Linked Life Data

11473129

Source:http://linkedlifedata.com/resource/pubmed/id/11473129

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
40
pubmed:dateCreated
2001-10-1
pubmed:databankReference
pubmed:abstractText
Klebsiella pneumoniae is presently unique among bacterial species in its ability to metabolize not only sucrose but also its five linkage-isomeric alpha-d-glucosyl-d-fructoses: trehalulose, turanose, maltulose, leucrose, and palatinose. Growth on the isomeric compounds induced a protein of molecular mass approximately 50 kDa that was not present in sucrose-grown cells and which we have identified as an NAD(+) and metal ion-dependent 6-phospho-alpha-glucosidase (AglB). The aglB gene has been cloned and sequenced, and AglB (M(r) = 49,256) has been purified from a high expression system using the chromogenic p-nitrophenyl alpha-glucopyranoside 6-phosphate as substrate. Phospho-alpha-glucosidase catalyzed the hydrolysis of a wide variety of 6-phospho-alpha-glucosides including maltose-6'-phosphate, maltitol-6-phosphate, isomaltose-6'-phosphate, and all five 6'-phosphorylated isomers of sucrose (K(m) approximately 1-5 mm) yet did not hydrolyze sucrose-6-phosphate. By contrast, purified sucrose-6-phosphate hydrolase (M(r) approximately 53,000) hydrolyzed only sucrose-6-phosphate (K(m) approximately 80 microm). Differences in molecular shape and lipophilicity potential between sucrose and its isomers may be important determinants for substrate discrimination by the two phosphoglucosyl hydrolases. Phospho-alpha-glucosidase and sucrose-6-phosphate hydrolase exhibit no significant homology, and by sequence-based alignment, the two enzymes are assigned to Families 4 and 32, respectively, of the glycosyl hydrolase superfamily. The phospho-alpha-glucosidase gene (aglB) lies adjacent to a second gene (aglA), which encodes an EII(CB) component of the phosphoenolpyruvate-dependent sugar:phosphotransferase system. We suggest that the products of the two genes facilitate the phosphorylative translocation and subsequent hydrolysis of the five alpha-d-glucosyl-d-fructoses by K. pneumoniae.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37415-25
pubmed:dateRevised
2008-7-2
pubmed:meshHeading
pubmed-meshheading:11473129-Amino Acid Sequence, pubmed-meshheading:11473129-Bacterial Proteins, pubmed-meshheading:11473129-Base Sequence, pubmed-meshheading:11473129-Biological Transport, pubmed-meshheading:11473129-Cloning, Molecular, pubmed-meshheading:11473129-DNA, Bacterial, pubmed-meshheading:11473129-Escherichia coli, pubmed-meshheading:11473129-Fructose, pubmed-meshheading:11473129-Glycoside Hydrolases, pubmed-meshheading:11473129-Hydrolysis, pubmed-meshheading:11473129-Klebsiella pneumoniae, pubmed-meshheading:11473129-Metals, pubmed-meshheading:11473129-Models, Molecular, pubmed-meshheading:11473129-Molecular Sequence Data, pubmed-meshheading:11473129-Protein Isoforms, pubmed-meshheading:11473129-Sequence Analysis, DNA, pubmed-meshheading:11473129-Sequence Homology, Amino Acid, pubmed-meshheading:11473129-Substrate Specificity, pubmed-meshheading:11473129-Sucrose, pubmed-meshheading:11473129-alpha-Glucosidases, pubmed-meshheading:11473129-beta-Fructofuranosidase
pubmed:year
2001
pubmed:articleTitle
Metabolism of sucrose and its five linkage-isomeric alpha-D-glucosyl-D-fructoses by Klebsiella pneumoniae. Participation and properties of sucrose-6-phosphate hydrolase and phospho-alpha-glucosidase.
pubmed:affiliation
Microbial Biochemistry and Genetics Unit, Oral Infection and Immunity Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892, USA. jthompson@dir.nidcr.noh.gov
pubmed:publicationType
Journal Article