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Two Corynebacterium species were proposed decades ago, isolated from clinical samples and divided into biovars: "Corynebacterium genitalium" biovars I-V and "Corynebacterium pseudogenitalium" biovars C1-C6. Several biovars have been re-classified as new species. Nevertheless, biovar I and C5, together with their respective specific epithets "Corynebacterium genitalium" and "Corynebacterium pseudogenitalium", remained not validly published after more than 40 years. Several more strains, temptatively classified as "C. genitalium" biovar I and "Corynebacterium pseudogenitalium" C5, have been isolated from clinical and environmental samples. Both species presented Gram-positive, non-spore forming rod-shaped cells, able to grow aerobically with CO 2 . Core-genome analysis identified "C. genitalium" to be most closely related to Corynebacterium tuscaniense, Corynebacterium urinipleomorphum, Corynebacterium aquatimens and C appendicis, and Corynebacterium gottingense as the most closely related species to "C. pseudogenitalium". Comprehensive genomic, genotypic, phenotypic analyses, as well as chemotaxonomic, support the proposal for "C. genitalium" and "C. pseudogenitalium" as distinct species within the genus Corynebacterium. The designated type strains of the two species are Furness 392-1 T  = ATCC 33030 T  = CCUG 38989 T  = CCM 9178 T  = DSM 113155 T for C. genitalium sp. nov., nom. rev., and Furness 162-C2 T  = ATCC 33039 T  = CCUG 27540 T  = CCM 9177 T  = DSM 113154 T for C. pseudogenitalium sp. nov., nom. rev., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Capnocytophaga canimorsus is a dog oral commensal bacterium that causes rare but life-threatening generalized infections in humans who have been in contact with its animal hosts. Two other dog commensals, Capnocytophaga canis and Capnocytophaga cynodegmi, cause rare, mild local infections. To date, nine capsular serovars have been described in C. canimorsus. Here, we serotyped 112 strains of Capnocytophaga spp. isolated from human infections. The C. canimorsus strains (86 of 96, 89.6%) belonged to serovars A, B, or C with relative frequencies of approximately 30% for each serovar. The high prevalence of the A, B, and C serovars in strains isolated from humans, compared to the previously described low prevalence of these serovars among dog isolates (7.6%), confirms that these three serovars are more virulent to humans than other serovars and suggests that the low incidence of disease may be linked to the low prevalence of the A, B, and C serovars in dogs. We serotyped six strains of C. canis and ten strains of C. cynodegmi and, surprisingly, found one C. canis and three C. cynodegmi strains to be of capsular serovar B. This observation prompted us to test 34 dog-isolated C. canis and 16 dog-isolated C. cynodegmi strains. We found four C. canis strains belonging to serovar A and one belonging to serovar F. In contrast, no dog-isolated C. cynodegmi strain could be typed with the available antisera. This work demonstrates that virulence-associated capsular polysaccharides (A, B, and C) are not specific to the C. canimorsus species.

Two strains included in a whole-genome sequencing project for methicillin-resistant Staphylococcus aureus (MRSA) were identified as non- Staphylococcus aureus when the sequences were analysed using the bioinformatics software ALEX (www.1928diagnostics.com, Gothenburg, Sweden). Sequencing of the sod A gene of these strains identified them as Staphylococcus argenteus . The collection of MRSA in western Sweden was checked for additional strains of this species. A total of 18 strains of S. argenteus isolated between 2011 and December 2017 were identified.

Phenotypic and phylogenetic studies were performed on two strains of a hitherto undescribed Aerococcus-like organism isolated from the human vagina. Comparative 16S rRNA gene sequencing studies demonstrated that the unknown strains constitute a new subline within the genus Aerococcus. The unknown bacterium was readily distinguished from the two currently recognized Aerococcus species, Aerococcus viridans and Aerococcus urinae, by biochemical tests and electrophoretic analysis of whole-cell proteins. On the basis of phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Aerococcus christensenii sp. nov. The type strain of A. christensenii is CCUG 28831T.

Phenotypic and phylogenetic studies were performed on an unknown Gram-positive catalase-negative coccus isolated from a common otter (Lutra lutra). Comparative 16S rRNA gene sequencing demonstrated that the unknown bacterium represents a new subline within the genus Vagococcus, close to, but distinct from, Vagococcus fluvialis and Vagococcus salmoninarum. The unknown bacterium was readily distinguished from the two currently recognized Vagococcus species by biochemical tests and electrophoretic analysis of whole-cell proteins. Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium be classified as a new species, Vagococcus lutrae, the type strain of which is CCUG 39187T.

Eleven strains of a hitherto undescribed Gram-positive, catalase-negative, facultatively anaerobic rod-shaped bacterium from human sources and medical care products were characterized by phenotypic and molecular taxonomic methods. The phenotypic properties of the bacterium were consistent with its assignment to the genus Lactobacillus but it was readily distinguished from all currently described species of this genus by its biochemical characteristics and by SDS-PAGE analysis of its cellular proteins. Comparative 16S rRNA gene sequence analysis demonstrated that the unknown bacterium was a member of rRNA group I Lactobacillus which includes Lactobacillus delbrueckii, the type species of the genus, and close relatives. Lactobacillus gasseri and Lactobacillus johnsonii were the nearest phylogenetic relatives of the unknown bacterium, but 16S rRNA sequence divergence values of > 4% clearly showed that it represents a distinct species. Based on both phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium should be classified in the genus Lactobacillus, as Lactobacillus iners sp. nov. The type strain of Lactobacillus iners is CCUG 28746T.