ARC Centre of Excellence in Synthetic Biology, School of Natural Sciences, Macquarie University, North Ryde, NSW, 2113, Australia.
School of Natural Sciences, Macquarie University, North Ryde, NSW, 2113, Australia.
Nat Commun. 2023 Feb 9;14(1):702. doi: 10.1038/s41467-023-36252-2.
Acinetobacter baumannii and Klebsiella pneumoniae are opportunistic pathogens frequently co-isolated from polymicrobial infections. The infections where these pathogens co-exist can be more severe and recalcitrant to therapy than infections caused by either species alone, however there is a lack of knowledge on their potential synergistic interactions. In this study we characterise the genomes of A. baumannii and K. pneumoniae strains co-isolated from a single human lung infection. We examine various aspects of their interactions through transcriptomic, phenomic and phenotypic assays that form a basis for understanding their effects on antimicrobial resistance and virulence during co-infection. Using co-culturing and analyses of secreted metabolites, we discover the ability of K. pneumoniae to cross-feed A. baumannii by-products of sugar fermentation. Minimum inhibitory concentration testing of mono- and co-cultures reveals the ability for A. baumannii to cross-protect K. pneumoniae against the cephalosporin, cefotaxime. Our study demonstrates distinct syntrophic interactions occur between A. baumannii and K. pneumoniae, helping to elucidate the basis for their co-existence in polymicrobial infections.
鲍曼不动杆菌和肺炎克雷伯菌是经常从混合感染中共同分离出来的机会性病原体。与由单一物种引起的感染相比，这些病原体共存的感染可能更严重且更难以治疗，但我们对它们潜在的协同相互作用知之甚少。在这项研究中，我们对从单个人类肺部感染中共同分离出的鲍曼不动杆菌和肺炎克雷伯菌菌株的基因组进行了表征。我们通过转录组、表型和表型测定研究了它们相互作用的各个方面，为了解它们在共同感染期间对抗菌药物耐药性和毒力的影响奠定了基础。通过共培养和分泌代谢物分析，我们发现肺炎克雷伯菌能够通过糖发酵的副产物为鲍曼不动杆菌提供交叉喂养。单培养和共培养的最小抑菌浓度测试表明，鲍曼不动杆菌能够保护肺炎克雷伯菌免受头孢菌素头孢噻肟的侵害。我们的研究表明，鲍曼不动杆菌和肺炎克雷伯菌之间存在明显的共生相互作用，有助于阐明它们在混合感染中共存的基础。
