Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2010-6-25
pubmed:abstractText
Thiolase (acetyl-coenzyme A [CoA] acetyltransferase, E.C. 2.3.1.19) from Clostridium acetobutylicum ATCC 824 has been purified 70-fold to homogeneity. Unlike the thiolase in Clostridium pasteurianum, this thiolase has high relative activity throughout the physiological range of internal pH of 5.5 to 7.0, indicating that change in internal pH during acid production is not an important factor in the regulation of this thiolase. In the condensation direction, the thiolase is inhibited by micromolar levels of CoA, and this may be an important factor in modulating the net condensation of acetyl-CoA to acetoacetyl-CoA. Other cofactors and metabolites that were tested and shown to be inhibitors are ATP and butyryl-CoA. The native enzyme consists of four 44,000-molecular-weight subunits. The kinetic binding mechanism is ping-pong. The K(m) value for acetyl-CoA is 0.27 mM at 30 degrees C and pH 7.4. The K(m) values for sulfhydryl-CoA and acetoacetyl-CoA are, respectively, 0.0048 and 0.032 mM at 30 degrees C and pH 8.0. The active site apparently contains a sulfhydryl group, but unlike other thiolases, this thiolase is relatively stable in the presence of 5,5'-dithiobis(2-nitrobenzoic acid). Studies of thiolase specific activity under various types of continuous fermentations show that regulation of this enzyme at both the genetic and enzyme levels is important.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-1103739, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-14907713, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-23736, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-240336, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-2857719, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-2878927, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-2883931, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-3540574, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-4062485, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-4083872, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-4158310, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-4198758, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-4723225, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-5432063, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-6114098, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-6149704, http://linkedlifedata.com/resource/pubmed/commentcorrection/16347774-6956900
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Nov
pubmed:issn
0099-2240
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2717-22
pubmed:dateRevised
2010-9-20
pubmed:year
1988
pubmed:articleTitle
Thiolase from Clostridium acetobutylicum ATCC 824 and Its Role in the Synthesis of Acids and Solvents.
pubmed:affiliation
Department of Chemical Engineering and Department of Biochemistry, Rice University, Houston, Texas 77251.
pubmed:publicationType
Journal Article