Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7080
pubmed:dateCreated
2006-3-2
pubmed:databankReference
pubmed:abstractText
Interferons are immunomodulatory cytokines that mediate anti-pathogenic and anti-proliferative effects in cells. Interferon-gamma-inducible human guanylate binding protein 1 (hGBP1) belongs to the family of dynamin-related large GTP-binding proteins, which share biochemical properties not found in other families of GTP-binding proteins such as nucleotide-dependent oligomerization and fast cooperative GTPase activity. hGBP1 has an additional property by which it hydrolyses GTP to GMP in two consecutive cleavage reactions. Here we show that the isolated amino-terminal G domain of hGBP1 retains the main enzymatic properties of the full-length protein and can cleave GDP directly. Crystal structures of the N-terminal G domain trapped at successive steps along the reaction pathway and biochemical data reveal the molecular basis for nucleotide-dependent homodimerization and cleavage of GTP. Similar to effector binding in other GTP-binding proteins, homodimerization is regulated by structural changes in the switch regions. Homodimerization generates a conformation in which an arginine finger and a serine are oriented for efficient catalysis. Positioning of the substrate for the second hydrolysis step is achieved by a change in nucleotide conformation at the ribose that keeps the guanine base interactions intact and positions the beta-phosphates in the gamma-phosphate-binding site.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
2
pubmed:volume
440
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
101-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16511497-5'-Guanylic Acid, pubmed-meshheading:16511497-Arginine, pubmed-meshheading:16511497-Binding Sites, pubmed-meshheading:16511497-Catalysis, pubmed-meshheading:16511497-Crystallography, X-Ray, pubmed-meshheading:16511497-Dimerization, pubmed-meshheading:16511497-GTP Phosphohydrolases, pubmed-meshheading:16511497-GTP-Binding Proteins, pubmed-meshheading:16511497-Guanosine Diphosphate, pubmed-meshheading:16511497-Guanosine Triphosphate, pubmed-meshheading:16511497-Humans, pubmed-meshheading:16511497-Hydrolysis, pubmed-meshheading:16511497-Models, Molecular, pubmed-meshheading:16511497-Phosphates, pubmed-meshheading:16511497-Protein Binding, pubmed-meshheading:16511497-Protein Structure, Quaternary, pubmed-meshheading:16511497-Protein Structure, Tertiary, pubmed-meshheading:16511497-Serine, pubmed-meshheading:16511497-Structure-Activity Relationship
pubmed:year
2006
pubmed:articleTitle
How guanylate-binding proteins achieve assembly-stimulated processive cleavage of GTP to GMP.
pubmed:affiliation
Abteilung Strukturelle Biologie, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't