Linked Life Data

3011539

Source:http://linkedlifedata.com/resource/pubmed/id/3011539

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1986-6-30
pubmed:abstractText
Regulation of various metabolic processes occurs by the phosphorylation/dephosphorylation of enzymes. Both the protein kinases that catalyze the phosphorylations and the protein phosphatases that catalyze the dephosphorylations display relatively broad specificity, reacting with a number of distinct sites in target enzymes. In this way changes in the activity of a particular kinase or phosphatase can cause coordinated and pleiotropic responses. However, the kinases and phosphatases do not exhibit a one-to-one correspondence in their reactions. Residues at different positions may be phosphorylated by a single kinase, yet dephosphorylated by different individual phosphatases. Conversely, sites which are substrates for different individual kinases may be dephosphorylated by a single phosphatase. In exploring the molecular basis for these differences this article shows that whereas kinases react with specific primary structures that often times appear as beta bends, the phosphatases recognize higher order structure, less strictly ruled by amino acid sequence surrounding the phosphorylated site. The differences, seen in the ability of these enzymes to utilize synthetic peptide substrates, might be rationalized in terms of function. Kinases need protruding segments of structure that can be enwrapped to exclude water, thereby minimizing ATP hydrolysis and enhancing phosphotransferase activity. On the other hand phosphatases are hydrolytic enzymes that may operate especially well on protein interfaces. Hydrolytic action often measured with p-nitrophenylphosphate is not necessarily indicative of a protein phosphatase and consideration of the mechanism reveals why this substrate can be misleading.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0020-711X
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
497-504
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Molecular basis for substrate specificity of protein kinases and phosphatases.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review