title: Dethiosulfatibacter aminovorans gen. nov., sp. nov., a novel thiosulfate-reducing bacterium isolated from coastal marine sediment via sulfate-reducing enrichment with Casamino acids.
abstract: A sulfate-reducing enrichment culture originating from coastal marine sediment of the eutrophic Tokyo Bay, Japan, was successfully established with Casamino acids as a substrate. A thiosulfate reducer, strain C/G2(T), was isolated from the enrichment culture after further enrichment with glutamate. Cells of strain C/G2(T) were non-motile rods (0.6-0.8 microm x 2.2-4.8 microm) and were found singly or in pairs and sometimes in short chains. Spores were not formed. Cells of strain C/G2(T) stained Gram-negatively, despite possessing Gram-positive cell walls. The optimum temperature for growth was 28-30 degrees C, the optimum pH was around 7.8 and the optimum salt concentration was 20-30 g l(-1). Lactate, pyruvate, serine, cysteine, threonine, glutamate, histidine, lysine, arginine, Casamino acids, peptone and yeast extract were fermented as single substrates and no sugar was used as a fermentative substrate. A Stickland reaction was observed with some pairs of amino acids. Fumarate, alanine, proline, phenylalanine, tryptophan, glutamine and aspartate were utilized only in the presence of thiosulfate. Strain C/G2(T) fermented glutamate to H2, CO2, acetate and propionate. Thiosulfate and elemental sulfur were reduced to sulfide. Sulfate, sulfite and nitrate were not utilized as electron acceptors. The growth of strain C/G2(T) on Casamino acids or glutamate was enhanced by co-culturing with Desulfovibrio sp. isolated from the original mixed culture enriched with Casamino acids. The DNA G+C content of strain C/G2(T) was 41.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain C/G2(T) formed a distinct cluster with species of the genus Sedimentibacter. The closest relative was Sedimentibacter hydroxybenzoicus (with a gene sequence similarity of 91 %). On the basis of its phylogenetic and phenotypic properties, strain C/G2(T) (=JCM 13356(T)=NBRC 101112(T)=DSM 17477(T)) is proposed as representing a new genus and novel species, Dethiosulfatibacter aminovorans gen. nov., sp. nov.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Minamiohsawa 1-1, Hachioji 192-0397, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Takii
authors.affiliation: Research Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba Central 6, Tsukuba 305-8566, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hanada
authors.affiliation: Research Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba Central 6, Tsukuba 305-8566, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Tamaki
authors.affiliation: Research Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba Central 6, Tsukuba 305-8566, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Ueno
authors.affiliation: Research Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba Central 6, Tsukuba 305-8566, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Sekiguchi
authors.affiliation: Tokyo Metropolitan Institute of Public Health, Hyakunin-cho 3-24-1, Shinjuku-ku, Tokyo 163-0073, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ibe
authors.affiliation: Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Minamiohsawa 1-1, Hachioji 192-0397, Japan.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Matsuura
mesh_terms: D015373:Bacterial Typing Techniques; D001431:Bacteriological Techniques / Q000379:methods*; D001482:Base Composition; D002244:Carbon / Q000378:metabolism; D002704:Chlorates / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005285:Fermentation / Q000502:physiology; D020459:Genes, rRNA; D019015:Geologic Sediments / Q000382:microbiology*; D018698:Glutamic Acid / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000145:classification* / Q000166:cytology / Q000302:isolation & purification* / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D007564:Japan; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013696:Temperature; D013885:Thiosulfates / Q000378:metabolism*
chemical_list: D002704:Chlorates; D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D013885:Thiosulfates; D018698:Glutamic Acid; D002244:Carbon; D009584:Nitrogen; C032706:sodium chlorate