RESUMO
We carried out a polyphasic taxonomic study on a new halophilic strain designated 3(2)T, isolated from Meighan wetland, Iran. Cells of the novel strain were Gram-stain-negative, non-hemolytic, catalase- and oxidase-positive, rod-shaped, non-endospore-forming and motile. Cell growth occurred at 3-15â% NaCl (w/v; optimum, 5â%), pH 7.0-9.0 (optimum, pH 7.5-8.0) and 15-35 °C (optimum, 30 °C). 16S rRNA gene sequence comparisons confirmed the affiliation of strain 3(2)T to the class Gammaproteobacteria and the genus Halomonas with highest similarity to Halomonas daqiaonensis YCSA28T (98.4â%) and Halomonas ventosae Al12T (97.9â%). Experimental and in silico DNA-DNA hybridization values were 42.7 and 35.1% with H. daqiaonensis IBRC-M 10931T and 48 and 35.2% with H. ventosae IBRC-M 10566T, respectively, and indicated that they are different members of the same genus. The genome of the type strain was characterized by a size of 3.83 Mbp with 63 scaffolds and a G+C content of 64.8 mol%. Moreover, the average nucleotide identity values against H. ventosae Al12T and H. daqiaonensis YCSA28T were 88.8 and 88.5â%, respectively. The predominant respiratory quinone was Q-9 (92â%) with Q-8 (8â%) as a minor component. Major fatty acids were C16â:â0 cyclo, C19â:â0 ω8c, C16â:â1 ω7c and/or iso-C15:0 2-OH, C12â:â0 3-OH and C18â:â1 ω7c. The polar lipid profile of the strain contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphoaminoglycolipid and four unidentified phospholipids. According to our results, strain 3(2)T could be classified as a novel species in the genus Halomonas for which the name Halomonas lysinitropha sp. nov. is proposed. The type strain is 3(2)T (=IBRC M 10929T=LMG 29450T=CIP 111708T).
Assuntos
Halomonas/classificação , Filogenia , Águas Salinas , Áreas Alagadas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Halomonas/isolamento & purificação , Irã (Geográfico) , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
A novel strain, designated as MX6T was isolated from Meighan wetland, in the centre of Iran. The cells were Gram-stain-positive, motile, coccoid to rod-shaped, oxidase- and catalase-positive. The strain grew optimally at 35 °C, 3â% (w/v) NaCl and pH 7-7.5. A polyphasic taxonomic study was undertaken in order to characterize the strain in detail. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that MX6T represented a member of the phylum Firmicutes, family Planococcaceae, genus Planomicrobium, and showed the highest similarity with Planomicrobium flavidum ISL-41T (98.2â%) and Planomicrobium psychrophilum CMC 53orT (98.0â%). The main polar lipids of MX6T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and seven unidentified phospholipids and its DNA G+C content was 45.5 mol%. Major cellular fatty acids were anteiso-C15â:â0, C16â:â1ω7c alcohol, iso-C14â:â0, iso-C15â:â0 and iso-C16â:â0 and the predominant respiratory quinone was Q-8 (62â%). Experimental DNA-DNA hybridization between MX6T and Planomicrobium flavidum IBRC-M 11047T was 20â%, supporting the differential taxonomic status of MX6T as representing a different taxon. All these data indicate that MX6T represents a novel species of the genus Planomicrobium, for which the name Planomicrobium iranicum sp. nov. is proposed. The type strain is MX6T (=IBRC M 10928T=LMG 28548T).