title: Endothiovibrio diazotrophicus gen. nov., sp. nov., a novel nitrogen-fixing, sulfur-oxidizing gammaproteobacterium isolated from a salt marsh.
abstract: A novel non-phototrophic, marine, sulfur-oxidizing bacterium, strain S-1T, was isolated from a coastal salt marsh in Massachusetts, USA. Cells are Gram-stain-negative vibrios motile by means of a single polar unsheathed flagellum. S-1T is an obligate microaerophile with limited metabolic capacity. It grows chemolithoautotrophically utilizing sulfide and thiosulfate as electron donors, converting these compounds to sulfate, and the Calvin-Benson-Bassham cycle for carbon fixation. Cells of S-1T did not grow on any of a large number of organic carbon sources and there was no evidence for chemoorganoheterotrophic growth. Cells produced internal sulfur globules during growth on sulfide and thiosulfate. S-1T is strongly diazotrophic, as demonstrated by 15N2 fixation and acetylene reduction activity by cells when a fixed nitrogen source is absent from the growth medium. The marine nature of this organism is evident from its ability to grow in 10 to 100 % artificial seawater but not at lower concentrations and NaCl alone cannot substitute for sea salts. The major cellular fatty acids are C16 : 1ω7c, C16 : 0, and C18 : 1ω7c. Phosphatidylethanolamine and phosphatidylglycerol are the major polar lipids. Q8 is the only respiratory quinone. S-1T genomic DNA has a G+C content of 67.6 mol%. Based on its 16S rRNA gene sequence, S-1T shows the closest phylogenetic relationship to non-phototrophic species within the family Thioalkalispiraceae of the class Gammaproteobacteria. The name Endothiovibrio diazotrophicus is proposed for this organism, with S-1T as the type strain (ATCC BAA-1439T=JCM 17961T).
authors.affiliation: School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, Nevada 89154-4004, USA.
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Bazylinski
authors.affiliation: School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, Nevada 89154-4004, USA.
authors.forename: Viviana
authors.initials: V
authors.lastname: Morillo
authors.affiliation: CEA Cadarache/CNRS/Université Aix-Marseille, UMR7265 Biosciences and Biotechnologies Institute, Laboratoire de Bioénergétique Cellulaire, Saint Paul lez Durance 13108, France.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Lefèvre
authors.affiliation: School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, Nevada 89154-4004, USA.
authors.forename: Nathan
authors.initials: N
authors.lastname: Viloria
authors.affiliation: Novozymes North America Inc., 9000 Development Drive, Morrisville, North Carolina 27560, USA.
authors.forename: Bradley L
authors.initials: BL
authors.lastname: Dubbels
authors.affiliation: School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney NSW 2052, Australia.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Williams
mesh_terms: D015373:Bacterial Typing Techniques; D001482:Base Composition; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry; D020563:Gammaproteobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D008404:Massachusetts; D009584:Nitrogen / Q000378:metabolism; D009586:Nitrogen Fixation; D010743:Phospholipids / Q000737:chemistry; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013455:Sulfur / Q000378:metabolism; D014871:Water Microbiology; D053833:Wetlands
chemical_list: D004269:DNA, Bacterial; D005227:Fatty Acids; D010743:Phospholipids; D012336:RNA, Ribosomal, 16S; D013455:Sulfur; D009584:Nitrogen