Taxonomic characterization of Sphaerotilus microaerophilus sp. nov., a sheath-forming microaerophilic bacterium of activated sludge origin

• DOI: 10.1007/s00203-024-03991-9
• Publication Date: 2024-05-10T09:02:19Z
• Authors: Shiori Narihara; Shun Chida; Naoki Matsunaga; Ryosuke Akimoto; Mizuki Akimoto; Aoi Hagio; Tomomi Mori; Tadashi Nittami; Michio Sato; Sehui Mun; Hyeonjin Kang; Ji Hwan Back; Minoru Takeda
• Keywords: Microaerophile; Strain (injury); Genome size; genomic DNA

Abstract A microaerophilic Gram-stain-negative bacilliform bacterial strain, FB-5 T , was isolated from activated sludge in Yokohama, Japan, that exhibited filamentous growth and formed a microtube (sheath). Cells were motile using single polar flagellum. The optimum temperature pH 30 °C 7.5, respectively. Strain catalase-negative. Peptides amino acids utilized as energy carbon sources. Sugars organic not utilized. Vitamin B 12 enhanced the of strain . Sulfur-dependent lithotrophic possible. Major respiratory quinone UQ-8. fatty C 16:1 ω7 16:0 genomic DNA G + content 69.16%. Phylogenetic analysis 16S rRNA gene suggested belongs to genus Sphaerotilus close relatives S. natans subsup. sulfidivorans with 98.0% 97.8% similarity based on analysis, genome size (6.06 Mbp) larger than (4.39–5.07 strains. AAI values against related strains ranged 71.0 72.5%. range ANI 81.7 − 82.5%. In addition these distinguishable features genome, core dDDH analyses this is novel member Based its physiological properties features, considered species for which name microaerophilus sp. nov. proposed. type (= JCM 35424 = KACC 23146 ).