Webster John, Bowring Bethany, Stroud Leah, Marsh Ian, Sales Narelle, Bogema Daniel
NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute PMB 4008, Narellan, NSW 2570, Australia.
Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, Westmead, NSW 2145, Australia.
Microorganisms. 2023 Jan 23;11(2):297. doi: 10.3390/microorganisms11020297.
is a bacterial pathogen that is the causative agent of erysipelas in a variety of animals, including swine, emus, turkeys, muskox, caribou, moose, and humans. This study aims to investigate the population structure and genomic features of Australian isolates of in the Australian pig industry and compare them to the broader scope of isolates worldwide. A total of 178 isolates (154 Australian, seven vaccine isolates, six international isolates, and 11 of unknown origin) in this study were screened against an MLST scheme and publicly available reference isolates, identifying 59 new alleles, with isolates separating into two main single locus variant groups. Investigation with BLASTn revealed the presence of the gene in 171 (96%) of the isolates, with three main groups of SpaA protein sequences observed amongst the isolates. Novel SpaA protein sequences, categorised here as group 3 sequences, consisted of two sequence types forming separate clades to groups 1 and 2, with amino acid variants at positions 195 (D/A), 303 (G/E) and 323(P/L). In addition to the newly identified groups, five new variant positions were identified, 124 (S/N), 307 (Q/R), 323 (P/L), 379 (M/I), and 400 (V/I). Resistance screening identified genes related to lincomycin, streptomycin, erythromycin, and tetracycline resistance. Of the 29 isolates carrying these resistance genes, 82% belonged to SpaA group 2-N101S ( = 22) or 2-N101S-I257L ( = 2). In addition, 79% ( = 23) of these 29 isolates belonged to MLST group ST 5. Our results illustrate that Australia appears to have a unique diversity of isolates in pig production industries within the wider global context of isolates.
是一种细菌病原体，是多种动物（包括猪、鸸鹋、火鸡、麝牛、北美驯鹿、驼鹿和人类）丹毒的病原体。本研究旨在调查澳大利亚养猪业中该菌澳大利亚分离株的种群结构和基因组特征，并将其与全球范围内更广泛的分离株进行比较。本研究共筛选了178株分离株（154株澳大利亚分离株、7株疫苗分离株、6株国际分离株和11株来源不明的分离株），采用多位点序列分型（MLST）方案和公开可用的参考分离株进行检测，鉴定出59个新等位基因，分离株分为两个主要的单基因座变异组。通过BLASTn分析发现，171株（96%）分离株中存在该基因，在分离株中观察到三种主要的SpaA蛋白序列组。新的SpaA蛋白序列，在此归类为第3组序列，由两种序列类型组成，与第1组和第2组形成单独的进化枝，在第195位（D/A）、第303位（G/E）和第323位（P/L）有氨基酸变异。除了新鉴定的组外，还鉴定出五个新的变异位点，分别为第124位（S/N）、第307位（Q/R）、第323位（P/L）、第379位（M/I）和第400位（V/I）。耐药性筛选鉴定出与林可霉素、链霉素、红霉素和四环素耐药相关的基因。在携带这些耐药基因的29株分离株中，82%属于SpaA第2组-N101S（n = 22）或2-N101S-I257L（n = 2）。此外，这29株分离株中有79%（n = 23）属于MLST第5组。我们的结果表明，在全球范围内分离株的大背景下，澳大利亚养猪业中的该菌分离株似乎具有独特的多样性。
