Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1987-4-27
pubmed:abstractText
Radiolabeling of human liver alpha-L-fucosidase (alpha-L-fucoside fucohydrolase, EC 3.2.1.51) with [1-3H]conduritol C trans-epoxide revealed that there are four active sites per tetrameric enzyme complex. Solvent isotope effect experiments give evidence for a proton transfer at the rate-limiting step in catalysis. Transglycosylase activity was observed using methanol as an alternative glycone acceptor to produce methyl alpha-L-fucoside, suggesting that alpha-L-fucose is formed when water is the acceptor. Initial burst kinetics experiments suggest that a glycosyl-enzyme intermediate is formed, although the magnitude of the burst is not stoichiometric with the number of active sites. These data, along with previous results, suggest a general acid-general base catalytic mechanism involving double inversion of stereochemistry at C-1 of fucose, as well as the formation of either a covalent glycosyl-enzyme intermediate or a tight ion pair between a charged active-site residue and a hypothetical fucosyl oxocarbonium ion intermediate.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
912
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
132-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Further studies on the catalytic mechanism of human liver alpha-L-fucosidase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.