Document Detail


Structure and function in galactosyltransferase. Sequence locations of alpha-lactalbumin binding site, thiol groups, and disulfide bond.
MedLine Citation:
PMID:  1898734     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The region(s) of bovine galactosyltransferase that interacts with the lactose synthase regulatory protein alpha-lactalbumin was investigated using trace 3H acetylation to probe the effects of alpha-lactalbumin on the reactivities of the individual amino groups of galactosyltransferase. In the presence of Mn2+, alpha-lactalbumin was found to reduce the reactivities of lysines 93 and 181 and to increase the reactivities of one or more of lysines 230, 237, and 241. The addition of N-acetylglucosamine (20 mM), which enhances complex formation between the two proteins, did not significantly alter the pattern of perturbation. These results indicate that the NH2-terminal region of the catalytic domain of galactosyltransferase, and possibly part of the proline-rich "stem" region, is affected by the association with alpha-lactalbumin and is therefore implicated in the binding of acceptor substrates. In a separate study only cysteines 176, 266, and 342 of galactosyltransferase were found to react with [3H]iodoacetic acid under denaturing conditions. From their lack of reactivity it is deduced that the remaining two cysteines, residues 134 and 247, are joined in a disulfide linkage. From these results and those of a previous study of UDP-galactose binding (Yadav, S., and Brew, K. (1990) J. Biol. Chem. 265, 14163-14169) it appears that the soluble form of galactosyltransferase is composed of two domains, the NH2-terminal 150 residues containing the Cys134-Cys247 disulfide bond, which functions in alpha-lactalbumin and acceptor binding, and the COOH-terminal region, which is involved in UDP-galactose binding.
Authors:
S P Yadav; K Brew
Related Documents :
21477074 - Alpha-1-antitrypsin is produced by human neutrophil granulocytes and their precursors a...
15368574 - Disaccharide mimetics of the aminoglycoside antibiotic neamine.
11463354 - Knockout of mouse beta 1,4-galactosyltransferase-1 gene results in a dramatic shift of ...
19753484 - Alpha-n-acetylglucosamine-linked o-glycans of sialoglycoproteins (tc-mucins) from trypa...
15686894 - Carbonic anhydrase inhibitors. inhibition of the transmembrane isozyme xii with sulfona...
9827994 - Solution structures of stromelysin complexed to thiadiazole inhibitors.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  266     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  1991 Jan 
Date Detail:
Created Date:  1991-02-12     Completed Date:  1991-02-12     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  698-703     Citation Subset:  IM    
Affiliation:
Department of Biochemistry and Molecular Biology, University of Miami, Florida 33136.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Amino Acid Sequence
Amino Acids / chemistry
Animals
Binding Sites
Cattle
Chromatography, High Pressure Liquid
Cysteine / metabolism
Disulfides / metabolism
Galactosyltransferases / metabolism*
Lactalbumin / metabolism*
Molecular Sequence Data
Structure-Activity Relationship
Sulfhydryl Compounds / metabolism*
Grant Support
ID/Acronym/Agency:
GM21363/GM/NIGMS NIH HHS
Chemical
Reg. No./Substance:
0/Amino Acids; 0/Disulfides; 0/Sulfhydryl Compounds; 52-90-4/Cysteine; 9013-90-5/Lactalbumin; EC 2.4.1.-/Galactosyltransferases

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


Previous Document:  Functional limits of conformation, hydrophobicity, and steric constraints in prokaryotic signal pept...
Next Document:  Sulfation of Tyr1680 of human blood coagulation factor VIII is essential for the interaction of fact...