Transcriptome analysis of the regulation of natamycin biosynthesis in Streptomyces natalensis HW-2 by fungal elicitor

Abstract

Background Natamycin is a polyene macrolide polyketide antibiotics and used in 150 countries as a natural food preservative. Streptomyces natalensis is an important producer. Elicitation had been approved to be an effective method to improve the biosynthesis of secondary metabolites. Fungal elicitor from Penicillium chrysogenum AS 3.5163 showed inductive effect on the biosynthesis of natamycin in S. natalensis HW-2 fermentation. However, regarding the global gene expression of natamycin in response to fungal elicitor is not still reported. Results RNA-Seq analysis showed that there were 1265 differential expression genes (DEGs) at 40 h and 2196 DEGs at 80 h. The fungal elicitor had stronger effects on the transcription level of S. natalensis HW-2 at 80 h than that at 40 h. Gene Ontology (GO) enrichment analysis of DEGs showed significant enrichment in biological processes. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the fungal elicitor mainly affected the expression levels of some genes about cellular process, metabolism and genetic information, especially in pentose phosphate pathway (PPP), glycolytic pathway (EMP) and tricarboxylic acid cycle (TCA). KEGG pathway showed that fungal elicitor had a greater influence on the metabolism of branched-chain amino acids (BCAAs). Among them, 23 DEGs associated with BCAAs metabolism were up-regulated or down-regulated. The supplementation experiment with BCAAs confirmed that 0.2 g/L of L-Ile and 0.5 g/L of L-Val increased natamycin yield by 17.6% and 37.8%, respectively. Fungal elicitor also up-regulated the transcriptional levels of most of the enzymes associated with the biosynthesis of natamycin and two important transcription regulators ( pimR and pimM ). To confirm the accuracy of RNA-Seq, the results of qPCR showed that these gene expression levels were in agreement with the transcription changes by RNA-Seq. Conclusion In this study, the change of transcriptional levels in S. natalensis HW-2 under treated with the fungal elicitor was firstly reported. The major finding of our comparative transcriptome analysis is that the fungal elicitor improves the supply of precursor, and alters the expression of natamycin related genes and regulator of secondary metabolism. From our results, we conclude that regulatory alterations are important factors for the enhancement of natamycin.

Elicitation for activation of the actinomycete genome's cryptic secondary metabolite gene clusters

“…The main conclusion is that the fungal elicitor increases the amount of precursor and changes the expression of natamycin related genes and secondary metabolic regulators. 45 …”

Effect of Alcaligenes sp. on corrosion behavior of X65 steel in simulated offshore oilfield-produced water

“…is shown in Figure 6C. A total of antibacterial substances (Hydroxyphenyl lactic acid, Phenyl lactic acid, Butane dioic acid, 2,3-Butanediol, Natamycin, Caffeic acid, Glucoside, Gallic acid, Neomycin, Lymecycline, Kanamycin, Ganoderic acid B, Ganoderic acid S, 1,4-Dihydroxyanthraquinone; 23.01%; Zheng et al, 2019Zheng et al, , 2020Wang et al, 2020Wang et al, , 2021aAbdul-Rahim et al, 2021;Sorgi et al, 2021;Gu et al, 2022;Selvaraj et al, 2022;Wu et al, 2023), corrosion inhibitors (4.31%), amino acids (37.99%), polysaccharides (9.16%), nucleosides (2.21%), phospholipids (3.62%), alkaloids (7.41%), organic acids (7.05%), and other substances (5.24%). The highest relative percentages and the largest variety of substances were amino acids, followed by antibacterial substances.…”