Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-12-13
pubmed:abstractText
A beta-primeverosidase from tea (Camellia sinensis) plants is a unique disaccharide-specific glycosidase, which hydrolyzes aroma precursors of beta-primeverosides (6-O-beta-D-xylopyranosyl-beta-D-glucopyranosides) to liberate various aroma compounds, and the enzyme is deeply concerned with the floral aroma formation in oolong tea and black tea during the manufacturing process. The beta-primeverosidase was purified from fresh leaves of a cultivar for green tea (C. sinensis var sinensis cv Yabukita), and its partial amino acid sequences were determined. The beta-primeverosidase cDNA has been isolated from a cDNA library of cv Yabukita using degenerate oligonucleotide primers. The cDNA insert encodes a polypeptide consisting of an N-terminal signal peptide of 28 amino acid residues and a 479-amino acid mature protein. The beta-primeverosidase protein sequence was 50% to 60% identical to beta-glucosidases from various plants and was classified in a family 1 glycosyl hydrolase. The mature form of the beta-primeverosidase expressed in Escherichia coli was able to hydrolyze beta-primeverosides to liberate a primeverose unit and aglycons, but did not act on 2-phenylethyl beta-D-glucopyranoside. These results indicate that the beta-primeverosidase selectively recognizes the beta-primeverosides as substrates and specifically hydrolyzes the beta-glycosidic bond between the disaccharide and the aglycons. The stereochemistry for enzymatic hydrolysis of 2-phenylethyl beta-primeveroside by the beta-primeverosidase was followed by (1)H-nuclear magnetic resonance spectroscopy, revealing that the enzyme hydrolyzes the beta-primeveroside by a retaining mechanism. The roles of the beta-primeverosidase in the defense mechanism in tea plants and the floral aroma formation during tea manufacturing process are also discussed.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10425149, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10540751, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10639071, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10652285, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10669009, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10688132, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10923813, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10948259, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-10975500, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11087494, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11092916, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11308343, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11324911, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11607516, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11826969, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11842175, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-11960742, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-12036053, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-13717574, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-13979463, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-1586156, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-16652959, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-16652960, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-16665903, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-16667431, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-16667728, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-1692672, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-2468132, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-3714490, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7480328, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7522061, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7763947, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7765491, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7766881, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-7986074, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8381877, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8535788, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8687420, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8704326, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8722087, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8768320, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8939899, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-8987857, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-9218354, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-9360324, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-9536065, http://linkedlifedata.com/resource/pubmed/commentcorrection/12481100-9852062
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
130
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2164-76
pubmed:dateRevised
2010-9-14
pubmed:meshHeading
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