酸乳杆菌中细菌素生物合成基因簇（BGCs）的分布及产细菌素活性。对50株乳酸乳球菌和乳酸乳杆菌菌株进行全基因组测序和系统发育分析，结果显示不同物种聚类明显，物种或来源之间的基因组大小无显著差异。使用AntiSMASH和BAGEL4进行基因组筛选，鉴定出了几个BGCs，其变异基于物种而非生境。延迟抑制试验表明，只有携带乳链菌肽或乳酸乳球菌素B BGCs的菌株具有明显活性，而携带其他BGCs的菌株则没有。几种迄今未描述的乳酸乳球菌素BGCs在编码分泌和免疫的基因方面似乎不完整。总之，本研究表明生境似乎并未影响BGCs的分布。此外，几种BGCs的拮抗功能尚不清楚，这表明提高乳酸乳球菌细菌素的应用可能在很大程度上或更多地依赖于提高已知细菌素效力的研究，而不是寻找新型变体。
