Mucilaginibacter metallidurans sp. nov., isolated from a gold and copper mine

In this study, a novel strain P4^T was isolated from a soil sample collected in Longyan, Fujian, PR China. Phylogeny based on 16S rRNA gene sequences suggested that strain P4^T is a new member of the genus Mucilaginibacter. The novel strain showed the highest 16S rRNA gene sequence similarity to Mucilaginibacter rubeus EF23^T (98.4%). The average nucleotide identity and digital DNA-DNA hybridization values between strain P4^T and M. rubeus EF23^T were 93.75% and 66.10%, respectively, and between P4^T and Mucilaginibacter gossypii Gh-67^T were 95.11% and 69.20%, respectively, which were below the prokaryotic species delineation thresholds, suggesting that strain P4^T is a novel species within the genus Mucilaginibacter. The primary fatty acids detected in strain P4^T included summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), iso-C_15:0 and C_16:0. The major respiratory quinone in strain P4^T was Menaquinone-7 (MK-7). The high level of phosphatidylethanolamine, along with the presence of multiple other unknown phospholipids like PL1 and PL2, highlights a distinctive membrane composition in strain P4^T. Combined with results stemming from the determination of physical and biochemical characteristics, chemical properties and genome analysis, strain P4^T is proposed to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter metallidurans sp. nov. is proposed. The type strain is P4^T (=MCCC 1K09773^T=KCTC 102379^T), with the complete genome and 16S rRNA gene sequence deposited in National Center for Biotechnology Information (NCBI) under GenBank accession numbers CP043449.1 and PV576010, respectively.