Veterinary Diagnostic Laboratory, North Dakota State University, Fargo, ND, USA; College of Public Health, University of South Florida, Tampa, FL, USA.
Veterinary Diagnostic Laboratory, North Dakota State University, Fargo, ND, USA.
J Microbiol Methods. 2024 Dec;227:107067. doi: 10.1016/j.mimet.2024.107067. Epub 2024 Nov 2.
Pasteurella multocida capsular types A, D, and F cause disease in many animal hosts, including bovine respiratory disease in cattle, which is one of the most globally significant animal diseases. Additionally, P. multocida capsular types B and E cause haemorrhagic septicaemia, a devastating disease primarily of cattle, water buffalo, and bison that develops rapidly with high mortality. Haemorrhagic septicaemia mostly occurs in developing countries and has potential to emerge elsewhere in the world. The diagnosis of haemorrhagic septicaemia currently requires recognition of compatible gross or histologic lesions and serotyping or molecular characterization of strains. In this study, we performed genomic characterization of 84 P. multocida strains, which were then used to develop and validate a matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) biomarker-based method for differentiating non-haemorrhagic septicaemia strains of P. multocida from haemorrhagic septicaemia-causing strains. Haemorrhagic septicaemia strain types B:2,5, E:2,5, and B:3,4 were used to maximize diversity. Three automated classification models were generated and then used to develop an assisted model, which utilized two peaks (6419 and 7729 m/z) to accurately differentiate non-haemorrhagic septicaemia-causing strains from haemorrhagic septicaemia-causing strains of P. multocida. The assisted model performed with 98.2 % accuracy for non-haemorrhagic septicaemia strains, 100 % accuracy for classic B:2,5 and E:2,5 strains, and 84.4 % accuracy for combined haemorrhagic septicaemia-causing strains (B:2,5, E:2,5, and B:3,4) with an overall accuracy of 96.9 %. Our results suggest that MALDI-TOF MS may be used to routinely screen P. multocida isolated from diagnostic cases for initial identification of haemorrhagic septicaemia-causing strains, and to determine whether additional characterizations are warranted.
多杀巴斯德氏菌荚膜型 A、D 和 F 可引起许多动物宿主的疾病，包括牛的呼吸道疾病，这是全球最重要的动物疾病之一。此外，多杀巴斯德氏菌荚膜型 B 和 E 引起出血性败血症，这是一种主要发生在牛、水牛和野牛身上的破坏性疾病，其发展迅速，死亡率高。出血性败血症主要发生在发展中国家，并有在世界其他地方出现的潜力。出血性败血症的诊断目前需要识别相容的大体或组织学病变，并对菌株进行血清分型或分子特征分析。在这项研究中，我们对 84 株多杀巴斯德氏菌进行了基因组特征分析，然后利用这些菌株开发并验证了基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）生物标志物方法，用于区分多杀巴斯德氏菌的非出血性败血症菌株与引起出血性败血症的菌株。使用出血性败血症菌株 B:2,5, E:2,5 和 B:3,4 来最大限度地提高多样性。生成了三种自动分类模型，然后利用这些模型开发了一种辅助模型，该模型利用两个峰（6419 和 7729 m/z）来准确地区分非出血性败血症引起的菌株与引起出血性败血症的多杀巴斯德氏菌菌株。辅助模型对非出血性败血症菌株的准确率为 98.2%，对经典 B:2,5 和 E:2,5 菌株的准确率为 100%，对组合出血性败血症菌株（B:2,5, E:2,5 和 B:3,4）的准确率为 84.4%，总体准确率为 96.9%。我们的结果表明，MALDI-TOF MS 可用于常规筛选从诊断病例中分离出的多杀巴斯德氏菌，以初步鉴定引起出血性败血症的菌株，并确定是否需要进一步的特征分析。
