Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-6-29
pubmed:abstractText
An elicitor-inducible sesquiterpene cyclase, which catalyzes the conversion of farnesyl diphosphate to 5-epi-aristolochene (IM Whitehead, DR Threlfall, DF Ewing [1989] Phytochemistry 28:775-779) and representing a committed step in the phytoalexin biosynthetic pathway in tobacco, was purified by a combination of hydrophobic interaction, anion exchange, hydroxylapatite, and chromatofocusing chromatography. From 2 kilograms of elicited tobacco (Nicotiana tabacum) cells, approximately 500 micrograms of cyclase protein was purified, representing greater than a 130-fold increase in the specific activity of the enzyme and a 4% recovery of the starting activity. The purified enzyme resolved as two major polypeptides of 60 and 62 kilodaltons by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Biochemical characterization of the enzyme activity included an absolute requirement for magnesium, an isoelectric point of 4.5 to 4.9, and a K(m) for farnesyl diphosphate of 2 to 5 micromolar. The purified cyclase protein was used to generate mouse polyclonal antibodies which efficiently inhibited cyclase activity in an in vitro assay. Electrophoresis of extracts from elicitor-treated cells or purified cyclase enzyme on native polyacrylamide gels separated the cyclase enzyme into four polypeptides as shown by immunoblot analysis using poly- and monoclonal antibodies. Proportionate cyclase enzyme activity comigrated with those polypeptides. No cyclase polypeptides were detectable in extracts of control cells by immunoblot analysis. However, immunoblot analysis of proteins from elicitor-treated cells using four independent monoclonal antibody lines and the polyclonal antibodies detected the same polypeptides, regardless of whether the proteins were separated by native or SDS-PAGE. The results suggest an induction of multiple cyclase polypeptides in elicitor-treated cells resulting from either the expression of multiple genes or multiple post-translational processing events.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16659566, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16660566, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16665452, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16665722, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16665815, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-16666457, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-2414646, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-2544140, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-3038029, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-3355155, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-3579312, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-3800398, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-3985625, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-5432063, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-6191328, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-6206159, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-6486812, http://linkedlifedata.com/resource/pubmed/commentcorrection/16667432-942051
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
May
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
182-7
pubmed:dateRevised
2010-9-15
pubmed:year
1990
pubmed:articleTitle
Purification and characterization of an inducible sesquiterpene cyclase from elicitor-treated tobacco cell suspension cultures.
pubmed:affiliation
Plant Physiology/Biochemistry Program, Agronomy Department, University of Kentucky, Lexington, Kentucky 40546-0091.
pubmed:publicationType
Journal Article