Genomic features of mecA-positive methicillin-resistant Mammaliicoccus sciuri causing fatal infections in pets admitted to a veterinary intensive care unit

Genomic and biological characteristics of a novel lytic phage, vB_MscM-PMS3, infecting the opportunistic zoonotic pathogen Mammaliicoccus sciuri

Mammaliicoccus sciuri is an opportunistic zoonotic pathogen in humans and animals. We isolated the Mammaliicoccus phage vB_MscM-PMS3, which was also able to infect and lyse M. sciuri and M. lentus. The phage genome is a linear dsDNA that is 147,811 bp in length and contains 206 ORFs and three tRNA genes. It showed low genome coverage (< 17%) and sequence identity (< 91.3%) to other phage genomes. Phylogenetic analysis based on the whole genome and major capsid protein revealed that this phage clustered with members of the subfamily Twortvirinae of the family Herelleviridae, but it was distinctly separated from the other members, indicating its uniqueness.

The Controversial Nature of Some Non-Starter Lactic Acid Bacteria Actively Participating in Cheese Ripening

This mini review deals with some controversial non-starter lactic acid bacteria (NSLAB) species known to be both human and animal pathogens but also health-promoting and probiotic. The focus is on Lactococcus garvieae, two Streptococcus species (S. uberis and S. parauberis), four Weissella species (W. hellenica, W. confusa, W. paramesenteroides, and W. cibaria), and Mammalicoccus sciuri, which worldwide, are often found within the microbiotas of different kinds of cheese, mainly traditional artisanal cheeses made from raw milk and/or relying on environmental bacteria for their ripening. Based on literature data, the virulence and health-promoting effects of these bacteria are examined, and some of the mechanisms of these actions are reviewed. Additionally, their possible roles in cheese ripening are also discussed. The analysis of the literature data available so far showed that, in general, the pathogenic and the beneficial strains, despite belonging to the same species, show somewhat different genetic constitutions. Yet, when the safety of a given strain is assessed, genomic analysis on its own is not enough, and a polyphasic approach including additional physiological and functional tests is needed.