Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2005-9-12
pubmed:abstractText
Apocytochrome c interacts with two copolymers: poly(isobutylene-alt-maleic acid) (PIMA) and poly(1-tetradecene-alt-maleic acid) (PTMA). The interaction leads to apocytochrome c, a conformational change from random coil to alpha-helical structure. The alpha-helix content is influenced by the copolymer concentration, the length of alkyl chain of the copolymers, and pH of the medium. The electrostatic attraction between the copolymer and protein is an indispensable factor for the folding of the protein at acid pH. The hydrophobic interaction is an important factor over the entire pH range, especially when both the copolymer and protein carry negative charges at alkaline pH. The electrostatic and hydrophobic attractions between the copolymer and protein exclude water molecules, promoting the formation of hydrogen bonds within the helical structure. On the other hand, the hydrogen bonds formed between the ionized carboxyl of the copolymer and the amide of the protein partly restrain the formation of hydrogen bonds within the helical structure when the copolymer concentration is higher at pH 6.5 and 10.5.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1525-7797
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2748-55
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:16153115-Alkenes, pubmed-meshheading:16153115-Animals, pubmed-meshheading:16153115-Carbon, pubmed-meshheading:16153115-Circular Dichroism, pubmed-meshheading:16153115-Cytochromes c, pubmed-meshheading:16153115-Dose-Response Relationship, Drug, pubmed-meshheading:16153115-Horses, pubmed-meshheading:16153115-Hydrogen Bonding, pubmed-meshheading:16153115-Hydrogen-Ion Concentration, pubmed-meshheading:16153115-Ions, pubmed-meshheading:16153115-Maleates, pubmed-meshheading:16153115-Models, Chemical, pubmed-meshheading:16153115-Polymers, pubmed-meshheading:16153115-Potentiometry, pubmed-meshheading:16153115-Protein Conformation, pubmed-meshheading:16153115-Protein Structure, Secondary, pubmed-meshheading:16153115-Quaternary Ammonium Compounds, pubmed-meshheading:16153115-Spectrometry, Fluorescence, pubmed-meshheading:16153115-Spectrophotometry, pubmed-meshheading:16153115-Static Electricity, pubmed-meshheading:16153115-Tryptophan, pubmed-meshheading:16153115-Ultraviolet Rays
pubmed:articleTitle
Structural transformation of apocytochrome c induced by alternating copolymers of maleic acid and alkene.
pubmed:affiliation
Department of Macromolecular Science and Key Laboratory of Molecular Engineering of Polymer, Fudan University, Shanghai 200433, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't