Isolation and characterization ofSporomusa carbonissp. nov., a carboxydotrophic hydrogenogen in the genus ofSporomusaisolated from a charcoal burning pile

Abstract

A Gram-negative bacterial strain, designated ACPtT, was isolated from the covering top soil of an active charcoal burning pile. Cells of ACPtTwere strictly anaerobic, rod-shaped and grew optimally at 40°C and pH 7. The substrates ribose, glucose, sucrose, raffinose, melezitose, pyruvate, vanillate, syringate, methanol and CO were utilized for growth. Phylogenomic analysis of the 4.1 Mb genome showed that strain ACPt represented a novel species of the genusSporomusa. The most closely related species to ACPtTwasSporomusa malonicawith an average amino acid identity of 80.1%. The genome of ACPtTencoded cytochromes, ubiquinones, the Wood-Ljungdahl gene cluster and an Rnf complex, which were identified as common features allSporomusatype strains. However, strain ACPt did not ferment H2+ CO2via acetogenesis as otherSporomusaspecies, but employed the metabolism of a carboxydotrophic hydrogenogen converting CO to H2+ CO2. Based on the genomic, morphological and physiological features presented in this study, strain ACPtTis proposed as a novel species in the genusSporomusawith the nameSporomusa carbonissp. nov. (DSM 116159Tand CCOS 2105T).