Staphylococcus edaphicus sp. nov., Isolated in Antarctica, Harbors the mecC Gene and Genomic Islands with a Suspected Role in Adaptation to Extreme Environments

• Published in: Applied and Environmental Microbiology
• Main Authors: Pantůček, Roman, Sedláček, Ivo, Indráková, Adéla, Vrbovská, Veronika, Mašlaňová, Ivana, Kovařovic, Vojtěch, Švec, Pavel, Králová, Stanislava, Krištofová, Lucie, Kekláková, Jana, Petráš, Petr, Doškař, Jiří
• Other Authors: Drake, Harold L., Ministerstvo Zdravotnictví Ceské Republiky, Ministerstvo Školství, Mládeže a Tělovýchovy
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Society for Microbiology 2018
• Subjects: Antarc*; Antarctica; James Ross Island; Ross Island
• Online Access: http://dx.doi.org/10.1128/aem.01746-17; https://journals.asm.org/doi/pdf/10.1128/AEM.01746-17

ABSTRACT Two Gram-stain-positive, coagulase-negative staphylococcal strains were isolated from abiotic sources comprising stone fragments and sandy soil in James Ross Island, Antarctica. Here, we describe properties of a novel species of the genus Staphylococcus that has a 16S rRNA gene sequence nearly identical to that of Staphylococcus saprophyticus . However, compared to S. saprophyticus and the next closest relatives, the new species demonstrates considerable phylogenetic distance at the whole-genome level, with an average nucleotide identity of <85% and inferred DNA-DNA hybridization of <30%. It forms a separate branch in the S. saprophyticus phylogenetic clade as confirmed by multilocus sequence analysis of six housekeeping genes, rpoB , hsp60 , tuf , dnaJ , gap , and sod . Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) and key biochemical characteristics allowed these bacteria to be distinguished from their nearest phylogenetic neighbors. In contrast to S. saprophyticus subsp. saprophyticus , the novel strains are pyrrolidonyl arylamidase and β-glucuronidase positive and β-galactosidase negative, nitrate is reduced, and acid produced aerobically from d -mannose. Whole-genome sequencing of the 2.69-Mb large chromosome revealed the presence of a number of mobile genetic elements, including the 27-kb pseudo-staphylococcus cassette chromosome mec of strain P5085 T (ψSCC mec P5085 ), harboring the mecC gene, two composite phage-inducible chromosomal islands probably essential to adaptation to extreme environments, and one complete and one defective prophage. Both strains are resistant to penicillin G, ampicillin, ceftazidime, methicillin, cefoxitin, and fosfomycin. We hypothesize that antibiotic resistance might represent an evolutionary advantage against beta-lactam producers, which are common in a polar environment. Based on these results, a novel species of the genus Staphylococcus is described and named Staphylococcus edaphicus sp. nov. The type strain is ...