Synthesis of catabolite-sensitive enzymes is repressed in mutants defective in the general proteins (enzyme I and HPr) of the Escherichia coli phosphoenolpyruvate-dependent phosphotransferase system (ptsI and ptsH mutations). To elucidate the mechanism of this phenomenon we constructed isogenic strains carrying pts mutations as well as different lesions of regulation of the lac operon or mutations affecting adenylate cyclase activity (cya mutation) and synthesis of cyclic AMP-receptor protein (crp mutation) Measurements of the differential rate of beta-galactosidase synthesis in these strains showed that the repressive effect of pts mutations was revealed in lac+, lacI, lacOc and cya bacteria, but it was lost in lacP and crp strains. It was concluded that mutational damage to the general components of the phosphoenolpyruvate-dependent phosphotransferase system diminishes activity of the lac promoter. The results obtained led to the conclusion that pts gene products (apparently phospho approximately HPr) are necessary for the initiation of transcription of catabolite-sensitive operons in E. coli.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1432-1033.1978.tb12552.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
MtlD as a therapeutic target for intestinal and systemic bacterial infections.
J Bacteriol
December 2024
Department of Microbiology, The Ohio State University, Columbus, Ohio, USA.
Unlabelled: The ability to treat infections is threatened by the rapid emergence of antibiotic resistance among pathogenic microbes. Therefore, new antimicrobials are needed. Here we evaluate mannitol-1-phosphate 5-dehydrogenase (MtlD) as a potential new drug target.
View Article and Find Full Text PDFStructure and mechanism of a phosphotransferase system glucose transporter.
Nat Commun
September 2024
Institute of Biochemistry and Molecular Medicine, Medical Faculty, University of Bern, Bern, Switzerland.
Glucose is the primary source of energy for many organisms and is efficiently taken up by bacteria through a dedicated transport system that exhibits high specificity. In Escherichia coli, the glucose-specific transporter IICB serves as the major glucose transporter and functions as a component of the phosphoenolpyruvate-dependent phosphotransferase system. Here, we report cryo-electron microscopy (cryo-EM) structures of the glucose-bound IICB protein.
View Article and Find Full Text PDFEngineering PTS-based glucose metabolism for efficient biosynthesis of bacterial cellulose by Komagataeibacter xylinus.
Carbohydr Polym
November 2024
State Key Laboratory of Food Nutrition &Safety, Tianjin University of Science and Technology, Tianjin 300457, PR China; Key Laboratory of Industrial Fermentation Microbiology (Ministry of Education), Tianjin University of Science and Technology, Tianjin 300457, PR China.
Bacterial cellulose (BC) is a renewable biomaterial that has attracted significant attention due to its excellent properties and wide applications. Komagataeibacter xylinus CGMCC 2955 is an important BC-producing strain. It primarily produces BC from glucose while simultaneously generating gluconic acid as a by-product, which acidifies the medium and inhibits BC synthesis.
View Article and Find Full Text PDFAims: This study evaluates the antibacterial characteristics and mechanisms of combined tea polyphenols (TPs), Nisin, and ε-polylysine (PL) against Streptococcus canis, Streptococcus minor, Streptococcus mutans, and Actinomyces oris, common zoonotic pathogens in companion animals.
Methods And Results: Pathogenic strains were isolated from feline oral cavities and assessed using minimum inhibitory concentration (MIC) tests, inhibition zone assays, growth kinetics, and biofilm inhibition studies. Among single agents, PL exhibited the lowest MIC values against all four pathogens.
Maribacter halichondriae sp. nov., isolated from the marine sponge Halichondria panicea, displays features of a sponge-associated life style.
Antonie Van Leeuwenhoek
March 2024
GEOMAR Helmholtz Centre for Ocean Research Kiel, RU Marine Ecology, RD3 Marine Symbioses, Wischhofstraße 1-3, 24148, Kiel, Germany.
A new member of the family Flavobacteriaceae (termed Hal144) was isolated from the marine breadcrumb sponge Halichondria panicea. Sponge material was collected in 2018 at Schilksee which is located in the Kiel Fjord (Baltic Sea, Germany). Phylogenetic analysis of the full-length Hal144 16S rRNA gene sequence revealed similarities from 94.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!