1Q9J

Structure of polyketide synthase associated protein 5 from Mycobacterium tuberculosis

Summary for 1Q9J

• Entry DOI: 10.2210/pdb1q9j/pdb
• Descriptor: Polyketide synthase associated protein 5 (2 entities in total)
• Functional Keywords: polyketide synthase associated protein; conjugating enzyme papa5; mycobacterium tuberculosis, structural genomics, psi, protein structure initiative, new york sgx research center for structural genomics, nysgxrc, ligase
• Biological source: Mycobacterium tuberculosis
• Total number of polymer chains: 2
• Total formula weight: 90931.06

Authors

Buglino, J.,Onwueme, K.C.,Quadri, L.E.,Lima, C.D.,Burley, S.K.,New York SGX Research Center for Structural Genomics (NYSGXRC) (deposition date: 2003-08-25, release date: 2004-05-25, Last modification date: 2024-02-14)

Primary citation

Buglino, J.,Onwueme, K.C.,Ferreras, J.A.,Quadri, L.E.,Lima, C.D.
Crystal Structure of PapA5, a Phthiocerol Dimycocerosyl Transferase from Mycobacterium tuberculosis
J.Biol.Chem., 279:30634-30642, 2004

PubMed Abstract: Polyketide-associated protein A5 (PapA5) is an acyltransferase that is involved in production of phthiocerol and phthiodiolone dimycocerosate esters, a class of virulence-enhancing lipids produced by Mycobacterium tuberculosis. Structural analysis of PapA5 at 2.75-A resolution reveals a two-domain structure that shares unexpected similarity to structures of chloramphenicol acetyltransferase, dihydrolipoyl transacetylase, carnitine acetyltransferase, and VibH, a non-ribosomal peptide synthesis condensation enzyme. The PapA5 active site includes conserved histidine and aspartic acid residues that are critical to PapA5 acyltransferase activity. PapA5 catalyzes acyl transfer reactions on model substrates that contain long aliphatic carbon chains, and two hydrophobic channels were observed linking the PapA5 surface to the active site with properties consistent with these biochemical activities and substrate preferences. An additional alpha helix not observed in other acyltransferase structures blocks the putative entrance into the PapA5 active site, indicating that conformational changes may be associated with PapA5 activity. PapA5 represents the first structure solved for a protein involved in polyketide synthesis in Mycobacteria.

PubMed: 15123643
DOI: 10.1074/jbc.M404011200

Experimental method

X-RAY DIFFRACTION (2.75 Å)