Document Detail

Atomic resolution crystal structures, EXAFS, and quantum chemical studies of rusticyanin and its two mutants provide insight into its unusual properties.
MedLine Citation:
PMID:  16503647     Owner:  NLM     Status:  MEDLINE    
Rusticyanin from the extremophile Thiobacillus ferrooxidans is a blue copper protein with unusually high redox potential and acid stability. We present the crystal structures of native rusticyanin and of its Cu site mutant His143Met at 1.27 and 1.10 A, respectively. The very high resolution of these structures allows a direct comparison with EXAFS data and with quantum chemical models of the oxidized and reduced forms of the proteins, based upon both isolated and embedded clusters and density functional theory (DFT) methods. We further predict the structure of the Cu(II) form of the His143Met mutant which has been experimentally inaccessible due to its very high redox potential. We also present metrical EXAFS data and quantum chemical calculations for the oxidized and reduced states of the Met148Gln mutant, this protein having the lowest redox potential of all currently characterized mutants of rusticyanin. These data offer new insights into the structural factors which affect the redox potential in this important class of proteins. Calculations successfully predict the structure and the order of redox potentials for the three proteins. The calculated redox potential of H143M ( approximately 400 mV greater than native rusticyanin) is consistent with the failure of readily available chemical oxidants to restore a Cu(II) species of this mutant. The structural and energetic effects of mutating the equatorial cysteine to serine, yet to be studied experimentally, are predicted to be considerable by our calculations.
Mark L Barrett; Ian Harvey; Mahesh Sundararajan; Rajeev Surendran; John F Hall; Mark J Ellis; Michael A Hough; Richard W Strange; Ian H Hillier; S Samar Hasnain
Related Documents :
15579957 - Poly[[bis(pyridine-kappan)copper(ii)]-mu(3)-5-hydroxyisophthalato-kappa3o:o':o''].
11065187 - Cu(ii) and zn(ii) complexes with hyaluronic acid and its sulphated derivative. effect o...
18962587 - Handling of electronic absorption spectra with a desk-top computer-ii calculation of st...
15134727 - Structure of copper(ii) dithiocarbamate mixed-ligand complexes and their photoreactivit...
11258977 - Structure-activity relationships for a large diverse set of natural, synthetic, and env...
7687877 - Two-dimensional rotational-echo double resonance of val1-[1-13c]gly2-[15n]ala3-gramicid...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Biochemistry     Volume:  45     ISSN:  0006-2960     ISO Abbreviation:  Biochemistry     Publication Date:  2006 Mar 
Date Detail:
Created Date:  2006-02-28     Completed Date:  2006-04-28     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370623     Medline TA:  Biochemistry     Country:  United States    
Other Details:
Languages:  eng     Pagination:  2927-39     Citation Subset:  IM    
School of Health and Life Sciences, De Montfort University, The Gateway, Leicester, UK.
Data Bank Information
Bank Name/Acc. No.:
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Azurin / chemistry*,  genetics
Computers, Molecular
Copper / chemistry,  metabolism
Crystallography, X-Ray
Histidine / genetics,  metabolism
Metalloproteins / chemistry
Methionine / genetics,  metabolism
Models, Molecular
Point Mutation
Structure-Activity Relationship
Thiobacillus / metabolism
Reg. No./Substance:
0/Metalloproteins; 0/Solvents; 0/rusticyanin; 12284-43-4/Azurin; 63-68-3/Methionine; 71-00-1/Histidine; 7440-50-8/Copper

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Methane monooxygenase hydroxylase and B component interactions.
Next Document:  Comparison of the binding and reactivity of plant and mammalian peroxidases to indole derivatives by...