1B9D

MOBILITY OF AN HIV-1 INTEGRASE ACTIVE SITE LOOP IS CORRELATED WITH CATALYTIC ACTIVITY

1B9D の概要

• エントリーDOI: 10.2210/pdb1b9d/pdb
• 分子名称: PROTEIN (INTEGRASE), CACODYLATE ION, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: dna integration, transferase
• 由来する生物種: Human immunodeficiency virus
• 細胞内の位置: Gag-Pol polyprotein: Host cell membrane; Lipid-anchor . Matrix protein p17: Virion membrane; Lipid- anchor . Capsid protein p24: Virion . Nucleocapsid protein p7: Virion . Reverse transcriptase/ribonuclease H: Virion . Integrase: Virion : P12497
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 18282.52

構造登録者

Greenwald, J.,Le, V.,Butler, S.L.,Bushman, F.D.,Choe, S. (登録日: 1999-02-11, 公開日: 1999-07-19, 最終更新日: 2023-12-27)

主引用文献

Greenwald, J.,Le, V.,Butler, S.L.,Bushman, F.D.,Choe, S.
The mobility of an HIV-1 integrase active site loop is correlated with catalytic activity.
Biochemistry, 38:8892-8898, 1999

PubMed Abstract: Replication of HIV-1 requires the covalent integration of the viral cDNA into the host chromosomal DNA directed by the virus-encoded integrase protein. Here we explore the importance of a protein surface loop near the integrase active site using protein engineering and X-ray crystallography. We have redetermined the structure of the integrase catalytic domain (residues 50-212) using an independent phase set at 1.7 A resolution. The structure extends helix alpha4 on its N-terminal side (residues 149-154), thus defining the position of the three conserved active site residues. Evident in this and in previous structures is a conformationally flexible loop composed of residues 141-148. To probe the role of flexibility in this loop, we replaced Gly 140 and Gly 149, residues that appear to act as conformational hinges, with Ala residues. X-ray structures of the catalytic domain mutants G149A and G140A/G149A show further rigidity of alpha4 and the adjoining loop. Activity assays in vitro revealed that these mutants are impaired in catalysis. The DNA binding affinity, however, is minimally affected by these mutants as assayed by UV cross-linking. We propose that the conformational flexibility of this active site loop is important for a postbinding catalytic step.

PubMed: 10413462
DOI: 10.1021/bi9907173

実験手法

X-RAY DIFFRACTION (1.7 Å)