Herbidospora solisilvae sp. nov., a novel cellulose-degrading actinobacterium isolated from forest soil

Antonie Van Leeuwenhoek. 2021 May;114(5):581-590. doi: 10.1007/s10482-021-01542-6. Epub 2021 Mar 1.

Abstract

An aerobic, non-motile, Gram-stain positive, cellulose-degrading actinobacterium, designated strain NEAU-GS84T, was isolated from a forest soil sample collected from Linchun Ridge Forest Park in Sanya, Hainan Province, China, and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics indicated that strain NEAU-GS84T could belong to the genus Herbidospora. The 16S rRNA gene sequence analysis indeed confirmed that strain NEAU-GS84T belonged to the genus Herbidospora and was most closely related to Herbidospora yilanensis JCM 18062T (99.2% 16S rRNA gene sequence similarity) and Herbidospora galbida NEAU-GS14T (99.0%). The cell wall of strain NEAU-GS84T contained meso-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates mainly contained glucose, madurose and ribose. The major polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, hydroxyphosphatidylethanolamin, phosphoglycolipids, two phosphatidylinositol mannosides and one unidentified phospholipid. The predominant menaquinone was MK-10(H4). Major fatty acids were 10-methly C17:0, C17:0 and iso-C16:0. These chemotaxonomic data substantiated the affiliation of strain NEAU-GS84T to the genus Herbidospora. The DNA G+C content was 70.7 mol%. The genome size of strain NEAU-GS84T is about 8.37 Mb and contained 41 cellulose-binding domain synthesis genes, 13 β-glucosidase synthesis genes, 6 endoglucanase synthesis genes and 9 xylanase synthesis genes. Based on digital DNA-DNA hybridization and average nucleotide identity values, the new strain NEAU-GS84T could be differentiated from its closest relatives. Therefore, the strain represents a novel species of the genus Herbidospora, for which the name Herbidospora solisilvae sp. nov. is proposed. The type strain is NEAU-GS84T (= CCTCC AA 2018041T = JCM 33460T).

Keywords: 16S rRNA gene; Forest soil; Herbidospora solisilvae sp. nov.; Polyphasic taxonomy.

MeSH terms

  • Actinobacteria
  • Bacterial Typing Techniques
  • Cellulose*
  • DNA, Bacterial / genetics
  • Fatty Acids
  • Forests
  • Phospholipids
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA
  • Soil Microbiology
  • Soil*
  • Vitamin K 2

Substances

  • DNA, Bacterial
  • Fatty Acids
  • Phospholipids
  • RNA, Ribosomal, 16S
  • Soil
  • Vitamin K 2
  • Cellulose

Supplementary concepts

  • Herbidospora yilanensis