Abstract

The catalytic function of beta-lactamases is the primary mechanism of bacterial resistance to beta-lactam antibiotics. A multidisciplinary approach has been outlined for the study of beta-lactamases, which builds on the mechanistic findings from the principal investigator's laboratory in the current cycle of funding.
Four Specific Aims are outlined.
Specific Aim 1 details the plans for cloning, expression, large-scale production, crystallization and characterization of the mechanism of action of the oxo-10 beta-lactamase from Pseudomonas aeruginosa. This enzyme is a prototypic member of the class D of beta-lactamases, which are understood the least currently. This enzyme is the parent enzyme for a number of expanded-spectrum beta-lactamases, which have been identified clinically recently.
Specific Aim 2 describes the plans for investigation of the inhibitor-resistant TEM (""""""""IRT"""""""") beta-lactamases. A subset of beta-lactamases is being identified since 1992 that resist inhibition by clinically used inhibitors. Four of these enzymes carry individually single mutations of mechanistic consequence for the inhibitor-resistant trait. These enzymes will be investigated in mechanistic and crystallographic efforts to elucidate their catalytic properties.
Specific Aim 3 proposes a series of experiments in development of inhibitors for beta-lactamases that inhibit more than one class of these enzymes.
Specific Aim 4 details research in elucidating the mechanistic and structural aspects for turnover of imipenem, a clinically important beta-lactam antibiotic, by the common class A TEM-1 beta-lactamase. This system exhibits certain desirable characteristics that make it amenable to structural analysis at every step of the catalytic process for turnover. These efforts collectively will help define the dynamic system of random mutation in the resistance genes and the process of selection that have given considerable diversity to these resistance enzymes in clinical settings.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI033170-10
Application #
6510679
Study Section
Biochemistry Study Section (BIO)
Program Officer
Ikeda, Richard A
Project Start
1992-08-01
Project End
2005-06-30
Budget Start
2002-07-01
Budget End
2003-06-30
Support Year
10
Fiscal Year
2002
Total Cost
$331,373
Indirect Cost

  Institution

Name
Wayne State University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
City
Detroit
State
MI
Country
United States
Zip Code
48202

  Publications

Kumarasiri, Malika; Llarrull, Leticia I; Borbulevych, Oleg et al. (2012) An amino acid position at crossroads of evolution of protein function: antibiotic sensor domain of BlaR1 protein from Staphylococcus aureus versus clasS D ?-lactamases. J Biol Chem 287:8232-41
Borbulevych, Oleg; Kumarasiri, Malika; Wilson, Brian et al. (2011) Lysine Nzeta-decarboxylation switch and activation of the beta-lactam sensor domain of BlaR1 protein of methicillin-resistant Staphylococcus aureus. J Biol Chem 286:31466-72
Llarrull, Leticia I; Toth, Marta; Champion, Matthew M et al. (2011) Activation of BlaR1 protein of methicillin-resistant Staphylococcus aureus, its proteolytic processing, and recovery from induction of resistance. J Biol Chem 286:38148-58
Llarrull, Leticia I; Prorok, Mary; Mobashery, Shahriar (2010) Binding of the gene repressor BlaI to the bla operon in methicillin-resistant Staphylococcus aureus. Biochemistry 49:7975-7
Lemaire, Sandrine; Fuda, Cosimo; Van Bambeke, Francoise et al. (2008) Restoration of susceptibility of methicillin-resistant Staphylococcus aureus to beta-lactam antibiotics by acidic pH: role of penicillin-binding protein PBP 2a. J Biol Chem 283:12769-76
Totir, Monica A; Cha, Jooyoung; Ishiwata, Akihiro et al. (2008) Why clinically used tazobactam and sulbactam are poor inhibitors of OXA-10 beta-lactamase: Raman crystallographic evidence. Biochemistry 47:4094-101
Meroueh, Samy O; Bencze, Krisztina Z; Hesek, Dusan et al. (2006) Three-dimensional structure of the bacterial cell wall peptidoglycan. Proc Natl Acad Sci U S A 103:4404-9
Fisher, Jed F; Meroueh, Samy O; Mobashery, Shahriar (2005) Bacterial resistance to beta-lactam antibiotics: compelling opportunism, compelling opportunity. Chem Rev 105:395-424
Thomas, Veena L; Golemi-Kotra, Dasantila; Kim, Choonkeun et al. (2005) Structural consequences of the inhibitor-resistant Ser130Gly substitution in TEM beta-lactamase. Biochemistry 44:9330-8
Golemi-Kotra, Dasantila; Meroueh, Samy O; Kim, Choonkeun et al. (2004) The importance of a critical protonation state and the fate of the catalytic steps in class A beta-lactamases and penicillin-binding proteins. J Biol Chem 279:34665-73

Showing the most recent 10 out of 16 publications