Tamlana flava sp. nov., isolated from mangrove sediment and genome-based taxonomic analysis of the genus Tamlana.

A novel yellow-coloured bacterial strain MA10^T was isolated from mangrove sediment and subjected to polyphasic taxonomic identification. Strain MA10^T was Gram-negative, rod-shaped, catalase-positive and oxidase-positive. Carotenoid pigment was present, and flexirubin-type pigment was absent. The 16S rRNA gene of strain MA10^T had the highest sequence similarity with Tamlana crocina HST1-43^T of 94.5%. The genome size was 3.77 Mbp with a genomic G+C content of 36.3%. The phylogenetic analysis of the 16S rRNA gene sequence and whole-genome sequence showed that strain MA10^T belonged to the genus Tamlana of the family Flavobacteriaceae and tightly clustered with T. crocina HST1-43^T. The digital DNA-DNA hybridization value and average nucleotide identity value between strain MA10^T and T. crocina HST1-43^T were 20.4 and 76.7%, respectively. The major menaquinone was MK-6. The major fatty acids (>10 %) were iso-C_15:0 (41.6%) and iso-C_15:1 G (16.8%). The polar lipids consisted of phosphatidylethanolamine, two unidentified aminolipids and three unidentified lipids. Based on the present polyphasic taxonomic study, strain MA10^T was considered to represent a novel species of the genus Tamlana, for which the name Tamlana flava sp. nov. was proposed. The type strain was MA10^T (=MCCC 1K09289^T=KCTC 102321^T). Additionally, the phylogeny of the 16S rRNA gene and whole-genome sequences found that the hitherto described nine species of the genus Tamlana and Algibacter onchidii presented polyphyletic clades, which could be divided into five different genera. The average amino acid identity value of 80% was chosen as the boundary of the five genera. Thus, except for the genus Tamlana, four novel genera named Allotamlana gen. nov., Cognatitamlana gen. nov., Neotamlana gen. nov. and Pseudotamlana gen. nov. were proposed. This study provided valuable taxonomic analysis of the genus Tamlana.