title: Methylophaga nitratireducenticrescens sp. nov. and Methylophaga frappieri sp. nov., isolated from the biofilm of the methanol-fed denitrification system treating the seawater at the Montreal Biodome.
abstract: Two bacterial strains, designated JAM1(T) and JAM7(T), were isolated from a methanol-fed denitrification system treating seawater at the Montreal Biodome, Canada. They were affiliated within the genus Methylophaga of the Gammaproteobacteria by analysis of the 16S rRNA gene sequences. Strain JAM1(T) had the capacity to grow under denitrifying conditions by reducing nitrate into nitrite which is unique among the species of the genus Methylophaga. Major fatty acids were C16:1ω7c or ω6c, C16:0 and C18:1ω7c or ω6c. The major ubiquinone was Q8. Both strains required vitamin B12 and Na(+) ions for growth. The genomes of strains JAM1(T) and JAM7(T) have been completely sequenced and showed a DNA G+C content of 44.7 mol% and 47.8 mol%, respectively. Growth occurred at pH 6-11 and at 0.5-8% NaCl. Both genomes contained predicted ORFs encoding the key enzymes of the ribulose monophosphate pathway. Also, operons encoding two nitrate reductases (Nar), two nitric oxide reductases (Nor), one nitrous oxide reductase (Nos) and one truncated nitrite reductase (NirK) were clustered in a 67 kb chromosomal region in strain JAM1(T). No such operons were found in strain JAM7(T). These results supported the affiliation of the two strains as novel species within the genus Methylophaga. The names Methylophaga nitratireducenticrescens sp. nov. for type strain JAM1(T) (=DSM 25689(T)=ATCC BAA-2433(T)) and Methylophaga frappieri sp. nov. for type strain JAM7(T) (=DSM 25690(T)=ATCC BAA-2434(T)) are proposed.
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Céline
authors.initials: C
authors.lastname: Villeneuve
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Christine
authors.initials: C
authors.lastname: Martineau
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Florian
authors.initials: F
authors.lastname: Mauffrey
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Richard
authors.initials: R
authors.lastname: Villemur
mesh_terms: D015373:Bacterial Typing Techniques; D001482:Base Composition; D018441:Biofilms; D002170:Canada; D004269:DNA, Bacterial / Q000235:genetics; D058440:Denitrification; D005227:Fatty Acids / Q000032:analysis; D000432:Methanol / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism; D010802:Phylogeny; D044147:Piscirickettsiaceae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D014451:Ubiquinone / Q000032:analysis; D018508:Water Purification
chemical_list: D004269:DNA, Bacterial; D005227:Fatty Acids; D009566:Nitrates; D012336:RNA, Ribosomal, 16S; D014451:Ubiquinone; C030778:ubiquinone 8; D000432:Methanol