Michael Blaber, Ph.D. Professor of Biomedical Sciences College of Medicine Florida State University College of Medicine Dept. of Biomedical Sciences 1115 West Call Street Tallahassee, FL 32306-4300 Dr. Blaber's Faculty Profile
Research Interests
Proteins are the "workhorse" molecules of living systems, providing both the structural elements of cells and tissues, as well as molecular machinery that permits the myriad and complex functions of living systems. The production of large quantities of human proteins by genetic engineering technology has opened up a new field of human therapeutics known as "biopharmaceuticals", and proteins are now the fastest-growing category of new drug approvals by the FDA. Some examples of biopharmaceuticals include erythropoietin (to treat anemia), tissue plasminogen activator (to treat myocardial infarction), and herceptin (to treat metastatic breast cancer). These are just a few examples; the FDA has currently approved over 300 biopharmaceuticals. The economic impact of such proteins is in the hundreds of billions of dollars; and the impact upon human health and quality of life has been immeasureable. Basic scientific studies of protein structure and biophysical properties allow us to form hypotheses regarding the molecular basis of protein function. In turn, this knowledge allows us to propose ways in which proteins might be modified (i.e. "engineered") to enhance their properties. Such "second generation" forms of proteins may permit more efficient application as biopharmaceuticals. Thus, one of the main goals of our research program is to both expand fundamental understanding of proteins and to apply this knowledge in the development of proteins for human benefit.
Current Research Projects
HUMAN FIBROBLAST GROWTH FACTOR-1 (FGF-1) FGF-1 is a fascinating protein from a number of standpoints. It is a member of the "beta trefoil" superfold, which means it exhibits three-fold symmetry in its overall architecture. A number of investigators have suggested that this is evidence that it evolved from a series of gene duplication/fusion events. However, a curious aspect of this structural symmetry is that while it is pronounced at the level of the protein backbone, it is essentially absent when looking at the amino acid sequence. The reasons for this disconnect between the primary and tertiary structure symmetry are unclear, but may have important implications for protein evolution and design. Functionally, FGF-1 is a potent mitogen of vascular endothelial cells, and is therefore a "pro-angiogenic" factor (causing blood vessels to grow at the site of FGF-1 administration. This property has been studied by investigators interested in getting the body to grow new blood vessels into tissues that are starved for oxygen (as in the heart due to coronary occlusion). Human clinical trials have had some amazing results in this area and suggest that FGF-1 can be used as a new type of biopharmaceutical to treat such patients. However, FGF-1 has biophysical properties of stability and folding that complicate its use as a typical drug. We are studying the fundamental properties of folding and stability of FGF-1; these studies are contributing to a better understanding of general protein folding. Subsequently, this information is being used to develop novel forms of FGF-1 with enhanced properties for human "pro-angiogenic" therapy. HUMAN KALLIKREIN-RELATED PEPTIDASES (KLKs) The KLKs are a family of serine-type proteases. For years it was believed there were only 3 such members (KLK1-3); however, work over the past decade has shown there are a total of 15 members in the human proteome - making the KLKs the largest family of serine-type proteases in the human. Little is known regarding the function of the KLKs, although recent work shows they are involved in the normal development of skin and teeth, and also play a role in fertilization as well as inflammation. One of the most important current applications of the KLKs is their use as biomarkers for disease; in particular, KLK3 is also known as "prostate specific antigen" (PSA), and elevated levels are correlated with prostate cancer. Regulation of the function of KLKs is a keen area of interest, particularly as it relates to activation of the KLKs. The KLKs are initially secreted as inactive pro-forms, which must be proteolytically processed to yield the mature active form. Since the KLKs are proteases, there has been much speculation regarding the ability of the KLK family to participate in "activation cascades" (much like the thrombostasis system of proteases). Once such cascades are identified, key data of interest relates to the specific catalytic constants of activation (i.e. Michaelis constants)- as this knowledge will permit computational modeling of such cascades. We are studying the KLK activation cascades, and in particular, the involvment of KLK6. We have data to indicate that KLK6 is involved in inflammatory demyelination, such as occurs in Multiple Sclerosis, and controlling its activity may represent a new therapy in the treatment of such disease.
Students in the laboratory can gain the following skill set:
Protein Chemistry Expression of recombinant proteins (prokaryotic and eukaryotic hosts) Purification of recombinant proteins (including liquid chromatography) Enzymology Biophysics Stopped-flow kinetics Isothermal equilibrium denaturation Differential scanning calorimetry (DSC) Isothermal titration calorimetry (ITC) Surface plasmon resonance (SPR) Circular dichroism (CD) Structural biology X-ray crystal structure determination Molecular modeling
Selected References
Structural Basis for the Conserved Cysteine in the Fibroblast Growth Factor Family: Evidence for a Vestigial Half-Cystine, Lee, J. and Blaber, M. (submitted)   The Interaction between Thermostability and Buried Free Cysteines in Regulating the Functional Half-Life of Fibroblast Growth Factor-1, Lee, J. and Blaber, M. (submitted)   A Completed KLK Activome Profile: Investigation of Activation Profiles of KLK9, 10 and 15, Yoon, H., Blaber, S.I., Debela, M., Goettig, P., Scarisbrick, I.A. and Blaber, M., Biological Chemistry 390, 373-377 (2009)   S1’ and S2’ Subsite Specificities of Human Plasma Kalikrein and Tissue Kallikrein 1 on the Hydrolysis of Peptides Derived from Bradykinin Domain of Human Kininogen, Lima, A.R., Alves, F.M., Angelo, P.F., Andrade, D., Blaber, S.I., Blaber, M., Juliano. L. and Juliano, M.A., Biological Chemistry 389, 1487-1494 (2008)   Protease Activated Receptor Dependent and Independent Signaling by Kallikreins 1 and 6 in CNS Neuron and Astroglial Cell Lines, Vandell, A.G., Larson, N., Laxmikanthan, G., Panos, M., Blaber, S.I., Blaber, M. and Scarisbrick, I.A., J. Neurochem. 107, 855-870 (2008)   Activation Profiles of Human Kallikrein-related Peptidases by Proteases of the Thrombostasis Axis, Yoon, H., Blaber, S.I., Evans, D.M., Trim, J., Juliano, M.A., Scarisbrick, I.A. and Blaber, M., Prot. Sci. 17, 1998-2007 (2008)   Kallikreins are Associated with Secondary Progressive Multiple Sclerosis and Promote Neurodegeneration, Scarisbrick, I.A., Linbo, R., Vandell, A.G., Keegan, M., Blaber, S.I., Blaber, M., Sneve, D., Lucchinetti, C.F., Rodriguez, M. and Diamandis, E., Biol. Chem. 389, 739-745 (2008)   The Substrate Specificity of Human Kallikrein 1 and 6 Determined by Phage Display, Li, H.-X., Hwang, B.-Y., Laxmikanthan, G., Blaber, S.I., Blaber, M., Golubkov, P.A., Ren, P., Iverson, B.L. and Georgiou, G., Prot. Sci. 17, 664-672 (2008)   A Logical OR Redundancy within the Asx-Pro-Asx-Gly Type I -turn Motif, Lee, J., Dubey, V.K., Longo, L.M. and Blaber, M., J. Mol. Biol. 377, 1251-1264 (2008)