Cardoso Emanuela Mendes, Dea Lindner Juliano De, Ferreira Fabienne Antunes
Bacterial Molecular Genetics Laboratory (GeMBac), Department of Microbiology, Immunology, and Parasitology, Biological Sciences Center, Universidade Federal de Santa Catarina (UFSC), Campus Universitário Reitor João David Ferreira Lima, Trindade, Florianópolis, SC, 88040-960, Brazil.
Food Technology and Bioprocess Research Group, Department of Food Science and Technology, Agricultural Sciences Center, UFSC, Rodovia Admar Gonzaga, 1346. Itacorubi., Florianópolis, SC, 88034-001, Brazil.
Braz J Microbiol. 2024 Dec;55(4):4129-4137. doi: 10.1007/s42770-024-01544-2. Epub 2024 Oct 23.
The rapid expansion of broiler chicken production in Brazil has presented significant sanitation challenges within the poultry industry. Among these challenges, Salmonella enterica subsp. enterica serotype Heidelberg stands as a contributor to global salmonellosis outbreaks. This study analyzed 13 draft genomes of Salmonella Heidelberg isolated from the pre-slaughter broiler chickens farms in Brazil. By conducting in silico analysis of these genomes, the study investigated genome similarity based on single nucleotide polymorphisms (SNPs) and identified genes encoding resistance to antimicrobials, sanitizers, and virulence factors. Furthermore, mobile genetic elements (MGE) were identified to assess their potential role in propagating genes through horizontal gene transfer. A risk classification was also applied based on the resistomes. The genomes revealed a high prevalence of genes conferring resistance to aminoglycosides, fosfomycin, sulfonamides, tetracycline, and genes linked to quaternary ammonium resistance. The study also uncovered six Salmonella pathogenicity islands (SPI) and over 100 genes encoding virulence factors. The association of MGE with antibiotic-resistant genes sul2 and blaCMY-2 raised concerns about the potential transfer to other bacteria, posing a substantial risk for spreading resistance mechanisms according to established risk protocols. Additionally, SNP analysis indicated close phylogenetic relationships among some isolates, suggesting a common origin. This study enhances our understanding of Salmonella Heidelberg strains by identifying key risk factors for transmission and revealing the association between resistance genes and MGEs. This insight provides a foundation for developing and implementing effective control, monitoring, and treatment strategies in the poultry industry.
巴西肉鸡生产的迅速扩张给家禽业带来了重大的卫生挑战。在这些挑战中，肠炎沙门氏菌肠炎亚种海德堡血清型是全球沙门氏菌病暴发的一个促成因素。本研究分析了从巴西肉鸡屠宰前农场分离出的13株海德堡沙门氏菌的基因组草图。通过对这些基因组进行计算机分析，该研究基于单核苷酸多态性（SNP）调查了基因组相似性，并鉴定了编码对抗菌药物、消毒剂和毒力因子耐药性的基因。此外，还鉴定了可移动遗传元件（MGE），以评估它们在通过水平基因转移传播基因方面的潜在作用。还根据耐药基因组进行了风险分类。这些基因组显示，赋予对氨基糖苷类、磷霉素、磺胺类、四环素耐药性的基因以及与季铵盐耐药性相关的基因普遍存在。该研究还发现了6个沙门氏菌致病岛（SPI）和100多个编码毒力因子的基因。MGE与抗生素耐药基因sul2和blaCMY - 2的关联引发了对其可能转移至其他细菌的担忧，根据既定的风险协议，这对耐药机制的传播构成了重大风险。此外，SNP分析表明一些分离株之间存在密切的系统发育关系，表明它们有共同的起源。本研究通过识别传播的关键风险因素以及揭示耐药基因与MGE之间的关联，增强了我们对海德堡沙门氏菌菌株的理解。这一见解为在家禽业制定和实施有效的控制、监测及治疗策略奠定了基础。
