Geier Renae R, Rehberger Thomas G, Smith Alexandra H
Arm and Hammer Animal and Food Production, Church & Dwight Co., Inc., Waukesha, WI, United States.
Front Microbiol. 2021 Jun 9;12:649953. doi: 10.3389/fmicb.2021.649953. eCollection 2021.
is an opportunistic pathogenic bacterium that infects both animals and humans. genomes encode a diverse array of toxins and virulence proteins, which continues to expand as more genomes are sequenced. In this study, the genomes of 44 strains isolated from intestinal sections of diseased cattle and from broiler chickens from diseased and healthy flocks were sequenced. These newly assembled genomes were compared to 141 publicly available genome assemblies, by aligning known toxin and virulence protein sequences in the assemblies using BLASTp. The genes for alpha toxin, collagenase, a sialidase (), and alpha-clostripain were present in at least 99% of assemblies analyzed. In contrast, beta toxin, epsilon toxin, iota toxin, and binary enterotoxin of toxinotypes B, C, D, and E were present in less than 5% of assemblies analyzed. Additional sequence variants of beta2 toxin were detected, some of which were missing the leader or signal peptide sequences and therefore likely not secreted. Some pore-forming toxins involved in intestinal diseases were host-associated, the gene was only found in avian isolates, while , , and were only present in canine and equine isolates. Alveolysin was positively associated with canine and equine strains and only present in a single monophyletic clade. Strains from ruminant were not associated with known virulence factors and, except for the food poisoning associated clade, were present across the phylogenetic diversity identified to date for . Many strains associated with food poisoning lacked the genes for hyaluronidases and sialidases, important for attaching to and digesting complex carbohydrates found in animal tissues. Overall, the diversity of virulence factors in makes these species capable of causing disease in a wide variety of hosts and niches.
是一种机会性致病细菌,可感染动物和人类。其基因组编码多种毒素和毒力蛋白,随着更多基因组被测序,这一列表还在不断扩充。在本研究中,对从患病牛肠道组织以及患病和健康鸡群的肉鸡中分离出的44株菌株的基因组进行了测序。通过使用BLASTp比对组装序列中的已知毒素和毒力蛋白序列,将这些新组装的基因组与141个公开可用的基因组组装进行了比较。在所分析的至少99%的组装中存在α毒素、胶原酶、唾液酸酶()和α - 肉毒蛋白酶的基因。相比之下,B、C、D和E型毒素型的β毒素、ε毒素、ι毒素和二元肠毒素在所分析的组装中不到5%。检测到了β2毒素的其他序列变体,其中一些缺少前导或信号肽序列,因此可能不会被分泌。一些参与肠道疾病的成孔毒素与宿主相关,基因仅在禽类分离株中发现,而、和仅存在于犬类和马类分离株中。肺泡溶素与犬类和马类菌株呈正相关,且仅存在于一个单系分支中。反刍动物来源的菌株与已知毒力因子无关,除了与食物中毒相关的分支外,存在于迄今为止确定的整个系统发育多样性中。许多与食物中毒相关的菌株缺乏透明质酸酶和唾液酸酶基因,这些基因对于附着和消化动物组织中发现的复杂碳水化合物很重要。总体而言,毒力因子的多样性使这些物种能够在广泛的宿主和生态位中引起疾病。