Mannheimia varigena and closely related Group V Mannheimia isolate genome sequencing and assembly

Mannheimia haemolytica is historically the predominant bacterial species isolated from cattle with respiratory disease and isolates with antimicrobial resistance (AMR) genes have been well characterized. However, Mannheimia varigena also causes respiratory disease in cattle and some isolates have demonstrable antibiotic resistance. Group V Mannheimia are distinct from both M. haemolytica and M. varigena, and have not been assigned to a species at present. Group V Mannheimia are found in cattle, however, their role and propensity for causing respiratory disease is not fully understood, not is the extent to which they may harbor AMR genes. The goals of this study were to sequence the genomes of M. varigena and Group V Mannheimia isolates, the majority of which were obtained through the sampling of cattle lungs afflicted with respiratory disease. Availability of these genomes may facilitate analyses for AMR genes, including those that may reside on integrative conjugative elements, as well as conservation, or lack thereof, of genes or pathways involved in pathogenesis.

溶血性曼海姆菌（Mannheimia haemolytica）历史上是从患呼吸道疾病的牛体内分离出的主要病原菌，携带抗菌药物耐药性（antimicrobial resistance, AMR）基因的分离株已得到充分表征。然而，变异曼海姆菌（Mannheimia varigena）同样可引发牛呼吸道疾病，部分分离株表现出明确的抗生素耐药性。V组曼海姆菌（Group V Mannheimia）与溶血性曼海姆菌和变异曼海姆菌均存在显著差异，目前尚未被归类为独立物种。该类菌群可在牛体内检出，但其引发呼吸道疾病的作用与致病易感性尚未完全明确，其携带AMR基因的程度也尚不清晰。本研究的目标为对变异曼海姆菌和V组曼海姆菌分离株的基因组进行测序，其中大部分分离株均取自患呼吸道疾病的牛肺组织样本。上述基因组的公开可用将有助于开展AMR基因相关分析，包括对位于整合接合元件上的耐药基因的研究，同时也可助力解析致病相关基因或通路的保守性及其缺失情况。