Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2010-6-14
pubmed:abstractText
Inhibition of photosynthesis by heat has been linked to the instability of the ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) chaperone, Rubisco activase. Examination of the recombinant enzyme showed that ADP and ATP protected against inactivation, whereas Mg(2+) promoted inactivation. Heating caused aggregation of Rubisco activase characterized by disruption of secondary structure content and formation of insoluble protein. In contrast, incubation at room temperature without nucleotide caused the active approximately 660 kDa protein to form a soluble, but inactive aggregate of > 2 x 10(6) Da. Circular dichroism (CD) spectroscopy and fluorescence established that structural perturbations in the aggregate did not reduce alpha-helical content significantly. Differences in the thermal stability between wild type and mutant Rubisco activase were observed for the recombinant proteins and when the proteins were expressed in transgenic Arabidopsis. That the sensitivity of these plants to heat differs indicates that the thermal instability of Rubisco activase is a main determinant of the temperature-sensitivity of photosynthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1096-0384
pubmed:author
pubmed:copyrightInfo
Published by Elsevier Inc.
pubmed:issnType
Electronic
pubmed:volume
499
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17-25
pubmed:meshHeading
pubmed-meshheading:20450882-Adenosine Diphosphate, pubmed-meshheading:20450882-Adenosine Triphosphate, pubmed-meshheading:20450882-Arabidopsis, pubmed-meshheading:20450882-Arabidopsis Proteins, pubmed-meshheading:20450882-Circular Dichroism, pubmed-meshheading:20450882-Enzyme Activation, pubmed-meshheading:20450882-Enzyme Stability, pubmed-meshheading:20450882-Hot Temperature, pubmed-meshheading:20450882-Magnesium, pubmed-meshheading:20450882-Mutant Proteins, pubmed-meshheading:20450882-Photosynthesis, pubmed-meshheading:20450882-Plant Proteins, pubmed-meshheading:20450882-Plants, Genetically Modified, pubmed-meshheading:20450882-Protein Denaturation, pubmed-meshheading:20450882-Protein Multimerization, pubmed-meshheading:20450882-Protein Structure, Secondary, pubmed-meshheading:20450882-Recombinant Proteins, pubmed-meshheading:20450882-Ribulose-Bisphosphate Carboxylase, pubmed-meshheading:20450882-Thermodynamics
pubmed:year
2010
pubmed:articleTitle
Structural changes associated with the acute thermal instability of Rubisco activase.
pubmed:affiliation
US Department of Agriculture-Agricultural Research Service, Arid-Land Agricultural Research Center, Maricopa, AZ 85139, USA. csengele.barta@ars.usda.gov
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.