U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PUBLICATIONS

Biochemical and Structural Characterization of the Intracellular Chorismate Mutase (Rv0948c) From Mycobacterium Tuberculosis H37Rv

Published

Author(s)

Sung Kim, Sathyavelu K. Reddy, B C. Nelson, Prasad T. Reddy, Jane E. Ladner

Abstract

The Rv0948c gene from Mycobacterium tuberculosis H37Rv (Mt) encodes a 105 amino acid (aa) protein with chorismate mutase (CM) activity. Since the protein s amino terminus does not align with other CMs, we cloned a truncated version of the gene that yielded the protein beginning with Met16 (90 aa protein). Both proteins exhibit CM activity with identical kinetic parameters having a kcat of 7 s-1 and a Km of 1.5 0.1 mM at 37 oC and pH 7.5. Only the 90 aa protein, termed MtCM, produced crystals of diffraction quality to 2.0 resolution. MtCM exhibits two protomers in the molecule with all a-helical intertwined structure (PDB ID: 2QBV) having a topology similar to that of Escherichia coli CM (EcCM). However, superimposition of the structure of MtCM onto that of EcCM as well as the sequence alignment shows a shortened version of helix 3 in the carboxyl terminus of MtCM. The missing catalytic residues in helix 3 of MtCM corresponding to Ser84 and Gln88 of EcCM appear to be the reason for low kcat exhibited by MtCM. Hence, MtCM belongs to a new sub-family of a-helical class of AroQ CMs.
Citation
Journal of Biological Chemistry
Pub Type
Journals

Keywords

amino acid biosynthesis, AroQ protein, Chorismate mutase, Mycobacterium tuberculosis

Citation

Kim, S. , Reddy, S. , Nelson, B. , Reddy, P. and Ladner, J. (2021), Biochemical and Structural Characterization of the Intracellular Chorismate Mutase (Rv0948c) From Mycobacterium Tuberculosis H<sub>37</sub>R<sub>v</sub>, Journal of Biological Chemistry (Accessed April 19, 2024)

Created October 12, 2021