aromatic polyketides
Recently Published Documents


TOTAL DOCUMENTS

103
(FIVE YEARS 31)

H-INDEX

25
(FIVE YEARS 4)

2022 ◽  
Vol 193 ◽  
pp. 113012
Author(s):  
Yi Zang ◽  
Yihua Gong ◽  
Zhengyi Shi ◽  
Changxing Qi ◽  
Chunmei Chen ◽  
...  

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jingyan Zhang ◽  
Ying Sun ◽  
Yeji Wang ◽  
Xin Chen ◽  
Lu Xue ◽  
...  

Abstract Background Rubiginones belong to the angucycline family of aromatic polyketides, and they have been shown to potentiate the vincristine (VCR)-induced cytotoxicity against VCR-resistant cancer cell lines. However, the biosynthetic gene clusters (BGCs) and biosynthetic pathways for rubiginones have not been reported yet. Results In this study, based on bioinformatics analysis of the genome of Streptomyces sp. CB02414, we predicted the functions of the two type II polyketide synthases (PKSs) BGCs. The rub gene cluster was predicted to encode metabolites of the angucycline family. Scale-up fermentation of the CB02414 wild-type strain led to the discovery of eight rubiginones, including five new ones (rubiginones J, K, L, M, and N). Rubiginone J was proposed to be the final product of the rub gene cluster, which features extensive oxidation on the A-ring of the angucycline skeleton. Based on the production profiles of the CB02414 wild-type and the mutant strains, we proposed a biosynthetic pathway for the rubiginones in CB02414. Conclusions A genome mining strategy enabled the efficient discovery of new rubiginones from Streptomyces sp. CB02414. Based on the isolated biosynthetic intermediates, a plausible biosynthetic pathway for the rubiginones was proposed. Our research lays the foundation for further studies on the mechanism of the cytochrome P450-catalyzed oxidation of angucyclines and for the generation of novel angucyclines using combinatorial biosynthesis strategies.


2021 ◽  
pp. 1-9
Author(s):  
Yi-Wei Hu ◽  
Wei-Hao Chen ◽  
Meng-Meng Song ◽  
Xiao-Yan Pang ◽  
Xin-Peng Tian ◽  
...  

2021 ◽  
pp. 1-8
Author(s):  
Baiq Nila Sari Ningsih ◽  
Vatcharin Rukachaisirikul ◽  
Supansa Pansrinun ◽  
Souwalak Phongpaichit ◽  
Sita Preedanon ◽  
...  

Toxins ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 261
Author(s):  
Dan Xu ◽  
Mengyao Xue ◽  
Zhen Shen ◽  
Xiaowei Jia ◽  
Xuwen Hou ◽  
...  

Fungal phytotoxic secondary metabolites are poisonous substances to plants produced by fungi through naturally occurring biochemical reactions. These metabolites exhibit a high level of diversity in their properties, such as structures, phytotoxic activities, and modes of toxicity. They are mainly isolated from phytopathogenic fungal species in the genera of Alternaria, Botrytis, Colletotrichum, Fusarium, Helminthosporium, and Phoma. Phytotoxins are either host specific or non-host specific phytotoxins. Up to now, at least 545 fungal phytotoxic secondary metabolites, including 207 polyketides, 46 phenols and phenolic acids, 135 terpenoids, 146 nitrogen-containing metabolites, and 11 others, have been reported. Among them, aromatic polyketides and sesquiterpenoids are the main phytotoxic compounds. This review summarizes their chemical structures, sources, and phytotoxic activities. We also discuss their phytotoxic mechanisms and structure–activity relationships to lay the foundation for the future development and application of these promising metabolites as herbicides.


Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1959
Author(s):  
Hua Xiao ◽  
Guiyang Wang ◽  
Zhengdong Wang ◽  
Yi Kuang ◽  
Juan Song ◽  
...  

Angucyclinones are aromatic polyketides that possess impressive structural diversity and significant biological activities. The structural diversity of these natural products is attributed to various enzymatic or nonenzymatic modifications on their tetracyclic benz(a)anthracene skeleton. Previously, we discovered an unusual phenylamine-incorporated angucyclinone (1) from a marine Streptomyces sp. PKU-MA00218, and identified that it was produced from the nonenzymatic conversion of a C-ring-cleaved angucyclinone (2) with phenylamine. In this study, we tested the nonenzymatic conversion of 2 with more phenylamine analogues, to expand the utility of this feasible conversion in unusual angucyclinones generation. The (3-ethynyl)phenylamine and disubstituted analogues including (3,4-dimethyl)phenylamine, (3,4-methylenedioxy)phenylamine, and (4-bromo-3-methyl)phenylamine were used in the conversion of 2, which was isolated from the fermentation of Streptomyces sp. PKU-MA00218. All four phenylamine analogues were incorporated into 2 efficiently under mild conditions, generating new compounds 3–6. The activation of 3–6 on nuclear factor erythroid 2-related factor 2 (Nrf2) transcription were tested, which showed that 4 possessing a dimethyl-substitution gave most potent activity. These results evidenced that disubstitutions on phenylamine can be roughly tolerated in the nonenzymatic reactions with 2, suggesting extended applications of more disubstituted phenylamines incorporation to generate new bioactive angucyclinones in the future.


Author(s):  
Sara M Stricker ◽  
Bruce D. Gossen ◽  
Mary Ruth McDonald

The fungal genus <i>Stemphylium</i> (phylum Ascomycota, teleomorph <i>Pleospora</i>) includes plant pathogenic, endophytic, and saprophytic species with worldwide distributions. <i>Stemphylium<i></i> spp. produce prodigious numbers of air-borne spores, so are a human health concern as allergens. Some species also produce secondary metabolites such as glucosides, ferric chelates, aromatic polyketides, and others that function as toxins that damage plants and other fungal species. Some of these compounds also exhibit a low level of mammalian toxicity. The high production of air-borne spores by this genus can result in a high incidence of human exposure. Concern about toxin production appears to be the reason that <i></i>S. vesicarium<i></i>, which is a pathogen of several vegetable crops, was classified in Canada as a potential risk of harm to humans for many years. A detailed assessment of the risk of exposure was provided to the relevant regulatory body, Public Health Agency of Canada. They determined that <i></i>Stemphylium<i></i> spp., in nature or under laboratory conditions, posed little to no risk to humans or animals, and the species was re-assigned as a basic (level 1) risk agent.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Britta Frensch ◽  
Thorsten Lechtenberg ◽  
Michel Kather ◽  
Zeynep Yunt ◽  
Martin Betschart ◽  
...  

AbstractThe structural complexity and bioactivity of natural products often depend on enzymatic redox tailoring steps. This is exemplified by the generation of the bisbenzannulated [5,6]-spiroketal pharmacophore in the bacterial rubromycin family of aromatic polyketides, which exhibit a wide array of bioactivities such as the inhibition of HIV reverse transcriptase or DNA helicase. Here we elucidate the complex flavoenzyme-driven formation of the rubromycin pharmacophore that is markedly distinct from conventional (bio)synthetic strategies for spiroketal formation. Accordingly, a polycyclic aromatic precursor undergoes extensive enzymatic oxidative rearrangement catalyzed by two flavoprotein monooxygenases and a flavoprotein oxidase that ultimately results in a drastic distortion of the carbon skeleton. The one-pot in vitro reconstitution of the key enzymatic steps as well as the comprehensive characterization of reactive intermediates allow to unravel the intricate underlying reactions, during which four carbon-carbon bonds are broken and two CO2 become eliminated. This work provides detailed insight into perplexing redox tailoring enzymology that sets the stage for the (chemo)enzymatic production and bioengineering of bioactive spiroketal-containing polyketides.


Sign in / Sign up

Export Citation Format

Share Document