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Appointments

Member, Lombardi Cancer Center
Professor, Biochemistry and Molecular Biology

Education/Training

B.S. Biochemistry		1979		University of Califronia at Davis
Ph.D. Biological Chemistry		1988		University of California at Los Angeles
Postdoctoral Fellow Biochemistry		1992		Stanford University Medical Center

Research Interests

Initiation of chromosomal DNA replication is a key control point in the prokaryotic cell cycle and in the determination of eukaryotic cellular quiescence or proliferation. We are investigating the participation of the cell membrane in the regulation of DNA replication in E. coli. Mutagenesis and protein chemistry techniques are being employed to study the interaction between acidic phospholipids and the initiator protein, DnaA, and how their association participates in the cell-cycle control of chromosomal replication. A second project in the laboratory focuses on understanding the physiological role that cellular inorganic polyphosphates play in how cells respond to environmental stresses. These long, energy-rich polymers are found found in virtually all organisms. Disruption of the gene that encodes the polyphosphate biosynthetic enzyme, polyphosphate kinase (PPK), gives rise to cells that have decreased viability following exposure to environmental challenges such as heat, UV-irradiation and oxidative stress, or when the cells are maintained in the stationary phase for prolonged periods. Certain mutations elsewhere in the genome have the ability to suppress the sensitivities that ppk knock-out cells have toward these environmental stresses. Our identification of the genes that harbor such mutations will help us understand in which signal transduction and stress response pathways polyphosphates participate.

Recent Publications

View All PubMed articles by Crooke, E (May contain authors with the same name)

Camara J, Breier A, Brendler T, Austin S, Cozzarelli N and Crooke E (2005)
Hda inactivation of DnaA is the predominant mechanism preventing hyperinitiation of Escherichia coli DNA replication
EMBO Reports 6: 736-741.

Boeneman K and Crooke E (2005)
Chromosomal replication and the cell membrane
Curr Opin Microbiol 8: 143-148.

Li Z, Kitchen J, Boeneman K, Anand P and Crooke E (2005)
Restoration of growth to acidic phospholipid-deficient cells by DnaA(L366K) is independent of its capacity for nucleotide binding and exchange and requires DnaA
J Biol Chem 280: 9796-9801.

Ryan V, Grimwade J, Camara J, Crooke E and Leonard A (2004)
Escherichia coli prereplication complex assembly is regulated by dynamic interplay among Fis, IHF and DnaA
Mol Microbiol. 51: 1347-1359.

Camara J, Skarstad K and Crooke E (2003)
Controlled initiation of chromosomal replication in E. coli requires functional Hda protein
J. Bacteriol. 185: 3244-3248.

Kim P, Banack T, Lerman D, Tracy J, Camara J, Crooke E, Oliver D and Firshein W (2003)
Identification of a novel membrane-associated gene product that suppresses toxicity of a TrfA peptide from plasmid RK2 and its relationship to the DnaA host initiation protein.
J Bacteriol. 185: 1817-1824.

Zheng W, Li Z, Skarstad K and Crooke E (2001)
Mutations in DnaA protein suppress the growth-arrest of acidic phospholipid-deficient E. coli cells.
EMBO J. 20: 1164-1172.

Newman G and Crooke E (2000)
DnaA, the initiator of Escherichia coli chromosomal replication, is located at the cell membrane.
J. Bacteriol. 182: 2604-2610.

Kitchen J, Li Z and Crooke E (1999)
Electrostatic interactions during acidic phospholipid reactivation of DnaA protein, the E. coli initiator of chromosomal replication.
Biochemistry 38: 6213-6221.

Katayama T, Kubota T, Kurokawa K, Crooke E and Sekimizu K (1998)
The beta-subunit sliding clamp of DNA polymerase III, the E. coli replicase, renders DnaA protein inactive for initiating chromosomal replication
Cell 94: 61-71.

Last Modified: 12/27/2005 [/FMP-IF]