Document Detail


Locating the Binding Sites of Folic Acid with Milk α- and β-Caseins.
MedLine Citation:
PMID:  22103859     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
We located the binding sites of folic acid with milk α- and β-caseins at physiological conditions, using constant protein concentration and various folic acid contents. FTIR, UV-visible and fluorescence spectroscopic methods as well as molecular modeling were used to analyse folic acid binding sites, the binding constant and the effect of folic acid interaction on the stability and conformation of caseins. Structural analysis showed that folic acid binds caseins via both hydrophilic and hydrophobic contacts with overall binding constants of Kfolic -α--caseins = 4.8 (± 0.6) x 104 M-1 and Kfolic acid-β-caseins = 7.0 (± 0.9) x 104 M-1. The number of bound acid molecules per protein was 1.5 (±0.4) for α-casein and 1.4 (±0.3) for β-casein complexes. Molecular modeling showed different binding sites for folic acid on α- and β-caseins. The participation of several amino acids in folic acid-protein complexes was observed, which stabilized by hydrogen bonding network and the free binding energy of -7.7 kcal/mol (acid-α-casein) and -8.1 kcal/mol (acid-β-casein). Folic acid complexation altered protein secondary structure by reduction of α-helix from 35% (free α-casein) to 33% (acid-complex) and 32% ( free β-casein) to 26% (acid-complex) indicating a partial protein destabilization. Caseins might act as carriers for transportation of folic acid to target molecules.
Authors:
Philippe- Bourassa; Heidar-Ali Tajmir-Riahi
Related Documents :
6814229 - Sulfur balances in intravenously fed infants: effects of cysteine supplementation.
4071539 - Glycosaminoglycans in brush border membranes from rabbit small intestine.
7414609 - Glycoconjugates (glycosaminoglycans and glycoproteins) and glycogen in the human cervix...
10022789 - Hydroxyapatite-collagen-hyaluronic acid composite.
10482449 - A synthetic heparan sulfate pentasaccharide, exclusively containing l-iduronic acid, di...
7100629 - The interaction of tumor localizing porphyrins with collagen and elastin.
4017539 - Changes in the fatty acid composition of phospholipids from turbot (scophthalmus maximu...
3559989 - Spinal and supraspinal components of gabaergic inhibition of the micturition reflex in ...
22061169 - Fatty acid profiles in three stress genotypes of swine and relationships with performan...
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2011-11-21
Journal Detail:
Title:  The journal of physical chemistry. B     Volume:  -     ISSN:  1520-5207     ISO Abbreviation:  -     Publication Date:  2011 Nov 
Date Detail:
Created Date:  2011-11-22     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101157530     Medline TA:  J Phys Chem B     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

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


Previous Document:  Cytochromes P450 Catalyze Both Steps of the Major Pathway of Clopidogrel Bioactivation Whereas Parao...
Next Document:  Yellowish discoloration of dialyzer.