Peterkaempfera podocarpi sp. nov., a novel actinobacterium isolated from rhizosphere soil of Podocarpus rumphii in Sumba Island, Indonesia

A novel actinobacterial strain, designated as SMS 1(5)a T , was isolated from the rhizosphere soil of Podocarpus rumphii in Laiwangi Wanggameti National Park, Indonesia. A comprehensive polyphasic approach was used to determine its taxonomic position. Strain SMS 1(5)a T exhibited the highest 16S rRNA gene sequence similarity to Peterkaempfera griseoplana NRRL B-3064 T (98.89%), followed by Peterkaempfera bronchialis DSM 106435 T (98.68%). Phylogenetic and phylogenomic analyses confirmed its affiliation with the genus Peterkaempfera . The genome size of strain SMS 1(5)a T was 8.8 Mb, with a DNA G+C content of 72 mol%. Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain SMS 1(5)a T and P. griseoplana NRRL B-3064 T were 41.9 and 90.47%, respectively, which were below the established thresholds for species delineation. Strain SMS 1(5)a T grew between 15 and 40 °C, within a pH range of 5–8, and showed tolerance to 0–2% (w/v) NaCl. The morphological and chemotaxonomic properties of strain SMS 1(5)a T were consistent with those of Peterkaempfera . The strain formed long, flexuous-to-spiral spore chains with a warty surface. The whole-cell hydrolysates of strain SMS 1(5)a T contained ll -diaminopimelic acid ( ll -DAP) as the diagnostic diamino acid as well as whole-cell sugars, including glucose, mannose and ribose. The predominant menaquinone was MK-9(H8), and its polar lipid profile included phosphatidylethanolamine (PE), phosphatidylinositol (PI) and diphosphatidylglycerol (DPG). Additionally, the major fatty acid in strain SMS 1(5)aᵀ was iso -C 15:0 , differentiating it from the other two type strains. Characterization based on genotypic, genomic, phenotypic and chemotaxonomic studies suggests strain SMS 1(5)a T as a novel species of the genus Peterkaempfera , for which the name Peterkaempfera podocarpi sp. nov. (type strain SMS 1(5)a T = InaCC A1244 T = NBRC 116964 T ) is proposed.