Resonance energy transfer between tryptophanyl residues and the apolar fluorescent dye 1-anilino-8-naphthalene sulfonate (ANS) occurs when the fluorophore is bound to native folded sperm whale apomyoglobin. The individual transfer contribution of the two tryptophanyl residues (W7 and W14, both located on the A-helix of the protein) was resolved by measuring the tryptophan-ANS transfer efficiency for the ANS-apomyoglobin complexes formed by wild-type protein and protein mutants containing one or no tryptophanyl residues, i.e. W7F, W14F and W7YW14F. The transfer efficiency of W14 residue was found to be higher than that of W7, thus indicating that W14 acts as the main energy donor in the ANS-apomyoglobin complex. This suggests that the plane containing the anilinonaphthalene ring of the extrinsic fluorophore has a spatial orientation similar to that of W14 and, hence, to the heme group in the holoprotein.

Download full-text PDF

Source
http://dx.doi.org/10.1562/0031-8655(2002)076<0381:rotafe>2.0.co;2DOI Listing

Publication Analysis

Top Keywords

tryptophanyl residues
12
energy transfer
8
transfer efficiency
8
transfer
5
resolution tryptophan-ans
4
tryptophan-ans fluorescence
4
fluorescence energy
4
transfer apomyoglobin
4
apomyoglobin site-directed
4
site-directed mutagenesis
4

Similar Publications

Divergent Metabolism of -l-Trp-l-Leu in by Hydroxylation and Nucleobase Transfer with Two Cytochrome P450 Enzymes.

J Nat Prod

December 2024

Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch-Straße 4, Marburg 35037, Germany.

A three-gene cluster from was proven to be responsible for the formation of -l-Trp-l-Leu (cWL) derivatives. An strain harboring the cyclodipeptide synthase (CDPS) gene produced cWL. Expression of the whole cluster or genes of various combinations in revealed different metabolites of cWL by two cytochrome P450 enzymes.

View Article and Find Full Text PDF

Many bacteria encode multiple toxin-antitoxin (TA) systems targeting separate, but closely related, cellular functions. The toxin of the system, HipA, is a kinase that inhibits translation via phosphorylation of glutamyl-tRNA synthetase. Enteropathogenic O127:H6 encodes the -like, tripartite TA system; , in which the HipT toxin specifically targets the tryptophanyl-tRNA synthetase, TrpS.

View Article and Find Full Text PDF

Landscape descriptions provide a framework for identifying functionally significant dynamic linkages in proteins but cannot supply details. Rate measurements of combinatorial mutations can implicate dynamic linkages in catalysis. A major difficulty is filtering dynamic linkages from the vastly more numerous static interactions that stabilize domain folding.

View Article and Find Full Text PDF

An asymmetric structure of bacterial TrpRS supports the half-of-the-sites catalytic mechanism and facilitates antimicrobial screening.

Nucleic Acids Res

May 2023

Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery and Research Center for Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, Guangdong510006, China.

Tryptophanyl-tRNA synthetase (TrpRS) links tryptophan to tRNATrp, thereby playing an indispensable role in protein translation. Unlike most class I aminoacyl-tRNA synthetases (AARSs), TrpRS functions as a homodimer. Herein, we captured an 'open-closed' asymmetric structure of Escherichia coli TrpRS (EcTrpRS) with one active site occupied by a copurified intermediate product and the other remaining empty, providing structural evidence for the long-discussed half-of-the-sites reactivity of bacterial TrpRS.

View Article and Find Full Text PDF

The potential antimicrobial compound Chuangxinmycin (CXM) targets the tryptophanyl-tRNA synthetase (TrpRS) of both Gram-negative and Gram-positive bacteria. However, the specific steric recognition mode and interaction mechanism between CXM and TrpRS is unclear. Here, we studied this interaction using recombinant GsTrpRS from Geobacillus stearothermophilus by X-ray crystallography and molecular dynamics (MD) simulations.

View Article and Find Full Text PDF

Want 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!