Alchivemycin A, a Bioactive Polycyclic Polyketide with an Unprecedented Skeleton from Streptomyces sp.

Abstract

Alchivemycin A, a novel polycyclic polyketide, was isolated from the culture extract of a plant-derived actinomycete Streptomyces sp. The structure and relative configuration were elucidated by spectroscopic analysis and X-ray crystallography, and the absolute configuration was determined by a (1)H NMR anisotropy method using MPA ester derivatization. The new compound contains an unprecedented heterocyclic ring system, 2H-tetrahydro-4,6-dioxo-1,2-oxazine. Alchivemycin A showed potent antimicrobial activity against Micrococcus luteus and inhibitory effects on tumor cell invasion.

Draft genome sequence of Streptomyces sp. TP-A0867, an alchivemycin producer

“…TP-A0867 was isolated from a leaf of a Chinese chive ( Allium tuberosum ) collected in Toyama, Japan [2] and two new polyketides, alchivemycins A and B, were found from its culture broth [4, 5]. The characteristics of Streptomyces sp.…”

“…In our continuing search for structurally rare metabolites from Streptomyces , alchivemycins A and B, which have potent antimicrobial activity and inhibitory effects on tumor cell invasion, were discovered from a plant-derived Streptomyces strain TP-A0867. These compounds are novel polycyclic polyketides with an unprecedented carbon backbone [4, 5], however the biosynthetic gene cluster has not been known to date. In this study, we performed whole genome shotgun sequencing of the strain TP-A0867 to elucidate the biosynthetic pathway of alchivemycins.…”

Simamycin (5′-O-geranyluridine): a new prenylated nucleoside from Streptomyces sp.

“…1 However, it is noteworthy that the number of metabolites isolated is far below the number of gene clusters for secondary metabolite biosynthesis present in the genome of Streptomyces species. 2,3 In our screening for structurally unique or rare secondary metabolites from Streptomyces, we isolated plant hormone-like spiroacetals of polyketide origin, 4 a linear polyketide δ-lactone with antimetastatic property, 5 macrocyclic polyketides with a biosynthetically unprecedented heterocyclic ring structure 6 and methylphenylalanine derivatives with adipocyte differentiation promoting activity. 7 Further attempts to obtain new bioactive compounds from Streptomyces, a soil-derived strain TP-A0872, was chosen for chemical investigation, which led to the isolation of a new geranylated nucleoside, simamycin (1; Figure 1).…”

Catechoserine, a new catecholate-type inhibitor of tumor cell invasion from Streptomyces sp.

“…Although it is not clear whether the phylogenic novelty is associated with the production ability of new compounds, recent studies have shown the occurrence of new metabolites in Streptomyces species that have a low 16S rRNA gene sequence homology to the known species. [5][6][7] In our continuing investigation on chemical diversity within this group, [8][9][10] a Streptomyces strain that shared a low 16S rRNA gene identity (96.3%) with the nearest type strain for S. albus was found to produce a new catecholate derivative, catechoserine (1), along with two known biosynthetically related metabolites, N,N¢-bis (2,3- (2) and N,N¢,N¢-tris (2,3- (3) (Figure 1).…”