The P-loop--a common motif in ATP- and GTP-binding proteins

Trends Biochem Sci. 1990 Nov;15(11):430-4. doi: 10.1016/0968-0004(90)90281-f.


Many ATP- and GTP-binding proteins have a phosphate-binding loop (P-loop), the primary structure of which typically consists of a glycine-rich sequence followed by a conserved lysine and a serine or threonine. The three-dimensional structures of several ATP- and GTP-binding proteins containing P-loops have now been solved. In this review current knowledge of P-loops is discussed with the additional aim of illustrating the fascinating relationship between protein sequence, structure and function.

Publication types

  • Review

MeSH terms

  • Adenosine Triphosphate / metabolism*
  • Amino Acid Sequence
  • Animals
  • GTP-Binding Proteins / chemistry*
  • GTP-Binding Proteins / genetics
  • Humans
  • Molecular Sequence Data
  • Mutation
  • Protein Conformation
  • Proteins / chemistry*
  • Proteins / genetics
  • Proteins / metabolism
  • Sequence Homology, Nucleic Acid


  • Proteins
  • Adenosine Triphosphate
  • GTP-Binding Proteins