Chryseobacterium antibioticum sp. nov. with antimicrobial activity against Gram-negative bacteria, isolated from Arctic soil.

A yellow-pigmented, non-motile, Gram-stain-negative, pleomorphic bacterium, designated RP-3-3T was obtained from soil sampled at the Arctic region in Cambridge Bay, NU, Canada. The strain is strictly aerobic, psychrotolerant, grow optimally at 15-20 °C and produces flexirubin type pigments. The strain is able to hydrolyse CM-cellulose, casein, starch and DNA. Strain RP-3-3T showed antimicrobial activity against Gram-negative pathogens. A phylogenetic analysis based on its 16S rRNA gene sequence revealed that strain RP-3-3T formed a lineage within the family Weeksellaceae and clustered as members of the genus Chryseobacterium. The closest members were Chryseobacterium shigense DSM 17126T (98.7% sequence similarity), Chryseobacterium carnipullorum DSM 25581T (98.7%) and Chryseobacterium oncorhychi 701B-08T (98%). The genome is 4,910,468 bp long with 73 scaffolds and 4300 protein-coding genes. The anti-SMASH analysis of whole genome showed ten putative biosynthetic gene clusters responsible for various secondary metabolites. The sole respiratory quinone is MK-6. The major cellular fatty acids are iso-C15:0, iso-C17:1 ω9c, iso-C17:0 3-OH, summed feature 3 (iso-C15 :0 2-OH/C16 :1ω7c) and anteiso-C15:0. The major polar lipid is phosphatidylethanolamine. The DNA G + C content of the type strain is 36.9 mol%. In addition, the average nucleotide identity and in silico DNA-DNA hybridization  relatedness values between strain RP-3-3T and phylogenetically closest members are below the threshold value for species delineation. Based on genomic, chemotaxonomic, phenotypic and phylogenetic analyses, strain RP-3-3T represents novel species in the genus Chryseobacterium, for which the name Chryseobacterium antibioticum sp. nov. is proposed. The type strain is RP-3-3T (=KACC 21620T = NBRC 114360T).