Characterization of Streptomyces piniterrae sp. nov. and Identification of the Putative Gene Cluster Encoding the Biosynthesis of Heliquinomycins

Abstract

A novel actinomycete producing heliquinomycin and 9’-methoxy-heliquinomycin, designated strain jys28T, was isolated from rhizosphere soil of Pinus yunnanensis and characterized using a polyphasic approach. The strain had morphological characteristics and chemotaxonomic properties identical to those of members of the genus Streptomyces. It formed spiral chains of spores with spiny surfaces. The menaquinones detected were MK-9(H6), MK-9(H8) and MK-9(H4). The major fatty acids were iso-C16:0, C15:0, C16:1ω7с and anteiso-C15:0. The phospholipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine and phosphatidylinositol mannoside. The DNA G + C content of the draft genome sequence, consisting of 8.5 Mbp, was 70.6%. Analysis of the 16S rRNA gene sequence showed that strain jys28T belongs to the genus Streptomyces with the highest sequence similarities to Streptomyces chattanoogensis NBRC 13058T (99.2%) and Streptomyces lydicus DSM 40002T (99.2%) and phylogenetically clustered with them. Multilocus sequence analysis based on five other house-keeping genes (atpD, gyrB, rpoB, recA and trpB) and the low level of DNA–DNA relatedness and phenotypic differences allowed the novel isolate to be differentiated from its most closely related strains. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces piniterrae sp. nov. is proposed. Furthermore, the putative biosynthetic gene cluster of heliquinomycins was identified and the biosynthetic pathway was discussed. The type strain is jys28T (=CCTCC AA 2018051T =DSM 109823T).

Enzymatic spiroketal formation via oxidative rearrangement of pentangular polyketides

“…Furthermore, genomic data suggest that the biosynthetic gene clusters for production of spiroketal-containing 1 (S. sp. JP95), 2 (of S. collinus) 15 , hyaluromycin (of S. hyaluromycini MB-PO13) 27 , and of heliquinomycin (S. piniterrae) 28 harbor grhO5, grhO1, and grhO6 homologs (the genome of the Fig. 3 Proposed spiroketal formation in rubromycin polyketide biosynthesis.…”

Characterization of a Novel Endophytic Actinomycete, Streptomyces physcomitrii sp. nov., and Its Biocontrol Potential Against Ralstonia solanacearum on Tomato

“…Growth at different temperatures (4,10,15,20,28,35,37,40, and 45 • C) was determined on ISP3 medium after incubation for 14 days. Tolerance of pH range (pH 4-12, at intervals of 1 pH units), using a buffer system, was described by Zhao et al [23], and NaCl tolerance (0-12%, with an interval of 1%, w/v) for growth was determined after 3 days of growth in TSB broth [24] in shake flasks (250 rpm) at 28 • C. The utilization of sole carbon and nitrogen sources was carried out, as described previously [25]. Other physiological and biochemical characteristics were conducted, according to a previous report [26].…”

Genome mining of Streptomyces sp. CB00271 as a natural high‐producer of β‐rubromycin and the resulting discovery of β‐rubromycin acid

“…The availability of alternative producers enabled us to circumvent common deficiencies of original wild-type strains, such as low production titers, unfavorable growth, and poor genetic amenability et al (Krug & Muller, 2014), which shall greatly facilitate subsequent practical development of desired natural products. Among discovered 20 RUBs, only the biosynthetic gene clusters (BGCs) of β-RUB (1) (rub), GRH (grh), HYL (hyl) and heliquinomycin (HLQ) (hlq) have been identified (Harunari et al, 2018;Yunt et al, 2009;Zhuang et al, 2020). Although RUBs are derived from a Type-II polyketide synthase pathway, their post tailoring steps remain elusive, especially the tautomerization of β-RUB (1).…”

“…Among discovered 20 RUBs, only the biosynthetic gene clusters (BGCs) of β‐RUB ( 1 ) ( rub ), GRH ( grh ), HYL ( hyl ) and heliquinomycin (HLQ) ( hlq ) have been identified (Harunari et al, 2018; Yunt et al, 2009; Zhuang et al, 2020). Although RUBs are derived from a Type‐II polyketide synthase pathway, their post tailoring steps remain elusive, especially the tautomerization of β‐RUB ( 1 ).…”