Identification of RimR2 as a positive pathway-specific regulator of rimocidin biosynthesis in Streptomyces rimosus M527

© 2023. The Author(s)..

BACKGROUND: Streoptomyces rimosus M527 is a producer of the polyene macrolide rimocidin which shows activity against various plant pathogenic fungi. Notably, the regulatory mechanisms underlying rimocidin biosynthesis are yet to be elucidated.

RESULTS: In this study, using domain structure and amino acid alignment and phylogenetic tree construction, rimR2, which located in the rimocidin biosynthetic gene cluster, was first found and identified as a larger ATP-binding regulators of the LuxR family (LAL) subfamily regulator. The rimR2 deletion and complementation assays were conducted to explore its role. Mutant M527-ΔrimR2 lost its ability to produce rimocidin. Complementation of M527-ΔrimR2 restored rimocidin production. The five recombinant strains, M527-ER, M527-KR, M527-21R, M527-57R, and M527-NR, were constructed by overexpressing rimR2 gene using the promoters permE*, kasOp*, SPL21, SPL57, and its native promoter, respectively, to improve rimocidin production. M527-KR, M527-NR, and M527-ER exhibited 81.8%, 68.1%, and 54.5% more rimocidin production, respectively, than the wild-type (WT) strain, while recombinant strains M527-21R and M527-57R exhibited no obvious differences in rimocidin production compared with the WT strain. RT-PCR assays revealed that the transcriptional levels of the rim genes were consistent with the changes in rimocidin production in the recombinant strains. Using electrophoretic mobility shift assays, we confirmed that RimR2 can bind to the promoter regions of rimA and rimC.

CONCLUSION: A LAL regulator RimR2 was identified as a positive specific-pathway regulator of rimocidin biosynthesis in M527. RimR2 regulates the rimocidin biosynthesis by influencing the transcriptional levels of rim genes and binding to the promoter regions of rimA and rimC.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:22

Enthalten in:

Microbial cell factories - 22(2023), 1 vom: 21. Feb., Seite 32

Sprache:

Englisch

Beteiligte Personen:

Li, Huijie [VerfasserIn]
Hu, Yefeng [VerfasserIn]
Zhang, Yongyong [VerfasserIn]
Ma, Zheng [VerfasserIn]
Bechthold, Andreas [VerfasserIn]
Yu, Xiaoping [VerfasserIn]

Links:

Volltext

Themen:

72LLC1Q06O
Bacterial Proteins
Journal Article
LAL regulator
Polyenes
RimR2
Rimocidin
Streptomyces rimosus

Anmerkungen:

Date Completed 24.02.2023

Date Revised 25.02.2023

published: Electronic

Citation Status MEDLINE

doi:

10.1186/s12934-023-02039-9

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM353163821