sp. nov., a Fermenting Bacterium Isolated from a Petroleum Reservoir in Azerbaijan, and Emended Description of the Genus .

A methanogenic enrichment growing on a medium with methanol was obtained from a petroleum reservoir (Republic of Azerbaijan) and stored for 33 years without transfers to fresh medium. High-throughput sequencing of the V4 region of the 16S rRNA gene revealed members of the genera , , , , , and . A novel gram-positive, rod-shaped, anaerobic fermentative bacterium, strain 1933P, was isolated from this enrichment and characterized. The strain grew at 13-55 °C (optimum 35 °C), with 0-3.0% (/) NaCl (optimum 0-2.0%) and in the pH range of 6.7-8.0 (optimum pH 7.0). The 16S rRNA gene sequence similarity, the average nucleotide identity (ANI) and in silico DNA-DNA hybridization (dDDH) values between strain 1933P and the type strain of the most closely related species DSM 12858 were 98.5%, 70.5%, and 22.6%, respectively, and were below the threshold accepted for species demarcation. Genome-based phylogenomic analysis and physiological and biochemical characterization of the strain 1933P (VKM B-3382 = KCTC 15984) confirmed its affiliation to a novel species of the genus , for which the name sp. nov. is proposed. Genome analysis suggests that the new strain has potential in the degradation of proteinaceous components.