不利的环境条件,如酸胁迫,诱导细菌采用几种策略来克服这些应激源。这些策略包括形成生物膜和激活特定的分子途径,如一般应激反应(GSR)。使用IlluminaNextSeq500系统对大型Priestia菌株G18的基因组进行了测序,导致80个脚手架的从头组装。支架基因组包含5,367,956bp,GC含量为37.89%,并使用MiGA网络服务器与相关菌株进行了比较,与巨大P.MBRC15308和P.aryabhattaiB8W22高度相似,ANI评分为95.4%。系统发育和核糖体多位点序列分型(rMLST)分析,基于16SrRNA和核糖体蛋白编码等位基因,证实了巨大疟原虫物种内的密切关系。功能注释确定了5,484个蛋白质编码基因,72.31%被分为22个COG类别,强调在氨基酸运输中的作用,转录,碳水化合物代谢,和核糖体结构。对巨大假单胞菌G18的深入基因组分析揭示了与酸耐受性相关的几个关键基因。来自SigB调节子的ydaG基因的靶向失活,一般的应激反应基因,与野生型相比,酸性条件下的生长显着降低。qRT-PCR分析显示在酸性条件下ydaG表达增加,进一步支持其在酸应激反应中的作用。显微镜分析显示野生型和突变细胞之间没有形态学差异,表明ydaG不参与维持细胞形态,而是通过应激蛋白的产生促进酸耐受性。这项研究有助于了解土壤细菌耐酸的分子机制,巨大的P.,阐明在农业和工业中的潜在应用。
Adverse environmental conditions, such as acid stress, induce bacteria to employ several strategies to overcome these stressors. These strategies include forming biofilms and activating specific molecular pathways, such as the general stress response (GSR). The genome of Priestia megaterium strain G18 was sequenced using the Illumina NextSeq 500 system, resulting in a de novo assembly of 80 scaffolds. The scaffolded genome comprises 5,367,956 bp with a GC content of 37.89%, and was compared to related strains using the MiGA web server, revealing high similarity to P. megaterium NBRC 15308 and P. aryabhattai B8W22 with ANI scores of 95.4%. Phylogenetic and ribosomal multilocus sequence typing (rMLST) analyses, based on the 16S rRNA and ribosomal protein-encoding alleles, confirmed close relationships within the P. megaterium species. Functional annotation identified 5,484 protein-coding genes, with 72.31% classified into 22 COG categories, highlighting roles in amino acid transport, transcription, carbohydrate metabolism, and ribosomal structure. An in-depth genome analysis of P. megaterium G18 revealed several key genes associated with acid tolerance. Targeted inactivation of the ydaG gene from SigB regulon, a general stress response gene, significantly reduced growth under acidic conditions compared to the wild type. qRT-PCR analysis showed increased ydaG expression in acidic conditions, further supporting its role in acid stress response. Microscopic analysis revealed no morphological differences between wild-type and mutant cells, suggesting that ydaG is not involved in maintaining cellular morphology but in facilitating acid tolerance through stress protein production. This research contributes to understanding the molecular mechanisms underlying acid tolerance in soil bacteria, P. megaterium, shedding light on potential applications in agriculture and industry.