Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
1996-1-25
pubmed:abstractText
The myosin head consists of a globular motor or catalytic domain that contains both the catalytic and actin binding sites, and a neck region which consists of a 8.5 nm alpha-helix that emerges from the globular part of the heavy chain and is stabilized by the binding of the essential and regulatory light chains. High levels of M754, a recombinant polyhistidine-tagged catalytic domain-like fragment of myosin II, were produced in Dictyostelium discoideum and purified using a rapid extraction protocol and metal chelate chromatography. Approximately 1.2 mg of homogeneous, functional protein was obtained per gram of cells. Kinetic analysis of M754 showed that the recombinant protein still has all the typical properties of a myosin ATPase. However, the removal of the light chain domain does have a pronounced effect on enzymatic activity. Nucleotide on-rates are 7-16-fold slower for M754 than for a myosin head fragment that includes the neck region. In contrast, the rate of ATP binding and dissociating the actin-bound catalytic domain is 10-fold increased. Overall the results indicate that the truncation of the heavy chain affects the nucleotide binding site and the communication between the nucleotide and actin binding sites. Furthermore, it seems that the nucleotide site of M754 is not fully formed but binding to actin or ATP stabilizes the structure in general and the nucleotide binding site in particular.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16056-64
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:8519762-Adenosine Diphosphate, pubmed-meshheading:8519762-Adenosine Triphosphate, pubmed-meshheading:8519762-Animals, pubmed-meshheading:8519762-Base Sequence, pubmed-meshheading:8519762-Binding, Competitive, pubmed-meshheading:8519762-Binding Sites, pubmed-meshheading:8519762-Catalysis, pubmed-meshheading:8519762-Cloning, Molecular, pubmed-meshheading:8519762-DNA Primers, pubmed-meshheading:8519762-Dictyostelium, pubmed-meshheading:8519762-Histidine, pubmed-meshheading:8519762-Kinetics, pubmed-meshheading:8519762-Molecular Sequence Data, pubmed-meshheading:8519762-Mutagenesis, Site-Directed, pubmed-meshheading:8519762-Myosins, pubmed-meshheading:8519762-Open Reading Frames, pubmed-meshheading:8519762-Polymerase Chain Reaction, pubmed-meshheading:8519762-Recombinant Proteins, pubmed-meshheading:8519762-Restriction Mapping, pubmed-meshheading:8519762-Sequence Tagged Sites
pubmed:year
1995
pubmed:articleTitle
Kinetic characterization of the catalytic domain of Dictyostelium discoideum myosin.
pubmed:affiliation
National Institute for Medical Research, London, U.K.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't