BLABER LAB RESEARCH
Proteins are the "workhorse" molecules of living systems, providing both the structural elements of cells and tissues, as well as the molecular machinery enabling the myriad and complex functions of living systems. Natural and engineered recombinant proteins provide for novel biopharmaceuticals, and proteins are now the fastest-growing category of new drug approvals by the FDA. 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. However, the field of engineered protein biopharmaceuticals has barely been tapped. There remain major difficulties in exploiting protein biopharmaceuticals - related to protein folding, misfolding,and aggregation. Biophysical studies into these areas (an emphasis in the Blaber Lab) can make a significant contribution to the successful realization of protein biopharmaceuticals.
Basic scientific studies of protein structure and biophysical properties allow us to form hypotheses regarding the molecular basis of protein folding and 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.
Protein folding, evolution and design are closely-related areas. Research in the Blaber Lab has also focused upon the evolutionary means by which complex protein architecture might have emerged from simpler peptide motifs. Structural symmetry is a key contributor to such evolutionary processes, resulting from gene duplication and fusion events. The large number of symmetric protein folds in the proteome support this hypothesis; however, gene duplication and fusion processes represent major errors in replication. Such errors are typically considered lethal events, so clearly there are hidden advantagees to symmetric protein architecutres that are poorly understood. Our research is focused upon the consequences of multiple folding nuclei that would occur in such evolutionary processes, and their ability to provide for redundant protein folding (thereby providing a potential selective advantage).
Research Skill Set
Students in the Blaber Lab can gain technical experience in the following areas:
Protein Chemistry, Biophysics and Structural Biology
Expression of recombinant proteins (prokaryotic and eukaryotic hosts)
Purification of recombinant proteins (including liquid chromatography)
Isothermal equilibrium denaturation
Differential scanning calorimetry (DSC)
Isothermal titration calorimetry (ITC)
Circular dichroism (CD)
X-ray crystal structure determination
Current Research Projects
"SECOND GENERATION" FORMS OF HUMAN FIBROBLAST GROWTH FACTOR-1 (FGF-1) AS A BIOTHERAPEUTIC IN REGENERATIVE MEDICINE
FGF-1 is a potent mitogen and chemotactic agent for a variety of cells including vascular endothelial cells (i.e. creating new blood vessels), fibroblasts and keratinocytes (forming new skin), and a variety of other cells associated with "regenerative medicine". FGF-1 also has a poorly-understood and novel blood glucose lowering activity. Our lab has published work showing that topical FGF-1 can accelerated wound healing in diabetic mice; other groups have reported related applications in other disease states (such as vascular and cardiac disease); still other reports show FGF-1 can accelerate corneal healing. Such studies suggest that FGF-1 can be used as a new type of biopharmaceutical in the broad area of regenerative medicine; however, FGF-1 has biophysical properties of poor stability and aggregation that complicate its effective application as a drug. We are developing novel forms of FGF-1 with enhanced properties for human therapies. The lab currently has 15 issued patents related to designed FGF-1 mutants with enhanced properties, and a number of these patents have been licenced to further their development as a human therapeutic agent.
SYMMETRY IN PROTEIN EVOLUTION AND DESIGN
Symmetry is a poorly-understood area of protein evolution and design. Although it was widely acknowledged that common symmetric protein architectures (such as the TIM-barrel) most likely evolved through a process of gene duplication and fusion, it was also widely held that purely-symmetric primary structure would frustrate efficient folding. Since gene duplication and fusion would initially yield symmetric primary structure, the above two postulates are logically inconsistent. Our lab reported the first successful design of a cooperatively-folding and thermostable purely-symmetric protein (the "Symfoil" protein). Since then, four other groups have reported successful such designs, involving three different types of protein folds. We have postulated that the folding nucleus is the critical heritable element in gene duplication and fusion evolutionary processes. This leads to the additional postulate that such symmetric proteins have multiple, and possibly overlapping, folding nuclei. Such nuclei might provide redundant folding pathways - enabling diverse deleterious mutations to nonetheless fold (thus, providing a selective advantage). Such behavior can suggest efficient de novo protein strategies. The lab is thus contributing to a basic understanding of important aspects of protein evolution and design.
Publications and Funding
A complete listing of reseearch publications and funding of the Blaber Lab can be found in Dr. Michael Blaber's cv (the link is here).
Here are some examples of proteins whose x-ray structure has been solved by the Blaber lab (click on image to explore structure):
3049(Symfoil, the first thermostable and cooperativley-folding purely-symmetric designed protein)
2AFG (the first x-ray structure of human acidic fibroblast growth factor; the broadest-specificity human mitogen known)
1RG8 (an atomic (1.1Å) x-ray structure of human acidic fibroblast growth factor; used to understand correlated molecular motions)
1L06 (the first x-ray structure depostited for a human kallikrein; hK6, or myelencephalon-specific protease)
1A80 (the first x-ray structure of a prokaryotic aldo-keto reductase; 2,5-diketo-D-gluconate reductase)
1HW6 (the first structure demonstrating NADPH-induced active site organization in an aldo-keto reductase)