Search results for "LuxR"
showing 3 items of 3 documents
Role of secondary metabolites in the biocontrol activity of Pseudomonas corrugata and Pseudomonas mediterranea
2017
In this study, the Pseudomonas corrugata strain CFBP 5454 and the P. mediterranea strain CFBP 5447 were shown to produce diffusible compounds that inhibit the in vitro growth of plant pathogenic fungi and bacteria and antifungal volatile compounds. In addition, both bacterial strains were found to produce cyanide. Mutant derivatives in LuxR transcriptional regulators, i.e. P. corrugata GL2 (pcoR mutant) and GLRFIA (rfiA mutant), and P. mediterranea PSMER (pmeR mutant) and PSRFIA (rfiA mutant) impaired in cyclic lipopeptide (CLP) production, showed a diffusible compound-mediated reduced activity, depending on the biocontrol strain, challenge microorganism and culture medium. The volatile com…
Complex Regulatory Networks Governing Production of the Glycopeptide A40926
2018
Glycopeptides (GPAs) are an important class of antibiotics, with vancomycin and teicoplanin being used in the last 40 years as drugs of last resort to treat infections caused by Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus. A few new GPAs have since reached the market. One of them is dalbavancin, a derivative of A40926 produced by the actinomycete Nonomuraea sp. ATCC 39727, recently classified as N. gerenzanensis. This review summarizes what we currently know on the multilevel regulatory processes governing production of the glycopeptide A40926 and the different approaches used to increase antibiotic yields. Some nutrients, e.g., valine, l-glutamine and mal…
Regulation of physiological differentiation in Nonomuraea sp. ATCC 39727
2014
The Actinomycete Nonomuraea produces the glycopeptide A40926, precursor of dalbavancin, a novel lipoglycopeptide homologous to vancomycin that could be used against emerging resistant Gram-positive bacteria. The A40926 biosynthetic gene cluster (dbv), which consists of 37 genes, encodes two regulators, Dbv3 (LuxR-like) and Dbv4 (StrR-like), as well as the response regulator (Dbv6) and the sensor-kinase (Dbv22) of a putative two-component system. Previous work demonstrated a positive role of Dbv4 in antibiotic production by activating the transcription of 13 dbv genes; up to now no role was assigned to Dbv3, Dbv6 and Dbv22. In addition, an IclR-like protein is thought to be involved in dbv4 …