Evidence of in vitro mecB -mediated β-lactam antibiotic resistance transfer to Staphylococcus aureus from Macrococcus psychrotolerans sp. nov., a psychrophilic bacterium from food-producing animals and human clinical specimens

作者：Ivana Mašlaňová, Vojtěch Kovařovic, Tibor Botka, Pavel Švec, Ivo Sedláček, Ondřej Šedo, Adéla Finstrlová, Meina Neumann‐Schaal, Sarah Kirstein, Sybille Schwendener, Eva Staňková, Kristína Rovňáková, Petr Petřáš, Jiřı́ Doškař, Vincent Perreten, Roman Pantůček · 发表于：Applied and Environmental Microbiology · 年份：2025 · DOI：10.1128/aem.01652-24 · 被引用次数：7 · 研究领域：Antimicrobial Resistance in Staphylococcus、Bacterial Identification and Susceptibility Testing、Probiotics and Fermented Foods

ABSTRACT Macrococci are usually found as commensals on the skin and mucosa of animals and have been isolated from mammal-derived fermented foods; however, they can also act as opportunistic pathogens. Here, we used whole-genome sequencing, comparative genomics, extensive biotyping, MALDI-TOF mass spectrometry, and chemotaxonomy to characterize Macrococcus sp. strains isolated from livestock and human-related specimens. Based on the results of polyphasic taxonomy, we propose the species Macrococcus psychrotolerans sp. nov. (type strain NRL/St 95/376 T = CCM 8659 T = DSM 111350 T ) belonging to the Macrococcus caseolyticus phylogenetic clade. It grows at 4°C, and the core genome of the isolates contains suspected genes contributing to low-temperature tolerance. Variable genetic elements include prophages, chromosomal islands, a composite staphylococcal cassette chromosome island, and many plasmids that affect the overall genome expansion and adaptation to specific ecological settings of the studied isolates. Large plasmids carrying the methicillin resistance gene mecB were identified in M. psychrotolerans sp. nov. strains and confirmed as self-transmissible to Staphylococcus aureus in vitro . In addition to plasmids with circular topology, a 150-kb-long linear plasmid with 14.1-kb-long inverted terminal repeats, harboring many IS elements and putative genes for a type IV secretion system was revealed. The described strains were isolated from human clinical material, food-produc...