Nikkomycins are competitive inhibitors of chitin synthase and inhibit the growth of filamentous fungi, insects, acarids and yeasts. The gene cluster responsible for biosynthesis of nikkomycins has been cloned and the biosynthetic pathway was elucidated at the genetic, enzymatic and regulatory levels.
Results:
Streptomyces ansochromogenes DeltasanL was constructed by homologous recombination and the mutant strain was fed with benzoic acid, 4-hydroxybenzoic acid, nicotinic acid and isonicotinic acid.
Two novel nikkomycin analogues were produced when cultures were supplemented with nicotinic acid. These two compounds were identified as nikkomycin Px and Pz by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR).
Bioassays against Candida albicans and Alternaria longipes showed that nikkomycin Px and Pz exhibited comparatively strong inhibitory activity as nikkomycin X and Z produced by Streptomyces ansochromogenes 7100 (wild-type strain). Moreover, nikkomycin Px and Pz were found to be more stable than nikkomycin X and Z at different pH and temperature conditions.
Conclusions:
Two novel nikkomycin analogues (nikkomycin Px and Pz) were generated by mutasynthesis with the sanL inactivated mutant of Streptomyces ansochromogenes 7100.
Although antifungal activities of these two compounds are similar to those of nikkomycin X and Z, their stabilities are much better than nikkomycin X and Z under different pHs and temperatures.
Author: Chi FengHongbo LingDeyao DuJihui ZhangGuoqing NiuHuarong Tan
Credits/Source: Microbial Cell Factories 2014, 13:59
Published on: 2014-04-21
Tweet
News Provider: 7thSpace Interactive
Social Bookmarking
RETWEET This! | Digg this! | Post to del.icio.us | Post to Furl | Add to Netscape | Add to Yahoo! | Rojo
There are no comments available. Be the first to write a comment.