Linked Life Data

1354172

Source:http://linkedlifedata.com/resource/pubmed/id/1354172

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-9-16
pubmed:abstractText
Site-directed mutagenesis experiments designed to identify the active site of Bacillus licheniformis endo-beta-1,3-1,4-D-glucan 4-glucanohydrolase (beta-glucanase) have been performed. Putative catalytic residues were chosen on the basis of sequence similarity analysis to viral and eukaryotic lysozymes. Four mutant enzymes were expressed and purified from recombinant E. coli and their kinetics analysed with barley beta-glucan. Replacement of Glu134 by Gln produced a mutant (E134Q) that retains less than 0.3% of the wild-type activity. The other mutants, D133N, E160Q and D179N, are active but show different kinetic parameters relative to wild-type indicative of their participation in substrate binding and transition-state complex stabilization. Glu134 is essential for activity; it is comprised in a region of high sequence similarity to the active site of T4 lysozyme and matches the position of the general acid catalyst. These results strongly support a lysozyme-like mechanism for this family of Bacillus beta-glucan hydrolases with Glu134 being the essential acid catalyst.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0014-5793
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
308
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
141-5
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Essential catalytic role of Glu134 in endo-beta-1,3-1,4-D-glucan 4-glucanohydrolase from B. licheniformis as determined by site-directed mutagenesis.
pubmed:affiliation
Institut de Biologia Fonamental V, Universitat Autonoma de Barcelona, Bellaterra, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't