Actinomadura graeca sp. nov.: A novel producer of the macrocyclic antibiotic zelkovamycin

PLoS One. 2021 Nov 30;16(11):e0260413. doi: 10.1371/journal.pone.0260413. eCollection 2021.

Abstract

As part of a screening programme for antibiotic-producing bacteria, a novel Actinomadura species was discovered from a soil sample collected in Santorini, Greece. Preliminary 16S rRNA gene sequence comparisons highlighted Actinomadura macra as the most similar characterised species. However, whole-genome sequencing revealed an average nucleotide identity (ANI) value of 89% with A. macra, the highest among related species. Further phenotypic and chemotaxonomic analyses confirmed that the isolate represents a previously uncharacterised species in the genus Actinomadura, for which the name Actinomadura graeca sp. nov. is proposed (type strain 32-07T). The G+C content of A. graeca 32-07 is 72.36%. The cell wall contains DL-diaminopimelic acid, intracellular sugars are glucose, ribose and galactose, the predominant menaquinone is MK-9(H6), the major cellular lipid is phosphatidylinositol and fatty acids consist mainly of hexadecanoic acid. No mycolic acid was detected. Furthermore, A. graeca 32-07 has been confirmed as a novel producer of the non-ribosomal peptide antibiotic zelkovamycin and we report herein a provisional description of the unique biosynthetic gene cluster.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinomadura* / classification
  • Actinomadura* / genetics
  • Actinomadura* / metabolism
  • Actinomadura* / ultrastructure
  • Antimicrobial Cationic Peptides* / biosynthesis
  • Antimicrobial Cationic Peptides* / genetics
  • Base Composition*
  • Macrocyclic Compounds / metabolism*

Substances

  • Antimicrobial Cationic Peptides
  • Macrocyclic Compounds
  • zelkovamycin