Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany.
Research Group Translational Bioinformatics, Institute for Biostatistics and Informatics in Medicine and Aging Research, Rostock University Medical Center, Rostock, Germany.
Front Cell Infect Microbiol. 2024 Oct 24;14:1433783. doi: 10.3389/fcimb.2024.1433783. eCollection 2024.
can both be a helpful colonizer of the human skin as well as the causative agent of acne and purulent infections. Until today, it is a moot point whether there are strains exclusively devoted to be part of the skin microbiome and others, that carry special features enabling them to cause disease. So far, the search for the molecular background of such diverse behavior has led to inconsistent results.
In the present study, we prospectively collected strains from 27 infected persons and 18 healthy controls employing rigid selection criteria to ensure their role as infectious agent or colonizer. The genome sequences from these strains were obtained and carefully controlled for quality.
Deduced traditional phylotyping assigned almost all superficial isolates to type IA1, while the clinical strains were evenly distributed between types IA1, IB, and II. Single locus sequence typing (SLST) showed a predominance of A1 type for the control strains, whereas 56% of the clinical isolates belonged to types A1, H1 and K8. Pangenome analysis from all the present strains and 30 published genomes indicated the presence of an open pangenome. Except for three isolates, the colonizing strains clustered in clades separate from the majority of clinical strains, while 4 clinical strains clustered with the control strains. Identical results were obtained by a single nucleotide polymorphism (SNP) analysis. However, there were no significant differences in virulence gene contents in both groups.
Genome-wide association studies (GWAS) from both the pangenome and SNP data consistently showed genomic differences between both groups located in metabolic pathway and DNA repair genes. Thus, the different behavior of colonizing and infectious C. acnes strains could be due to special metabolic capacities or flexibilities rather than specific virulence traits.
痤疮丙酸杆菌既能定植于人体皮肤，又能引发痤疮和化脓性感染。直到今天，是否存在专门定植于皮肤微生物群的菌株，以及具有特殊特征使其能够致病的菌株，这仍然存在争议。到目前为止，对这种多样化行为的分子背景的研究尚未得出一致的结果。
本研究前瞻性地从 27 名感染患者和 18 名健康对照中采集了菌株，采用严格的选择标准以确保其作为感染因子或定植菌的作用。从这些菌株中获得了基因组序列，并仔细控制了质量。
传统的推断型系统发育分析将几乎所有的浅层分离株都归类为 IA1 型，而临床菌株则均匀分布在 IA1、IB 和 II 型之间。单基因座序列分型（SLST）显示，对照菌株以 A1 型为主，而 56%的临床分离株属于 A1、H1 和 K8 型。对所有本研究菌株和 30 个已发表基因组的泛基因组分析表明存在一个开放的泛基因组。除了三个分离株外，定植菌聚类在与大多数临床菌株分离的分支之外，而 4 个临床菌株与对照菌株聚类在一起。单核苷酸多态性（SNP）分析也得到了相同的结果。然而，两组的毒力基因含量没有显著差异。
来自泛基因组和 SNP 数据的全基因组关联研究（GWAS）一致表明，两组之间存在位于代谢途径和 DNA 修复基因中的基因组差异。因此，定植菌和感染性痤疮丙酸杆菌菌株的不同行为可能是由于特殊的代谢能力或灵活性，而不是特定的毒力特征。
