Cellulomonas aurantiaca Kim et al. 2020 is a later heterotypic synonym of Cellulomonas algicola Yamamura et al. 2019.

Cellulomonas algicola KZ-21T was compared with Cellulomonas aurantiaca THG-SMD2.3T to examine the taxonomic relationship between the two type strains. The 16S rRNA gene sequence of Cellulomonas algicola KZ-21T shared complete similarity (100.0 %) with that of Cellulomonas aurantiaca THG-SMD2.3T. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the two strains formed a tight cluster within the genus Cellulomonas. Genome comparison between the two strains revealed an average nucleotide identity of 99.2 % and a digital DNA-DNA hybridization estimate of 93.7±1.8 %, strongly indicating that the two strains belong to a single species. In addition, neither strain displayed any striking differences in metabolic, physiological or chemotaxonomic features. Therefore, we propose Cellulomonas aurantiaca as a later heterotypic synonym of Cellulomonas algicola.

Cellulomonas aurantiaca sp. nov., isolated from a soil sample from a tangerine field.

A Gram-stain positive, facultatively aerobic, motile and rod-shaped bacterial strain, designated THG-SMD2.3T, was isolated from a soil sample collected in a tangerine field, Republic of Korea. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Cellulomonas and to be closely related to Cellulomonas fimi ATCC 484T (98.5%), Cellulomonas biazotea DSM 20112T (98.3%), Cellulomonas chitinilytica X.bu-bT (98.0%), Cellulomonas xylanilytica XIL11T (97.2%), Cellulomonas humilata ATCC 25174T (97.1%) and Cellulomonas composti TR7-06T (97.0%). The 16S rRNA gene sequence similarities with other current species of the genus Cellulomonas were in the range 95.4-96.6%. Catalase and oxidase tests were found to be positive. The DNA G+C content was determined to be 73.0 mol%. DNA-DNA hybridization values between strain THG-SMD2.3T and C. fimi ATCC 484T, C. biazotea DSM 20112T, C. chitinilytica X.bu-bT, C. xylanilytica XIL11T, C. humilata ATCC 25174T and C. composti TR7-06T were 58.1 ± 1.6%, 56.7 ± 0.8%, 30.3 ± 1.6%, 22.8 ± 1.6%, 19.9 ± 1.6%, and 13.5 ± 3.0%, respectively. Strain THG-SMD2.3T was also found to be able to grow at 20-42 °C, at 0-3% NaCl and at pH 5.5-10. The major fatty acids were identified as anteiso-C15:0, iso-C15:0, anteiso-C17:0 and iso-C14:0. The predominant menaquinone was identified as tetrahydrogenated menaquinones with nine isoprene units [MK-9(H4)]. The polar lipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids and two unidentified phospholipids. Based on these phenotypic, genotypic and phylogenetic characterisations strain THG-SMD2.3T (= KACC 19341T = CGMCC 1.16303T) is concluded to represent a novel species of the genus Cellulomonas, for which the name Cellulomonas aurantiaca sp. nov. is proposed.