Skip Navigation



Journal of Biochemistry Advance Access published online on December 15, 2007
Journal of Biochemistry, doi:10.1093/jb/mvm237
This Article
Right arrow Advance Access manuscript (PDF)
Right arrow All Versions of this Article:
143/3/417    most recent
mvm237v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Kurokawa, K.
Right arrow Articles by Sekimizu, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kurokawa, K.
Right arrow Articles by Sekimizu, K.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2007 The Japanese Biochemical Society

Staphylococcus aureus MurC participates in L-Alanine Recognition via Histidine 343, a Conserved Motif in the Shallow Hydrophobic Pocket

Kenji Kurokawa1,2,*, Satoshi Nishida1,2,3, Mihoko Ishibashi1, Hikaru Mizumura1, Kohji Ueno3, Takashi Yutsudo4, Hideki Maki4, Kazuhisa Murakami4 and Kazuhisa Sekimizu1

1Laboratory of Microbiology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; 3Laboratory of Microbiology, Research Institute of Pharmaceutical Sciences, Musashino University, Tokyo 202-8585, Japan; and 4Discovery Research Laboratories, Shionogi & Co., Ltd., Osaka 561-0825, Japan

*To whom correspondence should be addressed. Laboratory of Microbiology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. Tel: +81-3-5841-4821, Fax: +81-3-5684-2973, E-mail: kurokawa{at}mol.f.u-tokyo.ac.jp

Received October 26, 2007; Accepted November 26, 2007


  Abstract

UDP-N-acetylmuramic acid:L-alanine ligase, which is encoded by the murC gene, is indispensable for bacterial peptidoglycan biosynthesis and an important target for the development of antibacterial agents. Structure of MurC ligase with substrates has been described, however, little validation via studying the effects of mutations on the structure of MurC has been performed. In this study, we carried out a functional in vitro and in vivo characterization of Staphylococcus aureus MurCH343Y protein, which has a temperature-sensitive mutation of a conserved residue in the predicted shallow hydrophobic pocket that holds a short L-alanine side chain. Purified H343Y and wild-type MurC had Km values for L-alanine of 3.2 mM and 0.44 mM, respectively, whereas there was no significant difference in their Km values for ATP and UDP-N-acetylmuramic acid, suggesting the specific alteration of L-alanine recognition in MurCH343Y protein. In a synthetic medium that excluded L-alanine, S. aureus murCH343Y mutant cells showed an allele-specific slow growth phenotype that was suppressed by addition of L-alanine. These results suggest that His343 of S. aureus MurC is essential for high-affinity binding to L-alanine both in vitro and in vivo and provide experimental evidence supporting the structural information of MurC ligase.

Key Words: Gram-positive bacteria, MurC, Peptidoglycan, Staphylococcus aureus, UDP-N-acetylmuramic acid:L-alanine ligase

2The first two authors equally contributed to this work.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.