Magnetospirillum sulfuroxidans sp. nov., capable of sulfur-dependent lithoautotrophy and a taxonomic reevaluation of the order Rhodospirillales

Oleispirillum naphthae gen. nov., sp. nov., a bacterium isolated from oil sludge, and proposal of Oleispirillaceae fam. nov.

“…Percentages of conserved proteins (POCP) between two microbial genomes were calculated according to the method described previously [39]. The AAI values between strain Y-M2 T and the genera of ‘ Magnetospirillaceae ’, ‘ Novispirillaceae ’, and Rhodospirillaceae were ≤60.2 % (Table S2), close to the family delineating threshold (60.0 %) of the order Rhodospirillales [15], supporting the proposal of a novel family. ANI and POCP values were less than 71.8 and 48.0 %, respectively (Table S2).…”

“…Gram-stain and spore-stain kits (Solarbio) were used to assess Gram staining and spore formation, respectively. Growth of strain Y-M2 T at different temperatures (15,20,25,30, and 37 °C), pH values (pH 5.5-8.0 at intervals of 0.5 pH units), and NaCl concentrations (0-70 g l −1 at intervals of 10 g l −1 NaCl) was determined in R2A broth by measuring the OD 600 value with a spectrometer (DU730, Beckman Coulter). The following sterilized anoxic buffers at a final concentration of 20 mM were added into the fresh medium: MES (pH 5.5, 6.0, 6.5), PIPES (pH 7.0, 7.5), Tris (pH 8.0).…”

“…However, six more novel families were separated from the existing families within this order according to the phylogenomic analyses [15]. The family Rhodospirillaceae was split into family 'Dongiaceae' (including genera Dongia, Aliidongia, and Hypericibacter), 'Oceanibaculaceae' (Oceanibaculum), and current Rhodospirillaceae (Pararhodospirillum, Phaeovibrio, Rhodospira, Rhodospirillum and Roseospirillum) [15]. Most members of this order are chemoorganoheterotrophic and/ or photoorganoheterotrophic [16][17][18].…”

The Genome of <em>Varunaivibrio sulfuroxidans</em> Strain TC8^T, a Metabolically Versatile Alphaproteobacterium from the Tor Caldara Gas Vents in the Tyrrhenian Sea

“…Consistent with these observations, Alphaproteobacteria were relatively abundant at Tor Caldara (4.5 to 15.1 % of the vent-associated sediment microbial community and 6 to 10 % of the substrate-attached biofilms) [1,10], and a novel genus of sulfur-oxidizing, chemolithoautotrophic alphaproteobacterium, Varunaivibrio sulfuroxidans strain TC8 T , was isolated and characterized from the sediments associated with the gas vents of this site [15]. Currently, V. sulfuroxidans belongs to the family Thalassospiraceae (although a recent study proposed its reassignment to the new family Magnetovibrionaceae) [16], which includes four genera of marine bacteria: Magnetospira, Magnetovibrio, Thalassospira and Varunaivibrio [17]. In particular, Magnetospira thiophila, Magnetovibrio blakemorei and Varunaivibrio sulfuroxidans are facultative chemilthoautotrophs that conserve energy by anaerobic (nitrate) and/or microaerobic respiration, with reduced sulfur species as electron donors [15,18,19].…”

Description of Oleispirillum naphthae gen. nov., sp. nov., a potential nitrogen-fixing bacterium of the order Rhodospirillales, and proposal of Oleispirillaceae fam. nov.

“…However, six more novel families were separated from the existing families within this order according to the phylogenomic analyses (ref). The family Rhodospirillaceae was splitted into family "Dongiaceae" (Dongia, Aliidongia, and Hypericibacter), "Oceanibaculaceae" (Oceanibaculum), and current Rhodospirillaceae (Pararhodospirillum, Phaeovibrio, Rhodospira, Rhodospirillum and Roseospirillum) (Koziaeva et al, 2023). Most members of this order are chemoorganoheterotrophic and/or photoorganoheterotrophic (Guyoneaud et al, 2002, Kalyan Chakravarthy et al, 2007, Urdiain et al, 2008.…”