Proton-translocating ATPases catalyze oxidative phosphorylation in mitochondria, chloroplasts and bacteria. This work will examine the factors involved in the biogenesis (synthesis and assembly) of the proton-translocating ATPase of E. coli. Although the genes for the 8 subunits of this ATPase are arranged in equal numbers in an operon (the unc operon), the expression of those genes reflects the fact that the subunits are present in different numbers in the ATPase complex. The proposed research will investigate how the expression of several of these genes is controlled and how changes in that control affect the ATPase and E. coli carrying those mutations. Expression of ATPase genes will be studied two ways. The protein products of an in vitro transcription-translation system directed by ATPase genes cloned onto different plasmids will be quantitated, and Beta-galactosidase activity will be measured from gene fusions between ATPase genes and lac Z. Mutations in regions controlling expression of unc genes will be constructed in vitro using recombinant DNA techniques or will be isolated in vivo by screening for increased expression of Beta-galactosidase from unc-lac gene fusions. The phenotypes of cells carrying such mutations will be studied in an effort to relate deregulation of subunit expression to the structure of function of the ATPase. The role of mRNA secondary structure in controlling expression of different genes will be studied in vitro using synthetic oligonucleotides to disrupt such structures. Also, the initial events in the assembly of the F1 ATPase will be investigated in the in vitro system by using antibodies raised against individual subunits to precipitate complexes formed between the antigen-subunit and other F1 subunits. For these studies, the in vitro transcription-translation system can be manipulated at 3 levels: 1) which genes are to be expressd, 2) which subunit will be precipitated, and 3) which purified subunits can be added to the reactions to affect the formation of complexes.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI020010-02
Application #
3129480
Study Section
Microbial Physiology and Genetics Subcommittee 2 (MBC)
Project Start
1984-12-01
Project End
1987-11-30
Budget Start
1985-12-01
Budget End
1986-11-30
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost
Name
University of Maryland College Park
Department
Type
Earth Sciences/Resources
DUNS #
City
College Park
State
MD
Country
United States
Zip Code
20742
Solomon, K A; Hsu, D K; Brusilow, W S (1989) Use of lacZ fusions to measure in vivo expression of the first three genes of the Escherichia coli unc operon. J Bacteriol 171:3039-45
Pati, S; Brusilow, W S (1989) The roles of the alpha and gamma subunits in proton conduction through the Fo sector of the proton-translocating ATPase of Escherichia coli. J Biol Chem 264:2640-4
Angov, E; Brusilow, W S (1988) Use of lac fusions to measure in vivo regulation of expression of Escherichia coli proton-translocating ATPase (unc) genes. J Bacteriol 170:459-62
Solomon, K A; Brusilow, W S (1988) Effect of an uncE ribosome-binding site mutation on the synthesis and assembly of the Escherichia coli proton-translocating ATPase. J Biol Chem 263:5402-7
Hawthorne, C A; Brusilow, W S (1988) Sequence of the genes for the beta and epsilon subunits of the ATP synthase of Bacillus megaterium QM B1551. Biochem Biophys Res Commun 151:926-31
Martin, S A; Rosenthal, R S; Biemann, K (1987) Fast atom bombardment mass spectrometry and tandem mass spectrometry of biologically active peptidoglycan monomers from Neisseria gonorrhoeae. J Biol Chem 262:7514-22
Brusilow, W S (1987) Proton leakiness caused by cloned genes for the F0 sector of the proton-translocating ATPase of Escherichia coli: requirement for F1 genes. J Bacteriol 169:4984-90
Hawthorne, C A; Brusilow, W S (1986) Complementation of mutants in the Escherichia coli proton-translocating ATPase by cloned DNA from Bacillus megaterium. J Biol Chem 261:5245-8