2h9c
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Native Crystal Structure of the Isochorismate-Pyruvate Lyase from Pseudomonas aeruginosa
OverviewOverview
Enzymatic systems that exploit pericyclic reaction mechanisms are rare. A, recent addition to this class is the enzyme PchB, an 11.4-kDa, isochorismate pyruvate lyase from Pseudomonas aeruginosa. The apo and, pyruvate-bound structures of PchB reveal that the enzyme is a structural, homologue of chorismate mutases in the AroQalpha class despite low, sequence identity (20%). The enzyme is an intertwined dimer of three, helices with connecting loops, and amino acids from each monomer, participate in each of two active sites. The apo structure (2.35 A, resolution) has one dimer per asymmetric unit with nitrate bound in an, open active site. The loop between the first and second helices is, disordered, providing a gateway for substrate entry and product exit. The, pyruvate-bound structure (1.95 A resolution) has two dimers per asymmetric, unit. One has two open active sites like the apo structure, and the other, has two closed active sites with the loop between the first and second, helices ordered for catalysis. Determining the structure of PchB is part, of a larger effort to elucidate protein structures involved in siderophore, biosynthesis, as these enzymes are crucial for bacterial iron uptake and, virulence and have been identified as antimicrobial drug targets.
About this StructureAbout this Structure
2H9C is a Single protein structure of sequence from Pseudomonas aeruginosa with NO3 as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Two crystal structures of the isochorismate pyruvate lyase from Pseudomonas aeruginosa., Zaitseva J, Lu J, Olechoski KL, Lamb AL, J Biol Chem. 2006 Nov 3;281(44):33441-9. Epub 2006 Aug 16. PMID:16914555
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