2QBV

Crystal Structure of Intracellular Chorismate Mutase from Mycobacterium Tuberculosis

Summary for 2QBV

• Entry DOI: 10.2210/pdb2qbv/pdb
• Descriptor: CHORISMATE MUTASE (2 entities in total)
• Functional Keywords: chorismate mutase, tuberculosis, intracellular, helical, dimeric, isomerase
• Biological source: Mycobacterium tuberculosis
• Total number of polymer chains: 1
• Total formula weight: 10107.81

Authors

Ladner, J.E.,Reddy, P.T.,Kim, S.K.,Reddy, S.-K.,Nelson, B.C. (deposition date: 2007-06-18, release date: 2007-06-26, Last modification date: 2023-08-30)

Primary citation

Kim, S.K.,Reddy, S.K.,Nelson, B.C.,Robinson, H.,Reddy, P.T.,Ladner, J.E.
A comparative biochemical and structural analysis of the intracellular chorismate mutase (Rv0948c) from Mycobacterium tuberculosis H(37)R(v) and the secreted chorismate mutase (y2828) from Yersinia pestis.
Febs J., 275:4824-4835, 2008

PubMed Abstract: The Rv0948c gene from Mycobacterium tuberculosis H(37)R(v) encodes a 90 amino acid protein as the natural gene product with chorismate mutase (CM) activity. The protein, 90-MtCM, exhibits Michaelis-Menten kinetics with a k(cat) of 5.5+/-0.2s(-1) and a K(m) of 1500+/-100microm at 37 degrees C and pH7.5. The 2.0A X-ray structure shows that 90-MtCM is an all alpha-helical homodimer (Protein Data Bank ID: 2QBV) with the topology of Escherichia coli CM (EcCM), and that both protomers contribute to each catalytic site. Superimposition onto the structure of EcCM and the sequence alignment shows that the C-terminus helix3 is shortened. The absence of two residues in the active site of 90-MtCM corresponding to Ser84 and Gln88 of EcCM appears to be one reason for the low k(cat). Hence, 90-MtCM belongs to a subfamily of alpha-helical AroQ CMs termed AroQ(delta.) The CM gene (y2828) from Yersinia pestis encodes a 186 amino acid protein with an N-terminal signal peptide that directs the protein to the periplasm. The mature protein, *YpCM, exhibits Michaelis-Menten kinetics with a k(cat) of 70+/-5s(-1) and K(m) of 500+/-50microm at 37 degrees C and pH7.5. The 2.1A X-ray structure shows that *YpCM is an all alpha-helical protein, and functions as a homodimer, and that each protomer has an independent catalytic unit (Protein Data Bank ID: 2GBB). *YpCM belongs to the AroQ(gamma) class of CMs, and is similar to the secreted CM (Rv1885c, *MtCM) from M.tuberculosis.

PubMed: 18727669
DOI: 10.1111/j.1742-4658.2008.06621.x

Experimental method

X-RAY DIFFRACTION (2 Å)