Anne Delcour, Ph.D.
Professor, Biology and Biochemistry
University of Houston
B.S. Zoology, University of Liege (1981)
Ph.D. Biochemistry, Cornell University (1986)
Dr. Delcour is interested in the molecular mechanisms of ion channel function and modulation. In particular, her lab is focused on the study of bacterial pore-forming proteins because bacteria are a convenient system where electrophysiological, biochemical and genetic studies can be performed. They use the patch clamp and planar bilayer techniques to measure the electrical activity of single channel proteins in real time. The computer analysis of the data gives information on the size and selectivity of the ion channel, kinetic properties, dependence on transmembrane voltage or on other physical or chmical parameters, and mechanisms of modulation.
A current major thrust of her laboratory is the study of the pore-forming proteins of various secretion systems. Bacteria secrete a vast array of protein, such as toxins, enzymes, adhesins, and cell surface appendages , many of which play important roles in the virulence of pathogenic species. Secretion machineries in variable include membrane-bound pore-forming proteins that provide a pathway for the export of the secreted polypeptide substrates or the injection of toxins inside eukaryotic host cells. These pores represent potential new targets of anti-infective agents, as the transported substrates are often key elembents in the infection process. The molecular mechanisms by which the pores recognize and transport their cognate substrates are poorly understood. Dr. Delcour's laboratory is using the unique approach of applying electrophysiology to investigate the properties of some of these protein-transporting channels in a variety of micro-organisms. In particular, she has ongoing collaborations with Dr. David Thanassi (Stony Brook) on the PapC usher of uropathogenic E. coli, Dr. Hye-Jeong Yeo (UH) on the TpsB of the two partner secretion system of H. Influenzae, and Dr. Ina Attrée (Grenoble, France) on the translocon of the Type III secretion system of Pseudomonas aeruginosa. All these pore-forming proteins are characterized by distinct electrophysiological signatures and properties. The interests of the laboratory are to uncover the molecular mechanisms for the function (and in some cases assembly) of these pores through structure-function relationship approaches, and to use electrophysiology as an assay to monitor the process of transport of the protein substrates.
Another interest of her lab is the porins, abundant channels of the outer membrane of Gram-negative bacteria. In particular, her lab has made important contributions to the molecular understanding of the function and modulation of the porins from Escherichia coli (a member of the gut microbiota) and Vibro cholerae (the agent of cholera). These proteins play an essential role in the survival of the cell, and their study is of great interest not only in the broad scope of fundamental research on ion channels and bacteria physiology, but also with respect to potential medical applications. The lab studies the relationships between structure and function by performing electrophysiological experiments on genetically engineered mutant channels. The responses of the porins to acidic pH and bile acids, in particular, are investigated, as these parameters represent physiologically relevant modulators for these enteric organisms.
- Wager B, Faudry E, Wills T, Attree I and Delcour AH. Current fluctuation analysis of the PopB and PopD translocon components of the Psedomonas aeruginosa type III secretion system. Biophys J, 104(7):1445-55 (2013). PubMed
- Mapingire OS, Wager B and Delcour AH. Electrophysiological characterization of bacterial pore-forming proteins in planar lipid bilayers. Methods Mol Biol, 966:381-96 (2013). PubMed
- Pagel M and Delcour AH. Effects of conjugated and unconjgated bile acids on the activity of the Vibrio cholerae porin OmpT. Molec Membr Biology, 28:69-78 (2011). PubMed
- Wager B, Baslé A and Delcour AH. Disulfide bond tethering of extracellular loops does not affect the closure of OmpF porin at acidic pH. Proteins, 78: 2886-2894 (2010). PubMed
- Duret G and Delcour AH. Size and dynamics of the Vibrio cholerae porins OmpU and OmpT probed by polymer exclusion. Biophys J., 98:1820-1829 (2010). PubMed
- Mapingire OS, Henderson NS, Duret G, Thanassi DG and Delcour AH. Modulating Effects of the Plug, Helix and N- and C-terminal Domains on Channel Properties of the PapC Usher. J Biol Chem, 284: 36324-36333 (2009). PubMed
- Duret G, Szmanski M, Choi K-J, Yeo H-J, and Delcour AH. The TpsB Translocator HMW1B of Hemophilus influenzae Forms a Large-Conductance Channel. J Biol Chem, 283: 15771-15778 (2008). PubMed
For more publications, see listing on PubMed
Department: Biology & Biochemistry
Address: 369 Science & Research Bldg II
University of Houston
Houston, Texas 77204-5001
Web: University of Houston