1M9X

X-ray crystal structure of Cyclophilin A/HIV-1 CA N-terminal domain (1-146) M-type H87A,A88M,G89A Complex.

Summary for 1M9X

• Entry DOI: 10.2210/pdb1m9x/pdb
• Related: 1AK4 1M96 1M9C 1M9D 1M9E 1M9F 1m9y
• Descriptor: Cyclophilin A, HIV-1 Capsid (3 entities in total)
• Functional Keywords: capsid, hiv-1, cyclophilin a, rotamase, isomerase-viral protein complex, isomerase/viral protein
• Biological source: Homo sapiens (human); More
• Cellular location: Cytoplasm: P62937; Matrix protein p17: Virion (By similarity): Q72497
• Total number of polymer chains: 8
• Total formula weight: 136992.60

Authors

Howard, B.R.,Vajdos, F.F.,Li, S.,Sundquist, W.I.,Hill, C.P. (deposition date: 2002-07-30, release date: 2003-05-27, Last modification date: 2024-02-14)

Primary citation

Howard, B.R.,Vajdos, F.F.,Li, S.,Sundquist, W.I.,Hill, C.P.
Structural insights into the catalytic mechanism of cyclophilin A
Nat.Struct.Biol., 10:475-481, 2003

PubMed Abstract: Cyclophilins constitute a ubiquitous protein family whose functions include protein folding, transport and signaling. They possess both sequence-specific binding and proline cis-trans isomerase activities, as exemplified by the interaction between cyclophilin A (CypA) and the HIV-1 CA protein. Here, we report crystal structures of CypA in complex with HIV-1 CA protein variants that bind preferentially with the substrate proline residue in either the cis or the trans conformation. Cis- and trans-Pro substrates are accommodated within the enzyme active site by rearrangement of their N-terminal residues and with minimal distortions in the path of the main chain. CypA Arg55 guanidinium group probably facilitates catalysis by anchoring the substrate proline oxygen and stabilizing sp3 hybridization of the proline nitrogen in the transition state.

PubMed: 12730686
DOI: 10.1038/nsb927

Experimental method

X-RAY DIFFRACTION (1.7 Å)