Saccharothrix camelliae sp. nov., isolated from rhizosphere soil of Camellia oleifera Abel and proposal of Saccharothrixyanglingensis as a later heterotypic synonym of Saccharothrix longispora

TL;DR

A new species of bacteria, Saccharothrix camelliae, was discovered in soil near a plant in China and found to be distinct from related species.

Contribution

The discovery of a new Saccharothrix species and the reclassification of Saccharothrixyanglingensis as a synonym of Saccharothrix longispora.

Findings

Strain HUAS TT1T is a novel species in the genus Saccharothrix, named Saccharothrix camelliae.

Saccharothrixyanglingensis is proposed as a later heterotypic synonym of Saccharothrix longispora.

Genomic and phylogenetic analyses confirmed the distinctness of HUAS TT1T from other Saccharothrix species.

Abstract

A novel actinobacterial strain, designated HUAS TT1T, was isolated from the rhizosphere soil of Camellia oleifera collected from Changde City, Hunan Province, China. Sequence analysis of the full-length 16S rRNA gene revealed that strain HUAS TT1T belonged to the genus Saccharothrix and shared the highest sequence similarities with Saccharothrix yanglingensis Hhs.015T (99.30%), Saccharothrix carnea NEAU-yn17T (98.89%), Saccharothrix hoggarensis SA181T (98.89%), Saccharothrix saharensis SA152T (98.82%), and Saccharothrix longispora NRRL B-16116T (98.75%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HUAS TT1T was related to Saccharothrix yanglingensis Hhs.015T and Saccharothrix longispora NRRL B-16116T. Phylogenetic analysis based on whole-genome sequences and 120 core gene sequences showed that the evolutionary neighbors of strain HUAS TT1T were Saccharothrix hoggarensis SA181T and Saccharothrix saharensis SA152T. However, the ANIb/m and dDDH values between the whole-genome sequences of strain HUAS TT1T and Saccharothrix hoggarensis SA181T/Saccharothrix saharensis SA152T were 85.82%/88.80 and 32.90%, 86.42%/89.43, and 34.40%, respectively, well below the 95–96 and 70% cut-off points recommended for delineating species, suggesting that strain HUAS TT1T is a novel Saccharothrix species. This result was further verified by the phenotypic and chemotaxonomic differences between them. Therefore, according to the above data, strain HUAS TT1T represents a novel species of the genus Saccharothrix, for which the name Saccharothrix camelliae sp. nov. is proposed. The type strain used was HUAS TT1T (=MCCC 1K09364T = JCM 37292T). In addition, the phenotypic, chemotaxonomic, and genotypic characteristics, as well as the phylogenetic information, indicated that S. yanglingensis CGMCC 4.5627T and S. longispora CGMCC 4.1357T belong to the same species. Therefore, on the basis of these results and Rule 42 of the Bacteriological Code, we propose that Saccharothrix yanglingensis is a later heterotypic synonym of Saccharothrix longispora, for which an emended description is given.

Figures