Description of Anaerotignum aminivorans gen. nov., sp. nov., a strictly anaerobic, amino-acid-decomposing bacterium isolated from a methanogenic reactor, and reclassification of Clostridium propionicum, Clostridium neopropionicum and Clostridium lactatifermentans as species of the genus Anaerotignum

Abstract

A strictly anaerobic bacterial strain (SH021) was isolated from a methanogenic reactor. Cells were Gram-stain-positive, motile, straight or slightly curved rods. The optimum temperature for growth was 35 °C, and the optimum pH was 6.1-7.7. The strain was asaccharolytic and utilized amino acids as growth substrates. The strain produced acetate and propionate from l-alanine and l-serine, and propionate and butyrate from l-threonine. Branched-chain amino acids (l-isoleucine, l-leucine and l-valine) were utilized weakly, and isovalerate or isobutyrate was produced. Strain SH021 utilized pyruvate and lactate, and converted them to acetate and propionate. The genomic DNA G+C content was 38.2 mol%. Compounds related to iso-C15 : 0 were detected as major components in the cellular fatty acids analysis. The diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid. On the basis of 16S rRNA gene sequences, the most closely related known species were Clostridium propionicum, Clostridium neopropionicum and Clostridium lactatifermentans in cluster XIVb of the class Clostridia. Based on the phylogenetic and phenotypic data, Anaerotignum aminivorans gen. nov., sp. nov. is proposed to accommodate strain SH021 (=JCM 31556=DSM 103575). For the three related species of the genus Clostridium, Anaerotignum propionicum comb. nov. (type strain DSM 1682=JCM 1430=ATCC 25522=CCUG 9280=NCIMB 10656=VPI 5303), Anaerotignum neopropionicum comb. nov. (type strain X4=DSM 3847=KCTC 15564) and Anaerotignum lactatifermentans comb. nov. (type strain G17=DSM 14214=LMG 20954) are proposed with emended descriptions of these species.

Constraints in Anaerobic Microbial Dechlorination, Fermentation, and Sulfate-Reduction Induced by High Concentrations of Tetrachloroethylene

“…5) in this study was similar to Anaerotignum propionicum JCM1430 (Collins et al 1994;Ueki et al 2017) and Anaerotignum neopropionicum DSM3847 (Ueki et al 2017) with 100.0% identicality. The strains JCM1430 and DSM3847 are gram-positive and spore-forming bacteria, which ferment lactate to acetate and propionate (Tholozan et al 1992;Ueki et al 2017). It is reasonable that Anaerotignum was one of the fermenters in this study.…”

High-Throughput, Sequence-Based Analysis of the Microbiota of Greek Kefir Grains from Two Geographic Regions

“…At the species level, only rare sequences of C. orbiscindens (0.003 and 0.005%) and C. lactatifermentans (0.002 and 0.001%) were noted. C. orbiscindens is an abundant member of the human gut microbiome ( 41 ), whereas C. lactatifermentans is a member of the clostridial 16S rRNA cluster XIVb, originally described as a chicken caecum isolate ( 42 ) and was recently proposed to be re-classified in the novel genus Anaerotignum ( 43 ). Sequences belonging to the Clostridiaceae family have previously been reported from only one study in kefir ( 7 ).…”

Enrichment of Anaerobic Syngas-Converting Communities and Isolation of a Novel Carboxydotrophic Acetobacterium wieringae Strain JM

“…Microorganisms closely related to A. neopropionicum (2% of total sequences) and P. propionicus (1% of total sequences) were present in the enrichment cultures JM(16) ( Table 1), and were likely responsible for propionate production (Figures 1B,C). A. neopropionicum and P. propionicus are known for their capability to convert ethanol to propionate (Schink et al, 1987; Tholozan et al, 1992;Ueki et al, 2017). These results suggest that a synergistic interaction between Acetobacterium species and propionate-forming bacteria was taking place in the enrichments, where Acetobacterium is consuming CO to produce acetate and ethanol, and ethanol further used by close relatives to A. neopropionicum and P. propionicus to form propionate.…”