PDF(Pubmed)
Abstract：
Members of the Bacillus cereus group are spore-forming Gram-positive bacilli that are commonly associated with diarrheal or emetic food poisoning. They are widespread in nature and frequently present in both raw and processed food products. Here, we genetically characterized 24 B. cereus group isolates from foodstuffs. Whole-genome sequencing (WGS) revealed that most of the isolates were closely related to B. cereus sensu stricto (12 isolates), followed by B. pacificus (5 isolates), B. paranthracis (5 isolates), B. tropicus (1 isolate), and \"B. bingmayongensis\" (1 isolate). The most detected virulence genes were BAS_RS06430, followed by bacillibactin biosynthesis genes (dhbA, dhbB, dhbC, dhbE, and dhbF), genes encoding the three-component non-hemolytic enterotoxin (nheA, nheB, and nheC), a gene encoding an iron-regulated leucine-rich surface protein (ilsA), and a gene encoding a metalloprotease (inhA). Various biofilm-associated genes were found, with high prevalences of tasA and sipW genes (matrix protein-encoding genes); purA, purC, and purL genes (eDNA synthesis genes); lytR and ugd genes (matrix polysaccharide synthesis genes); and abrB, codY, nprR, plcR, sinR, and spo0A genes (biofilm transcription regulator genes). Genes related to fosfomycin and beta-lactam resistance were identified in most of the isolates. We therefore demonstrated that WGS analysis represents a useful tool for rapidly identifying and characterizing B. cereus group strains. Determining the genetic epidemiology, the presence of virulence and antimicrobial resistance genes, and the pathogenic potential of each strain is crucial for improving the risk assessment of foodborne B. cereus group strains.
摘要：
蜡状芽孢杆菌组的成员是形成孢子的革兰氏阳性杆菌，通常与腹泻或呕吐性食物中毒有关。它们在自然界中广泛存在，并且经常存在于原料和加工食品中。这里,我们对来自食品的24个蜡状芽孢杆菌组分离物进行了基因鉴定。全基因组测序（WGS）显示，大多数分离株与蜡样芽孢杆菌（12株）密切相关，其次是太平洋芽孢杆菌(5个分离株)，B.paranthracis(5个分离株)，B.热带（1个分离），和\"B.bingmayongensis\“(1个分离物)。检测最多的毒力基因是BAS_RS06430，其次是杆菌素生物合成基因(dhbA，dhbb,dhbc,dhbE,和dhbF)，编码三组分非溶血性肠毒素的基因(nheA，nheB,和nheC)，编码铁调节的富含亮氨酸的表面蛋白（ilsA）的基因，和编码金属蛋白酶(inhA)的基因。发现了各种与生物膜相关的基因，具有高的tasA和sipW基因（基质蛋白编码基因）；purA，purc,和purL基因(eDNA合成基因)；lytR和ugd基因(基质多糖合成基因)；和abrB，codY,nprR,plcR,sinR,和spo0A基因(生物膜转录调节基因)。在大多数分离物中鉴定了与磷霉素和β-内酰胺抗性相关的基因。因此，我们证明了WGS分析代表了快速鉴定和表征蜡状芽孢杆菌群菌株的有用工具。确定遗传流行病学，毒力和抗菌素抗性基因的存在，每个菌株的致病潜力对于提高食源性蜡样芽孢杆菌组菌株的风险评估至关重要。
