Dr. Jose Mendoza
Dr. Jose Mendoza
Professor of Chemistry

Office: SCI II 117
Phone: 760-750-4180
Dr. Mendoza is interested in deciphering how cells are protected by the "stress proteins".  These proteins protect cells from the adverse effects of stressful conditions (i.e. heat, oxidation, acid, etc.).  He is currently investigating the roles of the stress proteins in the survival of Helicobacter pylori in the stomach acidic environment.  About 50% of the human population is infected with this bacterium and chronic infection can, in certain individuals, give rise to gastric ulcers and gastric cancer.  This research involves a combination of biochemical and biophysical analyses of wild-type and mutant proteins.

Ph.D. Biochemistry, University of Texas Health Science Center at San Antonio, 1992

M.S. Organic Chemistry, University of Texas at El Paso, 1982

B.S. Chemistry, Instituto Tecnologico y de Estudios Superiores de Monterrey (Mexico), 1974

Mendoza, J.A., Correa, M.D., and Zardeneta, G. (2012) GTP binds to a-crystallin and causes a significant conformational change. Int. J. Biol. Macromol. 50, 895-898.
Melkani, G.C., Sielaff, R., Zardeneta, G., and Mendoza, J.A. (2012) Interaction of oxidized chaperonin GroEL with an unfolded protein at low temperatures. Biosci. Rep. 32, 299-303.
Melkani, G.C., Sielaff, R.L., Zardeneta, G., and Mendoza, J.A. (2008) Divalent cations stabilize GroEL under conditions of oxidative stress. Biochem. Biophys. Res. Commun. 368, 625-630.
Melkani, G.C., Kestetter, J., Sielaff, R., Zardeneta, G., and Mendoza, J.A. (2006) Protection of GroEL by its methionine residues against oxidation by hydrogen peroxide. Biochem. Biophys. Res. Commun. 347, 534-539.
Melkani, G.C., Zardeneta, G., and Mendoza, J.A. (2005) On the chaperonin activity of GroEL at heat-shock temperature. Int. J. Biochem. Cell Biol. 37, 1375-138.
Melkani, G.C., McNamara, C., Zardeneta, G., and Mendoza, J.A. (2004) Hydrogen peroxide induces the dissociation of GroEL into monomers that can facilitate the reactivation of oxidatively inactivated rhodanese. Int. J. Biochem. Cell Biol. 36, 505-518.
Melkani, G.C., Zardeneta, G., and Mendoza, J.A. (2004) Oxidized GroEL can function as a chaperonin. Frontiers Biosc. 9, 724-731.
Melkani, G.C., Zardeneta, G., and Mendoza, J.A. (2003) The ATPase activity of GroEL is supported at high temperatures by divalent cations that stabilize its structure. Biometals. 16, 479-484.
Melkani, G.C., Zardeneta, G., and Mendoza, J.A. (2002) GroEL interacts with oxidatively inactivated rhodanese facilitating its reactivation. Biochem. Biophys. Res. Commun. 294, 893-899.
Mendoza, J.A., Dulin, P., and Warren T. (2000) The Lower Hydrolysis of ATP by the Stress Protein GroEL Is a Major Factor Responsible for the Diminished Chaperonin Activity at Low Temperature. Cryobiology. 41, 319-323.
Del Fierro, D., Zardeneta, G., and Mendoza, J.A. (2000) a-Crystallin Facilitates the Reactivation of Hydrogen Peroxide-Inactivated Rhodanese. Biochem. Biophys. Res. Commun. 274, 461-466.
Mendoza, J.A., Warren T., and Dulin, P. (1996) The ATPase Activity of Chaperonin GroEL Is Highly Stimulated at Elevated Temperatures. Biochem. Biophys. Res. Commun. 229, 271-274.
Mendoza, J.A., and Del Campo, G. (1996) Ligand-induced Conformational Changes of GroEL Are Dependent on the Bound Substrate Polypeptide. J. Biol. Chem. 271, 16344-16349.
Mendoza, J.A., Wilson, M., Joves, F.,and Ackermann, E. (1996) Thermostabilization of Enzymes by the Chaperonin GroEL. Biotech.Techniques. 7, 535-540.
Mendoza, J.A., Martinez, J. L., and Horowitz, P.M. (1995) Tetradecameric-cpn60 Can Be Reassembled In Vitro from Monomers in a Process that Is ATP Independent and Influenced by Cpn10. Biochim. Biophys. Acta. 1247, 209-214.
Mendoza, J.A., and Horowitz, P.M. (1994) Bound Substrate Polypeptides Can Generally Stabilize the Tetradecameric Structure of Cpn60 and induce Its Reassembly from Monomers. J. Biol. Chem. 269, 25963-25965.
Mendoza, J.A., Demeler, B., and Horowitz, P.M. (1994) Alteration of the Quaternary Structure of Cpn60 Modulates Chaperonin Assisted Folding: Implications for the Mechanism of Chaperonin Action. J. Biol. Chem. 269, 2447-2451.
Mendoza, J.A., and Horowitz, P.M. (1994) The Chaperonin Assisted and Unassisted Refolding of Rhodanese Can Be Modulated by Its N-terminal Peptide. J. Protein Chem. 13, 15-22.
Goldenberg, D.P., Mendoza, J.A., and Zhang, J-X. (1994) Mutational Analysis of the BPTI Folding Pathway. Methods in Prot. Struct. Anal. 44, 483-492.
Mendoza, J.A., Jarsfter, M.B., and Goldenberg, D.P. (1994) Effects of Amino Acid Replacements on the Reductive Unfolding Kinetics of Pancreatic Trypsin Inhibitor. Biochemistry. 33, 1143-1148.
Mendoza, J.A., Grant,E., and Horowitz, P.M. (1993) Partially Folded Rhodanese or Its N-terminal Peptide Can Disrupt Phospholipid Vesicles. J. Protein Chem. 12, 65-69.
Mendoza, J.A., and Horowitz, P.M. (1992) Sulfhydryl Modification of E.coli Cpn60 Leads to Loss of Its Ability to Support Refolding of Rhodanese but not to Form a Binary Complex. J. Protein Chem. 11, 589-594.
Mendoza, J.A., Lorimer, G.H.,and Horowitz, P.M. (1992) Chaperonin Cpn60 from E.coli Protects the Mitochondrial Enzyme Rhodanese Against Heat Inactivation and Supports Folding at Elevated Temperatures. J. Biol. Chem. 267, 17631-17634.
Miller, D.M.,Kurzban, G.P., Mendoza, J.A., Chirgwin, J.M., Hardies, S.C., and Horowitz, P.M. (1992) Recombinant Bovine Rhodanese: Purification and Comparison with Bovine Liver Rhodanese. Biochim. Biophys. Acta. 1121, 286- 292.
Mendoza, J.A., Butler, M.C., and Horowitz, P.M. (1992) Characterization of a Stable, Reactivatable Complex Between Chaperonin 60 and Mitochondrial Rhodanese. J. Biol. Chem. 267, 24648-24654.
Mendoza, J.A., Lorimer, G.H., and Horowitz, P.M. (1991) Intermediates in the Chaperonin-Assisted Refolding of Rhodanese Are Trapped at Low Temperature and Show a Small Stoichiometry. J. Biol. Chem. 266, 16973- 16976.
Mendoza, J.A., Rogers, E., Lorimer, G.H., and Horowitz, P.M. (1991) Unassisted Refolding of Urea Unfolded Rhodanese. J. Biol. Chem. 266, 13587-13591.
Mendoza, J.A., Rogers, E., Lorimer, G.H., and Horowitz, P.M. (1991) Chaperonins Facilitate the in Vitro Folding of Monomeric Mitochondrial Rhodanese. J. Biol. Chem. 266, 13044-13049.