TitleModulation of Specialized Metabolite Production in Genetically Engineered .
Publication TypeJournal Article
Year of Publication2021
AuthorsJu Z, Zhou W, Alharbi HA, Howell DC, Mahmud T
JournalACS Chem Biol
Date Published2021 Nov 19
KeywordsAnti-Bacterial Agents, Antineoplastic Agents, Cell Line, Tumor, Drug Screening Assays, Antitumor, Genes, Bacterial, HSP90 Heat-Shock Proteins, Humans, Microbial Sensitivity Tests, Molecular Structure, Organisms, Genetically Modified, Oxazoles, Polyketide Synthases, Polyketides, Protein Binding, Streptomyces, Substrate Specificity

Filamentous soil bacteria are known to produce diverse specialized metabolites. Despite having enormous potential as a source of pharmaceuticals, they often produce bioactive metabolites at low titers. Here, we show that inactivation of the pactamycin, NFAT-133, and conglobatin biosynthetic pathways in ATCC 27456 significantly increases the production of the mitochondrial electron transport inhibitors piericidins. Similarly, inactivation of the pactamycin, NFAT-133, and piericidin pathways significantly increases the production of the heat-shock protein (Hsp) 90 inhibitor conglobatin. In addition, four new conglobatin analogues (B2, B3, F1, and F2) with altered polyketide backbones, together with the known analogue conglobatin B1, were identified in this mutant, indicating that the conglobatin biosynthetic machinery is promiscuous toward different substrates. Among the new conglobatin analogues, conglobatin F2 showed enhanced antitumor activity against HeLa and NCI-H460 cancer cell lines compared to conglobatin. Conglobatin F2 also inhibits colony formation of HeLa cells in a dose-dependent manner. Molecular modeling studies suggest that the new conglobatins bind to human Hsp90 and disrupt Hsp90/Cdc37 chaperone/co-chaperone interactions in the same manner as conglobatin. The study also showed that genes that are involved in piericidin biosynthesis are clustered in two different loci located distantly in the genome.

Alternate JournalACS Chem Biol
PubMed ID34723462
PubMed Central IDPMC8604789
Grant ListR01 AI129957 / AI / NIAID NIH HHS / United States
S10 OD018518 / OD / NIH HHS / United States