Source:http://linkedlifedata.com/resource/pubmed/id/11380251
Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
22
|
pubmed:dateCreated |
2001-5-30
|
pubmed:abstractText |
The structural changes in the heme macrocycle and substituents caused by binding of Ca(2+) to the diheme cytochrome c peroxidase from Paracoccus pantotrophus were clarified by resonance Raman spectroscopy of the inactive fully oxidized form of the enzyme. The changes in the macrocycle vibrational modes are consistent with a Ca(2+)-dependent increase in the out-of-plane distortion of the low-potential heme, the proposed peroxidatic heme. Most of the increase in out-of-plane distortion occurs when the high-affinity site I is occupied, but a small further increase in distortion occurs when site II is also occupied by Ca(2+) or Mg(2+). This increase in the heme distortion explains the red shift in the Soret absorption band that occurs upon Ca(2+) binding. Changes also occur in the low-frequency substituent modes of the heme, indicating that a structural change in the covalently attached fingerprint pentapeptide of the LP heme occurs upon Ca(2+) binding to site I. These structural changes may lead to loss of the sixth ligand at the peroxidatic heme in the semireduced form of the enzyme and activation.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Jun
|
pubmed:issn |
0006-2960
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
5
|
pubmed:volume |
40
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
6570-9
|
pubmed:dateRevised |
2006-11-15
|
pubmed:meshHeading |
pubmed-meshheading:11380251-Binding Sites,
pubmed-meshheading:11380251-Calcium,
pubmed-meshheading:11380251-Cytochrome-c Peroxidase,
pubmed-meshheading:11380251-Heme,
pubmed-meshheading:11380251-Hydrogen-Ion Concentration,
pubmed-meshheading:11380251-Oxidation-Reduction,
pubmed-meshheading:11380251-Paracoccus,
pubmed-meshheading:11380251-Peptide Fragments,
pubmed-meshheading:11380251-Protein Conformation,
pubmed-meshheading:11380251-Spectrum Analysis, Raman,
pubmed-meshheading:11380251-Thermodynamics
|
pubmed:year |
2001
|
pubmed:articleTitle |
Calcium-dependent conformation of a heme and fingerprint peptide of the diheme cytochrome c peroxidase from Paracoccus pantotrophus.
|
pubmed:affiliation |
Centro de Química Fina e Biotecnologia, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2825 Monte de Caparica, Portugal.
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, Non-P.H.S.
|