Bacillus anthracis spores are currently detected by established but slow microbiological test procedures. The development of faster, cheaper and higher-throughput detection methods would enable more effective responses to bio-terrorism and natural infectious disease outbreaks. Our goal is to engineer a reporter enzyme so that is inactive until it encounters a pathogen marker. Our design strategy is to imitate the twostep natural evolution of """"""""intrasteric"""""""" regulation. We have already generated a variant of the Escherichia coil beta-galactosidase (BGAL) that is specifically activated 5.7-fold when co-expressed with the human immuno-deficiency (HIV) protease. We believe that the E. coil alkaline phosphatase (AP) has even greater potential as a biosensor, and propose studies with the following specific aims: 1. to isolate effector-dependent AP variants with greater response to the HIV protease (>570% activation) and more robust enzyme activities. 2. to """"""""re-program"""""""" the best biosensor so that its activity becomes dependent upon the B. anthracis Lethal Factor (LF), the anti-influenza hemagglutinin (HA) antibody, or the anti-Yersinia pestis F1 antibody. 3. to array biosensors that respond to different effectors upon a chip for the rapid detection of pathogen markers. The biosensors generated in this study will streamline disease diagnosis by supplanting time-consuming and expensive immunoassays. These experiments will test the feasibility of our evolutionary hypothesis and demonstrate the utility of novel protein engineering techniques. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI054602-02
Application #
6721456
Study Section
Special Emphasis Panel (ZRG1-BECM (01))
Program Officer
Beanan, Maureen J
Project Start
2003-04-01
Project End
2006-03-31
Budget Start
2004-04-01
Budget End
2006-03-31
Support Year
2
Fiscal Year
2004
Total Cost
$266,000
Indirect Cost
Name
Emory University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
066469933
City
Atlanta
State
GA
Country
United States
Zip Code
30322
Greene, Dina N; Whitney, Spencer M; Matsumura, Ichiro (2007) Artificially evolved Synechococcus PCC6301 Rubisco variants exhibit improvements in folding and catalytic efficiency. Biochem J 404:517-24
Parikh, Monal R; Greene, Dina N; Woods, Kristen K et al. (2006) Directed evolution of RuBisCO hypermorphs through genetic selection in engineered E.coli. Protein Eng Des Sel 19:113-9
O'Loughlin, Taryn L; Greene, Dina N; Matsumura, Ichiro (2006) Diversification and specialization of HIV protease function during in vitro evolution. Mol Biol Evol 23:764-72
O'Loughlin, Taryn L; Matsumura, Ichiro (2006) HIV protease-activated molecular switches based on beta-glucuronidase and alkaline phosphatase. Comb Chem High Throughput Screen 9:313-20
Patrick, Wayne M; Firth, Andrew E (2005) Strategies and computational tools for improving randomized protein libraries. Biomol Eng 22:105-12
Parikh, Monal R; Matsumura, Ichiro (2005) Site-saturation mutagenesis is more efficient than DNA shuffling for the directed evolution of beta-fucosidase from beta-galactosidase. J Mol Biol 352:621-8