JBIR-17, a novel trichostatin analog from Streptomyces sp. 26634

Ulleunganilines A-C, Trichostatin Analogues Bearing a Modified Side Chain from Streptomyces sp. 13F051

Three new trichostatin analogues, ulleunganilines A-C (1-3), and seven known trichostatins (4-10) were isolated from cultures of Streptomyces sp. 13F051. NMR, UV, and MS data indicated that the planar structures of 1-3 consisted of modified side chains in the trichostatic acid moiety. The absolute configuration of the 2,4-dimethyl-branched carbon chains in 1 and 2 was determined by the PGME method, while the amino acid group in 3 was identified by advanced Marfey's method. Based on the structure of the modified side chains, the origin of 1-3 is proposed. Further experiments indicated that 1 and 3 displayed moderate histone deacetylase inhibitory activity, suggesting that not only the hydroxamate group but also the N,N-dimethyl group were essential for the inhibitory activity.

Marine-Derived Secondary Metabolites as Promising Epigenetic Bio-Compounds for Anticancer Therapy

Sessile organisms such as seaweeds, corals, and sponges continuously adapt to both abiotic and biotic components of the ecosystem. This extremely complex and dynamic process often results in different forms of competition to ensure the maintenance of an ecological niche suitable for survival. A high percentage of marine species have evolved to synthesize biologically active molecules, termed secondary metabolites, as a defense mechanism against the external environment. These natural products and their derivatives may play modulatory roles in the epigenome and in disease-associated epigenetic machinery. Epigenetic modifications also represent a form of adaptation to the environment and confer a competitive advantage to marine species by mediating the production of complex chemical molecules with potential clinical implications. Bioactive compounds are able to interfere with epigenetic targets by regulating key transcriptional factors involved in the hallmarks of cancer through orchestrated molecular mechanisms, which also establish signaling interactions of the tumor microenvironment crucial to cancer phenotypes. In this review, we discuss the current understanding of secondary metabolites derived from marine organisms and their synthetic derivatives as epigenetic modulators, highlighting advantages and limitations, as well as potential strategies to improve cancer treatment.

Heterologous expression of the trichostatin gene cluster and functional characterization ofN-methyltransferase TsnB8

N-Methyltransferase TsnB8 was demonstrated to catalyze successive methyltransfer reactions in the biosynthesis of trichostatin.

Biomedical Applications of Enzymes From Marine Actinobacteria

Marine microbial enzyme technologies have progressed significantly in the last few decades for different applications. Among the various microorganisms, marine actinobacterial enzymes have significant active properties, which could allow them to be biocatalysts with tremendous bioactive metabolites. Moreover, marine actinobacteria have been considered as biofactories, since their enzymes fulfill biomedical and industrial needs. In this chapter, the marine actinobacteria and their enzymes' uses in biological activities and biomedical applications are described.

A new trichostatin analog from Streptomyces sp. CPCC 203909

A new trichostatin analog (1) and two known analogs (2, 3) have been isolated from the rice fermentation of the Streptomyces sp. CPCC 203909. Their structures were determined by spectroscopic and chemical methods. The absolute configurations of 1 were assigned by Marfey's method, combined with comparing the NMR and circular dichroism spectroscopic data of 2 and 3. Compound 1 showed cytotoxicity against human embryonic kidney 293 cell line with IC50 value of 39.2 μM.

Discovery and mechanism of natural products as modulators of histone acetylation

Small molecules that modulate histone acetylation by targeting key enzymes mediating this posttranslational modification - histone acetyltransferases and histone deacetylases - are validated chemotherapeutic agents for the treatment of cancer. This area of research has seen a rapid increase in interest in the past decade, with the structurally diverse natural products-derived compounds at its forefront. These secondary metabolites from various biological sources target this epigenetic modification through distinct mechanisms of enzyme regulation by utilizing a diverse array of pharmacophores. We review the discovery of these compounds and discuss their modes of inhibition together with their downstream biological effects.

Trichostatin analogues JBIR-109, JBIR-110, and JBIR-111 from the marine sponge-derived Streptomyces sp. RM72

Three new trichostatin analogues, JBIR-109 (1), JBIR-110 (2), and JBIR-111 (3), were isolated from the culture of the marine sponge-derived Streptomyces sp. strain RM72, together with trichostatin A (4) and trichostatic acid (5). The planar structures of 1-3 were determined on the basis of extensive NMR and MS analyses. In addition, the absolute configurations of the amino acid residues were determined by Marfey's method. The histone deacetylase inhibitory activities of 1-5 were examined, and their structure-activity relationships are discussed.

Sponge-derived Streptomyces producing isoprenoids via the mevalonate pathway

In the course of our screening program for isoprenoids of marine actinobacterial origin, 523 actinobacterial strains were isolated from marine samples. Actinobacteria usually use the 2-C-methyl-d-erythritol 4-phosphate pathway for the production of primary metabolites, but some have been reported to use the mevalonate (MVA) pathway for the production of isoprenoids as secondary metabolites. 3-Hydroxy-3-methyl glutaryl coenzyme A reductase (HMGR) is a key enzyme and plays an important role in the MVA pathway. Therefore, we screened strains possessing the HMGR gene from the 523 strains mentioned above and also investigated isoprenoid compounds from cultures of strains possessing HMGR genes. As a result, Streptomyces sp. SpC080624SC-11 isolated from a marine sponge, Cinachyra sp., was shown to possess the HMGR gene and produce novel isoprenoids, JBIR-46 (1), -47 (2), and -48 (3). On the basis of extensive NMR and MS analyses, the structures of 1-3 were determined to be phenazine derivatives harboring dimethylallyl moieties. Furthermore, the isoprene units of 2 and 3 were confirmed to be synthesized via the MVA pathway in a feeding experiment using [1-(13)C]acetate.