1N8I

Biochemical and Structural Studies of Malate Synthase from Mycobacterium tuberculosis

Summary for 1N8I

• Entry DOI: 10.2210/pdb1n8i/pdb
• Related: 1n8w
• Descriptor: Probable malate synthase G, MAGNESIUM ION, GLYOXYLIC ACID, ... (4 entities in total)
• Functional Keywords: malate synthase, glyoxylate pathway, mycobacterium tuberculosis, acetyl coenzyme a, isocitrate lyase, persistence, glcb, structural genomics, psi, protein structure initiative, tb structural genomics consortium, tbsgc, lyase
• Biological source: Mycobacterium tuberculosis
• Cellular location: Cytoplasm (By similarity): P0A5J4
• Total number of polymer chains: 1
• Total formula weight: 80587.14

Authors

Smith, C.V.,Huang, C.C.,Miczak, A.,Russell, D.G.,Sacchettini, J.C.,Honer zu Bentrup, K.,TB Structural Genomics Consortium (TBSGC) (deposition date: 2002-11-20, release date: 2002-12-18, Last modification date: 2024-02-14)

Primary citation

Smith, C.V.,Huang, C.C.,Miczak, A.,Russell, D.G.,Sacchettini, J.C.,Honer Zu Bentrup, K.
Biochemical and structural studies of malate synthase from Mycobacterium tuberculosis
J.Biol.Chem., 278:1735-1743, 2003

PubMed Abstract: Establishment or maintenance of a persistent infection by Mycobacterium tuberculosis requires the glyoxylate pathway. This is a bypass of the tricarboxylic acid cycle in which isocitrate lyase and malate synthase (GlcB) catalyze the net incorporation of carbon during growth of microorganisms on acetate or fatty acids as the primary carbon source. The glcB gene from M. tuberculosis, which encodes malate synthase, was cloned, and GlcB was expressed in Escherichia coli. The influence of media conditions on expression in M. tuberculosis indicated that this enzyme is regulated differentially to isocitrate lyase. Purified GlcB had K(m) values of 57 and 30 microm for its substrates glyoxylate and acetyl coenzyme A, respectively, and was inhibited by bromopyruvate, oxalate, and phosphoenolpyruvate. The GlcB structure was solved to 2.1-A resolution in the presence of glyoxylate and magnesium. We also report the structure of GlcB in complex with the products of the reaction, coenzyme A and malate, solved to 2.7-A resolution. Coenzyme A binds in a bent conformation, and the details of its interactions are described, together with implications on the enzyme mechanism.

PubMed: 12393860
DOI: 10.1074/jbc.M209248200

Experimental method

X-RAY DIFFRACTION (2.1 Å)