scholarly journals Comparative transcriptomic analysis reveals the significant pleiotropic regulatory effects of LmbU on lincomycin biosynthesis

2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Chun-Yan Lin ◽  
Ai-Ping Pang ◽  
Yue Zhang ◽  
Jianjun Qiao ◽  
Guang-Rong Zhao
Keyword(s):  
Transcriptional Regulator ◽  
Gene Clusters ◽  
Transcriptomic Analysis ◽  
Regulatory Function ◽  
Antibiotic Biosynthesis ◽  
Gram Positive Bacteria ◽  
Drug Flux ◽  
Regulatory Effects ◽  
Streptomyces Lincolnensis ◽  
Comparative Transcriptomic Analysis

Abstract Background Lincomycin, produced by Streptomyces lincolnensis, is a lincosamide antibiotic and widely used for the treatment of the infective diseases caused by Gram-positive bacteria. The mechanisms of lincomycin biosynthesis have been deeply explored in recent years. However, the regulatory effects of LmbU that is a transcriptional regulator in lincomycin biosynthetic (lmb) gene cluster have not been fully addressed. Results LmbU was used to search for homologous LmbU (LmbU-like) proteins in the genomes of actinobacteria, and the results showed that LmbU-like proteins are highly distributed regulators in the biosynthetic gene clusters (BGCs) of secondary metabolites or/and out of the BGCs in actinomycetes. The overexpression, inactivation and complementation of the lmbU gene indicated that LmbU positively controls lincomycin biosynthesis in S. lincolnensis. Comparative transcriptomic analysis further revealed that LmbU activates the 28 lmb genes at whole lmb cluster manner. Furthermore, LmbU represses the transcription of the non-lmb gene hpdA in the biosynthesis of l-tyrosine, the precursor of lincomycin. LmbU up-regulates nineteen non-lmb genes, which would be involved in multi-drug flux to self-resistance, nitrate and sugar transmembrane transport and utilization, and redox metabolisms. Conclusions LmbU is a significant pleiotropic transcriptional regulator in lincomycin biosynthesis by entirely activating the lmb cluster and regulating the non-lmb genes in Streptomyces lincolnensis. Our results first revealed the pleiotropic regulatory function of LmbU, and shed new light on the transcriptional effects of LmbU-like family proteins on antibiotic biosynthesis in actinomycetes.

scholarly journals The Novel Transcriptional Regulator LmbU Promotes Lincomycin Biosynthesis through Regulating Expression of Its Target Genes in Streptomyces lincolnensis

2017 ◽  
Vol 200 (2) ◽  
Author(s):  
Bingbing Hou ◽  
Yanwei Lin ◽  
Haizhen Wu ◽  
Meijin Guo ◽  
Hrvoje Petkovic ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Target Genes ◽  
Regulatory Mechanism ◽  
Transcriptional Regulator ◽  
Gene Clusters ◽  
Saccharopolyspora Erythraea ◽  
Transcriptional Analysis ◽  
Biosynthetic Gene ◽  
Content Type ◽  
Streptomyces Lincolnensis

ABSTRACT Lincomycin A is a clinically important antimicrobial agent produced by Streptomyces lincolnensis . In this study, a new regulator designated LmbU (GenBank accession no. ABX00623.1) was identified and characterized to regulate lincomycin biosynthesis in S. lincolnensis wild-type strain NRRL 2936. Both inactivation and overexpression of lmbU resulted in significant influences on lincomycin production. Transcriptional analysis and in vivo neomycin resistance (Neo r ) reporter assays demonstrated that LmbU activates expression of the lmbA , lmbC , lmbJ , and lmbW genes and represses expression of the lmbK and lmbU genes. Electrophoretic mobility shift assays (EMSAs) demonstrated that LmbU can bind to the regions upstream of the lmbA and lmbW genes through the consensus and palindromic sequence 5′-CGCCGGCG-3′. However, LmbU cannot bind to the regions upstream of the lmbC , lmbJ , lmbK , and lmbU genes as they lack this motif. These data indicate a complex transcriptional regulatory mechanism of LmbU. LmbU homologues are present in the biosynthetic gene clusters of secondary metabolites of many other actinomycetes. Furthermore, the LmbU homologue from Saccharopolyspora erythraea (GenBank accession no. WP_009944629.1) also binds to the regions upstream of lmbA and lmbW , which suggests widespread activity for this regulator. LmbU homologues have no significant structural similarities to other known cluster-situated regulators (CSRs), which indicates that they belong to a new family of regulatory proteins. In conclusion, the present report identifies LmbU as a novel transcriptional regulator and provides new insights into regulation of lincomycin biosynthesis in S. lincolnensis . IMPORTANCE Although lincomycin biosynthesis has been extensively studied, its regulatory mechanism remains elusive. Here, a novel regulator, LmbU, which regulates transcription of its target genes in the lincomycin biosynthetic gene cluster ( lmb gene cluster) and therefore promotes lincomycin biosynthesis, was identified in S. lincolnensis strain NRRL 2936. Importantly, we show that this new regulatory element is relatively widespread across diverse actinomycetes species. In addition, our findings provide a new strategy for improvement of yield of lincomycin through manipulation of LmbU, and this approach could also be evaluated in other secondary metabolite gene clusters containing this regulatory protein.

scholarly journals Comparative transcriptomic analysis reveals the regulatory effects of inorganic nitrogen on the biosynthesis of Monascus pigments and citrinin

RSC Advances ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 5268-5282
Author(s):  
Jia-Li Hong ◽  
Li Wu ◽  
Jin-Qiang Lu ◽  
Wen-Bin Zhou ◽  
Ying-Jia Cao ◽  
...  
Keyword(s):  
Rna Sequencing ◽  
Regulatory Mechanism ◽  
Inorganic Nitrogen ◽  
Transcriptomic Analysis ◽  
Monascus Pigments ◽  
Regulatory Effects ◽  
Comparative Transcriptomic Analysis

Comparative transcriptional approach (RNA sequencing combined with RT-qPCR) was used to investigate the regulatory mechanism of inorganic nitrogen on the biosynthesis of MPs and citrinin.

scholarly journals Restoration of Bioactive Lantibiotic Suicin from a RemnantlanLocus of Pathogenic Streptococcus suis Serotype 2

2013 ◽  
Vol 80 (3) ◽  
pp. 1062-1071 ◽  
Author(s):  
Jian Wang ◽  
Yong Gao ◽  
Kunling Teng ◽  
Jie Zhang ◽  
Shutao Sun ◽  
...  
Keyword(s):  
Gene Promoter ◽  
Streptococcus Suis ◽  
Gene Clusters ◽  
Disulfide Bridge ◽  
Gram Positive ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
System A ◽  
Bactericidal Activities

ABSTRACTLantibiotics are ribosomally synthesized, posttranslationally modified antimicrobial peptides. Their biosynthesis genes are usually organized in gene clusters, which are mainly found in Gram-positive bacteria, including pathogenic streptococci. Three highly virulentStreptococcus suisserotype 2 strains (98HAH33, 05ZYH33, and SC84) have been shown to contain an 89K pathogenicity island. Here, on these islands, we unveiled and reannotated a putative lantibiotic locus designatedsuiwhich contains a virulence-associated two-component regulator,suiK-suiR. In silicoanalysis revealed that the putative lantibiotic modification genesuiMwas interrupted by a 7.9-kb integron and that other biosynthesis-related genes contained various frameshift mutations. By reconstituting the intactsuiMinEscherichia colitogether with a semi-in vitrobiosynthesis system, a putative lantibiotic named suicin was produced with bactericidal activities against a variety of Gram-positive strains, including pathogenic streptococci and vancomycin-resistant enterococci. Ring topology dissection indicated that the 34-amino-acid lantibiotic contained two methyllanthionine residues and one disulfide bridge, which render suicin in an N-terminal linear and C-terminal globular shape. To confirm the function ofsuiK-suiR, SuiR was overexpressed and purified.In vitroanalysis showed that SuiR could specifically bind to thesuiAgene promoter. Its coexpression withsuiKcould activatesuiAgene promoter inLactococcus lactisNZ9000. Conclusively, we obtained a novel lantibiotic suicin by restoring its production from the remnantsuilocus and demonstrated that virulence-associated SuiK-SuiR regulates its production.

scholarly journals Extracellularly oxidative activation and inactivation of matured prodrug for cryptic self-resistance in naphthyridinomycin biosynthesis

2018 ◽  
Vol 115 (44) ◽  
pp. 11232-11237 ◽  
Author(s):  
Yue Zhang ◽  
Wan-Hong Wen ◽  
Jin-Yue Pu ◽  
Man-Cheng Tang ◽  
Liwen Zhang ◽  
...  
Keyword(s):  
Assembly Line ◽  
Antibiotic Biosynthesis ◽  
Bond Functionalization ◽  
Gram Positive Bacteria ◽  
Self Defense ◽  
Clinical Resistance ◽  
Reactive Chemicals ◽  
Peptide Synthetase ◽  
Oxidative Activation ◽  
Temporal And Spatial

Understanding how antibiotic-producing bacteria deal with highly reactive chemicals will ultimately guide therapeutic strategies to combat the increasing clinical resistance crisis. Here, we uncovered a distinctive self-defense strategy featured by a secreted oxidoreductase NapU to perform extracellularly oxidative activation and conditionally overoxidative inactivation of a matured prodrug in naphthyridinomycin (NDM) biosynthesis from Streptomyces lusitanus NRRL 8034. It was suggested that formation of NDM first involves a nonribosomal peptide synthetase assembly line to generate a prodrug. After exclusion and prodrug maturation, we identified a pharmacophore-inactivated intermediate, which required reactivation by NapU via oxidative C-H bond functionalization extracellularly to afford NDM. Beyond that, NapU could further oxidatively inactivate the NDM pharmacophore to avoid self-cytotoxicity if they coexist longer than necessary. This discovery represents an amalgamation of sophisticatedly temporal and spatial shielding mode conferring self-resistance in antibiotic biosynthesis from Gram-positive bacteria.

Sign in / Sign up

Export Citation Format

Share Document