Linked Life Data

10320339

Source:http://linkedlifedata.com/resource/pubmed/id/10320339

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1999-6-7
pubmed:abstractText
Three conserved glycine residues in the reactive thiol region of Dictyostelium discoideummyosin II were replaced by alanine residues. The resulting mutants G680A, G684A, and G691A were expressed in the soluble myosin head fragment M761-2R [Anson, M., Geeves, M. A., Kurzawa, S. E., and Manstein, D. J. (1996) EMBO J. 15, 6069-6074] and characterized using transient kinetic methods. Mutant G691A showed no major alterations except for a marked increase in basal Mg2+-ATPase activity. Phosphate release seemed to be facilitated by this mutation, and the addition of actin to G691A stimulated ATP turnover not more than 3-fold. In comparison to M761-2R, mutant constructs G691A and G684A showed a 4-fold reduction in the rate of the ATP cleavage step. Most other changes in the kinetic properties of G684A were small ( approximately 2-fold). In contrast, substitution of G680 by an alanine residue led to large changes in nucleotide binding. Compared to M761-2R, rates of nucleotide binding were 20-30-fold slower and the affinity for mantADP was approximately 10-fold increased due to a 200-fold reduction in the dissociation rate constant of mantADP. The ATP-induced dissociation of actin from the acto.680A complex was normal, but the communication between ADP and actin binding was altered such that the two sites are thermodynamically uncoupled but kinetically actin still accelerates ADP release.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6126-34
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Kinetic analysis of Dictyostelium discoideum myosin motor domains with glycine-to-alanine mutations in the reactive thiol region.
pubmed:affiliation
Max-Planck-Institut für Medizinische Forschung, Jahnstr. 29, D-69120 Heidelberg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't