Linked Life Data

8344920

Source:http://linkedlifedata.com/resource/pubmed/id/8344920

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
1993-9-7
pubmed:databankReference
pubmed:abstractText
The complete nucleotide sequence of the gene encoding the dual active amylopullulanase of Thermoanaerobacter ethanolicus 39E (formerly Clostridium thermohydrosulfuricum) was determined. The structural gene (apu) contained a single open reading frame 4443 base pairs in length, corresponding to 1481 amino acids, with an estimated molecular weight of 162,780. Analysis of the deduced sequence of apu with sequences of alpha-amylases and alpha-1,6 debranching enzymes enabled the identification of four conserved regions putatively involved in substrate binding and in catalysis. The conserved regions were localized within a 2.9-kilobase pair gene fragment, which encoded a M(r) 100,000 protein that maintained the dual activities and thermostability of the native enzyme. The catalytic residues of amylopullulanase were tentatively identified by using hydrophobic cluster analysis for comparison of amino acid sequences of amylopullulanase and other amylolytic enzymes. Asp597, Glu626, and Asp703 were individually modified to their respective amide form, or the alternate acid form, and in all cases both alpha-amylase and pullulanase activities were lost, suggesting the possible involvement of 3 residues in a catalytic triad, and the presence of a putative single catalytic site within the enzyme. These findings substantiate amylopullulanase as a new type of amylosaccharidase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
268
pubmed:geneSymbol
apu
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16332-44
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Sequencing of the amylopullulanase (apu) gene of Thermoanaerobacter ethanolicus 39E, and identification of the active site by site-directed mutagenesis.
pubmed:affiliation
Department of Biochemistry, Michigan State University, East Lansing 48824.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.