Thermomonas flagellata sp. nov. and Thermomonas alba sp. nov., two novel members of the phylum Pseudomonadota isolated from hot spring sediments

Abstract

Two novel species, designated strains SYSU G04041T and SYSU G04536T, were isolated from hot spring sediments collected in Yunnan, PR China. Phenotypic and chemotaxonomic analyses, and whole-genome sequencing were used to determine the taxonomic positions of the candidate strains. Phylogenetic analysis using 16S rRNA gene sequence indicated that strain SYSU G04041T showed the highest sequence similarity to Thermomonas haemolytica A50-7-3T (97.5 %), and SYSU G04536T showed the highest sequence similarity to Thermomonas hydrothermalis SGM-6T (98.2 %). The strains could be differentiated from other species of the genus Thermomonas by their distinct phenotypic and genotypic characteristics. Cells of strains SYSU G04041T and SYSU G04536T were aerobic, motile and Gram-stain-negative. Growth both occurred optimally at 45 °C and pH 7.0 for SYSU G04041T and SYSU G04536T. In addition, the predominant respiratory quinone in both isolates was ubiquinone Q-8. The major fatty acids (>10 %) of strain SYSU G04041T were C16 : 0, iso-C15 : 0 and iso-C16 : 0, while the major fatty acids (>10 %) of strain SYSU G04536T were iso-C15 : 0 and iso-C16 : 0. The main detected polar lipids in strains SYSU G04041T and SYSU G04536T included phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The G+C contents of the genomic DNA of strains SYSU G04041T and SYSU G04536T based on draft genomic sequences were 72.5 and 68.3 %, respectively. On the basis of phenotypic, genotypic and phylogenetic data, strains SYSU G04041T and SYSU G04536T represent two novel species of the genus Thermomonas , for which the names Thermomonas flagellata sp. nov. and Thermomonas alba sp. nov. are proposed, with the type strains SYSU G04041T (=CGMCC 1.19366T=KCTC 92228T) and SYSU G04536T (=CGMCC 1.19367T=KCTC 82839T), respectively.

Thermomonas paludicola sp. nov., isolated from a lotus wetland

“… *Data from Guo et al [24]. Grown on R2A at 30 °C †Data from Liu et al [25]. Grown in R2A at 45 °C ‡Summed features are fatty acids that cannot be resolved reliably from another fatty acid using the chromatographic conditions chosen.…”

“…According to phenotypic comparison, IMCC34681 T and three species of the genus Thermomonas (T. brevis KACC16975 T , T. fusca KACC16976 T and T. koreensis KACC11483 T ) showed similar phenotypic characteristics in the growth range for temperature, pH *Data from Guo et al [24]. Grown on R2A at 30 °C †Data from Liu et al [25]. Grown in R2A at 45 °C ‡Summed features are fatty acids that cannot be resolved reliably from another fatty acid using the chromatographic conditions chosen.…”

“… ||Data from Guo et al [24]. ¶Data from Liu et al [25]. #All species contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as major polar lipids.…”

“…flagellata and T. alba [25] were validly published very recently in 2022. The etymology of the genus Thermomonas refers to a thermophilic monad, which was based on the thermophilic growth of T.…”

“…Among the genera of the family Lysobacteraceae, the genus Thermomonas was firstly described by Busse et al [13] on the basis of the results of taxonomic analysis of four strains growing at high temperatures isolated from kaolin slurry. As of July 2022, the genus comprises 10 species with validly published names (https://lpsn.dsmz.de/genus/thermomonas) [18]: T. haemolytica [13], T. brevis [19], T. fusca [19], T. hydrothermalis [20], T. koreensis [21], T. carbonis [22], T. aquatica [23], T. beijingensis [24], T. flagellata [25] and T. alba [25]. Among the species of the genus Thermomonas, the names of T. beijingensis, T. flagellata and T. alba [25] were validly published very recently in 2022.…”