Skip to content Skip to navigation
University of Warwick
  • Study
  • |
  • Research
  • |
  • Business
  • |
  • Alumni
  • |
  • News
  • |
  • About

University of Warwick
Publications service & WRAP

Highlight your research

  • WRAP
    • Home
    • Search WRAP
    • Browse by Warwick Author
    • Browse WRAP by Year
    • Browse WRAP by Subject
    • Browse WRAP by Department
    • Browse WRAP by Funder
    • Browse Theses by Department
  • Publications Service
    • Home
    • Search Publications Service
    • Browse by Warwick Author
    • Browse Publications service by Year
    • Browse Publications service by Subject
    • Browse Publications service by Department
    • Browse Publications service by Funder
  • Help & Advice
University of Warwick

The Library

  • Login
  • Admin

Characterization of Mycobacterium tuberculosis diaminopimelic acid epimerase: paired cysteine residues are crucial for racemization

Tools
- Tools
+ Tools

Usha, Veeraraghavan, Dover, Lynn G., Roper, David I. and Besra, Gurdyal S. (2008) Characterization of Mycobacterium tuberculosis diaminopimelic acid epimerase: paired cysteine residues are crucial for racemization. FEMS Microbiology Letters, Vol.280 (No.1). pp. 57-63. doi:10.1111/j.1574-6968.2007.01049.x ISSN 0378-1097.

Research output not available from this repository.

Request-a-Copy directly from author or use local Library Get it For Me service.

Official URL: http://dx.doi.org/10.1111/j.1574-6968.2007.01049.x

Request Changes to record.

Abstract

Recently, the overproduction of Mycobacterium tuberculosis diaminopimelic acid (DAP) epimerase MtDapF in Escherichia coli using a novel codon alteration cloning strategy and the characterization of the purified enzyme was reported. In the present study, the effect of sulphydryl alkylating agents on the in vitro activity of M. tuberculosis DapF was tested. The complete inhibition of the enzyme by 2-nitro-5-thiocyanatobenzoate, 5,5'-dithio-bis(2-nitrobenzoic acid) and 1,2-benzisothiazolidine-3-one at nanomolar concentrations suggested that these sulphydryl alkylating agents modify functionally significant cysteine residues at or near the active site of the epimerase. Consequently, the authors extended the characterization of MtDapF by studying the role of the two strictly conserved cysteine residues. The putative catalytic residues Cys87 and Cys226 of MtDapF were replaced individually with both serine and alanine. Residual epimerase activity was detected for both the serine replacement mutants C87S and C226S in vitro. Kinetic analyses revealed that, despite a decrease in the K-M value of the C87S mutant for DAP that presumably indicates an increase in nonproductive substrate binding, the catalytic efficiency of both serine substitution mutants was severely compromised. When either C87 or C226 were substituted with alanine, epimerase activity was not detected emphasizing the importance of both of these cysteine residues in catalysis.

Item Type: Journal Article
Subjects: Q Science > QP Physiology
Q Science > QR Microbiology
Divisions: Faculty of Science, Engineering and Medicine > Science > Life Sciences (2010- )
Library of Congress Subject Headings (LCSH): Mycobacterium tuberculosis, Peptidoglycans, Isomerases, Cysteine proteinases, Racemization
Journal or Publication Title: FEMS Microbiology Letters
Publisher: Wiley-Blackwell Publishing Ltd.
ISSN: 0378-1097
Official Date: March 2008
Dates:
DateEvent
March 2008Published
Volume: Vol.280
Number: No.1
Number of Pages: 7
Page Range: pp. 57-63
DOI: 10.1111/j.1574-6968.2007.01049.x
Status: Peer Reviewed
Publication Status: Published
Access rights to Published version: Restricted or Subscription Access
Funder: The Darwin Trust of Edinburgh, Royal Society (Great Britain), Wellcome Trust (London, England), Medical Research Council (Great Britain) (MRC)

Data sourced from Thomson Reuters' Web of Knowledge

Request changes or add full text files to a record

Repository staff actions (login required)

View Item View Item
twitter

Email us: wrap@warwick.ac.uk
Contact Details
About Us