Microvirga terricola sp. nov. and Microvirga solisilvae sp. nov, isolated from forest soil

Two Gram-staining-negative, aerobic and rod-shaped strains, designated c23x22(T) and sex2(T), were isolated from forest soil collected from Chebaling National Nature Reserve in Guangdong Province and Limu Mountain National Forest Park in Hainan Province, P. R. China, respectively. Phylogenetic analyses based on 16S rRNA gene sequences revealed that they belonged to the genus Microvirga, and strain c23 x22(T) was most closely related to 'Microvirga alba' KCTC 72385, while strain sex2(T) showed close relationship with Microvirga guangxiensis CGMCC 1.7666(T). The average nucleotide identity and digital DNA-DNA hybridization values between strains c23 x22(T) and sex2(T) and their close relatives, 'M. alba' KCTC 72385 and M. guangxiensis CGMCC 1.7666(T), were all below the threshold values for species delimitation. The predominant quinones of the two novel strains were ubiquinone 10, and the major fatty acids contained C-19:0 cyclo omega 8c and summed feature 8 (C-18:1 omega 7c and/or C-18:1 omega 6c). Their predominant polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The phenotypic, genotypic and chemotaxonomic analyses clearly supported that strains c23 x 22(T) and sex2(T) represent two novel species of the genus Microvirga, for which the name Microvirga terricola sp. nov. (type strain c23 x 22(T) = GDMCC 1.1700(T) = KCTC 62432(T)) and Microvirga solisilvae sp. nov. (type strain sex2(T) = GDMCC 1.1651(T) = KACC 21311(T)) are proposed, respectively.

Automated summary

Two novel species of the genus Microvirga, Microvirga terricola sp. nov. (type strain c23 x 22(T) = GDMCC 1.1700(T) = KCTC 62432(T)) and Microvirga solisilvae sp. nov. (type strain sex2(T) = GDMCC 1.1651(T) = KACC 21311(T)), were isolated from forest soil in Guangdong Province and Hainan Province, China, respectively. They showed distinct morphological, genetic, and chemotaxonomic characteristics, and phylogenetic analysis supported their placement within the genus Microvirga.