Trinickia mobilis sp. nov. and Trinickia acidisoli sp. nov., isolated from soil

Abstract

Two novel Gram-stain-negative, aerobic and rod-shaped bacterial strains, designated DHG64^T and 4D114^T, were isolated from forest soil of Dinghushan Biosphere Reserve, Guangdong Province, PR China. DHG64^T grew at 12-37 °C (optimum 33 °C), pH 4.5-10.0 (optimum 6.5-7.5) and in the presence of 0-2.0 % NaCl (w/v); while 4D114^T grew at 12-37 °C (optimum 20-33 °C), pH 4.0-7.0 (optimum 4.5-6.0) and in the presence of 0-1.0 % NaCl (w/v). DHG64^T and 4D114^T showed 97.1-98.0 and 97.5-98.4 % 16S rRNA gene sequence similarities with seven species of the genus Trinickia with validly published names, respectively. In the phylogenetic trees based on 16S rRNA gene and genome sequences, both strains formed a clade with the members of genus Trinickia but well separated from each other. The average nucleotide identity and digital DNA-DNA hybridisation values for the novel strains to all species of the genus Trinickia with validly published names were in the ranges of 80.6-85.0 and 22.4-28.0 %, respectively. DHG64^T contained C_{16 : 0}, C_{17 : 0} cyclo and C_{19 : 0} cyclo ω8c, while 4D114^T had C_{16 : 0}, C_{17 : 0} cyclo, C_{19 : 0} cyclo ω8c and summed feature 2 (iso-C_{16 : 1} I and/or C_{14 : 0} 3-OH) as the major cellular fatty acids. The major polar lipids for strains DHG64^T and 4D114^T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C contents of DHG64^T and 4D114^T were 63.0 and 62.8 mol%, respectively. Genomic analyses indicated that DHG64^T and 4D114^T may have potential for various applications, such as developing drugs against certain health problems and restoring environments polluted with metal ions and/or benzoate. On the basis of the results of morphological, physiological, biochemical and phylogenetic analyses, strains DHG64^T and 4D114^T were classified as representing two novel species of the genus Trinickia, for which the names Trinickia mobilis sp. nov. (type strain DHG64^T = KACC 21223^T = GDMCC 1.1282^T) and Trinickia acidisoli sp. nov. (type strain 4D114^T = KCTC 82876^T = GDMCC 1.2131^T) are proposed.

Keywords: Phylogeny; Taxonomy; Trinickia; Trinickia acidisoli; Trinickia mobilis.