Lotipaludicoccus stagni gen. nov., sp. nov., within the Family Opitutaceae, Isolated from a Lotus Wetland

A Gram-stain negative, aerobic, non-motile, coccoid bacterium, designated IMCC34717^T, was isolated from a lotus wetland in the Republic of Korea. Strain IMCC34717^T grew at 15-38 °C (optimum, 30 °C), at pH 6.0-9.0 (optimum, pH 7.0), and in the presence of 0-0.7% (w/v) NaCl (optimum, 0.5% NaCl). Phylogenetic analysis of 16S rRNA genes placed strain IMCC34717^T within the family Opitutaceae, showing highest sequence similarity (95.2%) to Nibricoccus aquaticus HZ-65^T. The complete whole-genome was 3.56 Mbp in size with a DNA G + C content of 61.8%. Overall genomic relatedness indices between strain IMCC34717^T and members of the family Opitutaceae were at or below the proposed genus thresholds, and the genome-based phylogenetic trees revealed a distinct phylogenetic separation from known genera, supporting its recognition as a representative of a novel genus. Genomic analysis revealed pathways for nitrogen, sulfur, and carbon metabolism, including unique amylase-related genes absent from closely related species, Nibricoccus aquaticus, suggesting ecological specialization of the strain. The major respiratory quinone was menaquinone-7 (MK-7), and the predominant cellular fatty acids were iso-C_14:0 (28.1%), C_16:0 (25.1%), and anteiso-C_15:0 (21.6%). The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminophospholipid, and three unidentified lipids. On the basis of phylogenetic, genomic, and phenotypic evidence, strain IMCC34717^T is considered to represent a novel genus and species of the family Opitutaceae, for which the name Lotipaludicoccus stagni gen. nov., sp. nov. is proposed. The type strain is IMCC34717^T (= KCTC 82067^T = KACC 23134^T = NBRC 113911^T).