Streptomyces aquilus sp. nov., a novel actinomycete isolated from a Chinese medicinal plant

Abstract

The taxonomic position of a novel actinomycete isolate, designated strain GGCR-6T, isolated from the healthy leaves of Xanthium sibiricum collected from the botanic garden of Hunan University of Science and Technology in Hunan province, PR China, was determined by a polyphasic approach. GGCR-6T grew well on ISP series media and formed well-developed, branched substrate hyphae and aerial mycelium that differentiated into straight spore chains consisting of cylindrical spores with smooth surfaces. The diagnostic diamino acid was ll-diaminopimelic acid. The major menaquinones were MK-9(H8), MK-9(H2), MK-9 and MK-9(H6). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphotidylinositol and phosphatidylinositol mannosides. The predominant fatty acids were C16 : 1ω9c, iso-C16 : 0 and C16 : 0. The phenotypic characteristics of GGCR-6T indicated that it represented a member of the genus Streptomyces . Phylogenetic analysis based on the 16S rRNA gene sequence indicated that GGCR-6T was most closely related to Streptomyces cyaneus NRRL B2296T and Streptomyces griseoruber NRRL B1818T. However, the digital DNA–DNA hybridization, the average nucleotide identity and the multi locus sequence analysis evolutionary distance clearly separate GGCR-6T from the phylogenetically closely related species. Furthermore, the novel isolate was distinctly differentiated from S. cyaneus NRRL B2296T and S. griseoruber NRRL B1818T by morphological, physiological and biochemical characteristics. Based on these data, strain GGCR-6T should be designated as a representative of a novel species of the genus Streptomyces , for which the name Streptomyces aquilus sp. nov. is proposed. The type strain is strain GGCR-6T (=CICC 11055T=JCM 33584T).

Streptomyces liliifuscus sp. nov and an anti-ginger plague agent Streptomyces liliiviolaceus sp. nov, two novel species isolated from soil of Lilium lancifolium

“…members of the genus Streptomyces are characterized by radial growth and the cell wall diagnostic amino acids ( l , l -diaminopimelic acid), distinguishing it from other genera. Previous research has explored the ginger blast inhibition potential of antagonistic actinomycetes isolated from wetlands [16], medicinal plants [17, 18] and heavy metal-contaminated soils in Hunan Province [19, 20]. Interestingly, two strains of members of the genus Streptomyces , ZYC-3 T and BH-SS-21 T , have been recently isolated from Lilium lancifolium , with up to 98.4% similarity in their 16S rRNA gene sequences [21, 22].…”

Streptomyces genisteinicus sp. nov., a novel genistein-producing actinomycete isolated from a Chinese medicinal plant and proposal of Streptomyces michiganensis Corbaz et al. 1957 as a later heterotypic synonym of Streptomyces xanthochromogenes Arishima et al. 1956

“…Strain CRPJ-33 T was isolated and purified by the methods described by Li et al . [16]. The purified isolate was maintained on Gauze’s synthetic medium [17] at 4 °C and preserved at −80 °C in a 30 % (w/v) glycerol suspension.…”

Genome-based classification of the Streptomyces violaceusniger clade and description of Streptomyces sabulosicollis sp. nov. from an Indonesian sand dune

“…The classification of Streptomyces species is especially challenging given the high number of validly published species ( https://www.bacterio.net.streptomyces.html ), the limited resolution of 16S rRNA gene sequences in their delineation (Labeda et al 2012 , 2017 ) and evidence that the genus is underspeciated (Yamac et al 2011 ; Hamm et al 2017 ). However, multi-locus sequence analyses (MLSA) of concatenated protein-coding house-keeping genes (Ayed et al 2018 ; Kusuma et al 2020 ; Li et al 2020 ; Martinet et al 2020 ) and comparative surveys of whole-genome sequences (Nouioui et al 2018 ) provide invaluable data for the circumscription of novel Streptomyces species. MLSA analyses have revealed a correlation between the delineation of phylogenetic clades and associated phenotypic properties (Rong and Huang 2014 ; Labeda et al 2014 ), as exemplified by the assignment of streptomycetes with spiral chains of rugose ornamented spores to a well supported taxon (Labeda et al 2017 ), known as the Streptomyces violaceusniger clade (Sembiring et al 2000 ; Kumar and Goodfellow 2008 , 2010 ).…”