The fluorescence studies of E. coli porin OmpF at pH 7.5 were carried out using excitation at 280 and 305 nm. Similar studies were performed in presence of a denaturant (urea) and a quencher (KI). Results show that both the tryptophans present in OmpF (residue numbers 61 and 214) contribute to fluorescence at 280 nm excitation, whereas only one residue shows fluorescence emission when excited at 305 nm. Based on these findings and the available crystal structure, it is speculated that tryptophan 61 of OmpF is selectively excited at 305 nm. The present studies point out some interesting features of the tryptophan microenvironments in OmpF.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1080/15216549700202561 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Interaction of Tryptophan- and Arginine-Rich Antimicrobial Peptide with Outer Membrane-A Molecular Simulation Approach.
Int J Mol Sci
January 2023
Department of Life and Environmental Physics, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, 077125 Magurele, Romania.
A short antimicrobial peptide (AMP), rich in tryptophan and arginine (P6-HRWWRWWRR-NH2), was used in molecular dynamics (MD) simulations to investigate the interaction between AMPs and lipopolysaccharides (LPS) from two outer membrane (OM) membrane models. The OM of Gram-negative bacteria is an asymmetric bilayer, with the outer layer consisting exclusively of lipopolysaccharide molecules and the lower leaflet made up of phospholipids. The mechanisms by which short AMPs permeate the OM of Gram-negative bacteria are not well understood at the moment.
View Article and Find Full Text PDFFunctional and structural characterization of Hyp730, a highly conserved and dormancy-specific hypothetical membrane protein.
Microbiologyopen
January 2021
Department of Biology and Biochemistry, University of Houston, Houston, TX, USA.
Article Synopsis
- * Specifically, the hypothetical membrane protein Hyp730 from M. luteus is upregulated during dormancy, yet its function has not been previously characterized, despite its potential role in energy-saving during stressful conditions.
- * Extensive analysis has shown Hyp730 is a non-essential, double-pass membrane protein with a conserved structure among Actinobacteria, warranting further investigation into its role under stress.
Engineering a Novel Porin OmpGF Via Strand Replacement from Computational Analysis of Sequence Motif.
Biochim Biophys Acta Biomembr
July 2017
Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60612, United States. Electronic address:
β-Barrelmembrane proteins (βMPs) form barrel-shaped pores in the outer membrane of Gram-negative bacteria, mitochondria, and chloroplasts. Because of the robustness of their barrel structures, βMPs have great potential as nanosensors for single-molecule detection. However, natural βMPs currently employed have inflexible biophysical properties and are limited in their pore geometry, hindering their applications in sensing molecules of different sizes and properties.
View Article and Find Full Text PDFOmpC-like porin from outer membrane of Yersinia enterocolitica: molecular structure and functional activity.
Biochemistry (Mosc)
May 2013
Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, pr. 100 let Vladivostoku 159, 690022 Vladivostok, Russia.
OmpC-like porin was isolated from the outer membrane (OM) of Yersinia enterocolitica cultured at 37°C (the "warm" variant) and its physicochemical and functional properties were studied. The amino acid sequence of OmpC porin was established, and the primary structure and transmembrane topology of this protein were analyzed in comparison with the OmpF porin isolated from Y. enterocolitica cultured at 6°C (the "cold" variant).
View Article and Find Full Text PDFEffect of phenol-induced changes in lipid composition on conformation of OmpF-like porin of Yersinia pseudotuberculosis.
FEBS Lett
July 2013
Department of Biochemistry, Microbiology and Biotechnology, Far Eastern Federal University, Sukhanov St., 8, Vladivostok 690600, Russia.
The present work aimed to compare the effects of different lysophosphatidylethanolamine (LPE) content in lipids derived from Yersinia pseudotuberculosis cells exposed and not exposed to phenol on the conformation of OmpF-like porin of these bacteria. Differential scanning calorimetry and intrinsic protein fluorescence showed that the 2.5-fold increase of LPE content and the corresponding increase in the phase transition temperature of bacterial lipids were accompanied by enhanced protein thermostability.
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!