Macrococcus canis sp. nov., a skin bacterium associated with infections in dogs

Abstract

Gram-stain-positive cocci were isolated from miscellaneous sites of the skin of healthy dogs as well as from infection sites in dogs. The closest relative by sequencing of the 16S rRNA gene was Macrococcus caseolyticus with 99.7 % sequence identity, but compared with M. caseolyticus, the novel strains shared only 90.8 to 93.5 % DNA sequence identity with cpn60, dnaJ, rpoB and sodA partial genes, respectively. The novel strains also exhibited differential phenotypic characteristics from M. caseolyticus, and the majority displayed a visible haemolysis on sheep blood agar, while M. caseolyticus did not have any haemolytic activity. They generated different matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) MS spectral profiles compared with the other species of the genus Macrococcus. Furthermore, strain KM 45013^T shared only 53.7 % DNA-DNA relatedness with the type strain of M. caseolyticus, confirming that they do not belong to the same species. The DNA G+C content of strain KM 45013^T was 36.9 mol%. The most abundant fatty acids were C14 : 0, C18 : 3ω6c (6, 9, 12) and C16 : 0 n alcohol. MK-6 was the menaquinone type of KM 45013^T. Cell-wall structure analysis revealed that the peptidoglycan type was A3α l-Lys-Gly2-l-Ser. Based on genotypic and chemotaxonomic characteristics, we propose to classify these strains within a novel species of the genus Macrococcus for which the name Macrococcus canis sp. nov. is proposed. The type strain is KM 45013^T (=DSM 101690^T=CCOS 969^T=CCUG 68920^T).

Keywords: Gram-positive; Staphylococcaceae; animals; cocci.