Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2004-5-11
pubmed:abstractText
Electronic absorption and resonance Raman spectroscopies have been applied to study the ferric and ferrous forms, and fluoride complexes of the Tyr249Phe and Met275Ile variants of the recombinant catalase-peroxidase (KatG) from the cyanobacterium Synechocystis PCC 6803. Both crystal structures and mass spectrometric analysis demonstrated that Tyr249 and Met275 are part of a novel KatG-specific covalent adduct including in addition a conserved tryptophan. Its role is not well established, but it has been shown to be essential for the catalase activity. In the present work we investigate the effect of mutation on the protein stability and ligand binding. The results clearly show that mutation weakens the heme binding to the protein, giving rise to a partial conversion from the 5-coordinate high spin of the wild-type protein to 6-coordinate low-spin heme. An internal ligand binds the heme iron on the distal side as a consequence of protein destabilization and partially prevents the binding of external ligand such as fluoride. The results are compared with those previously reported for the Trp122Ala and Trp122Phe variants.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0006-3525
pubmed:author
pubmed:copyrightInfo
Copyright 2004 Wiley Periodicals, Inc. Biopolymers, 2004
pubmed:issnType
Print
pubmed:volume
74
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
46-50
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15137092-Catalase, pubmed-meshheading:15137092-Crystallography, X-Ray, pubmed-meshheading:15137092-Cyanobacteria, pubmed-meshheading:15137092-Electrons, pubmed-meshheading:15137092-Fluorides, pubmed-meshheading:15137092-Haloarcula, pubmed-meshheading:15137092-Heme, pubmed-meshheading:15137092-Hydrogen, pubmed-meshheading:15137092-Iron, pubmed-meshheading:15137092-Ligands, pubmed-meshheading:15137092-Mass Spectrometry, pubmed-meshheading:15137092-Methionine, pubmed-meshheading:15137092-Models, Molecular, pubmed-meshheading:15137092-Mutagenesis, pubmed-meshheading:15137092-Mutagenesis, Site-Directed, pubmed-meshheading:15137092-Mutation, pubmed-meshheading:15137092-Peroxidase, pubmed-meshheading:15137092-Recombinant Proteins, pubmed-meshheading:15137092-Spectrophotometry, pubmed-meshheading:15137092-Spectrum Analysis, Raman, pubmed-meshheading:15137092-Tryptophan, pubmed-meshheading:15137092-Tyrosine
pubmed:articleTitle
Manipulating the covalent link between distal side tryptophan, tyrosine, and methionine in catalase-peroxidases: an electronic absorption and resonance Raman study.
pubmed:affiliation
Dipartimento di Chimica, Universita' di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't