JOHN B. VINCENT

Research Interests

The elucidation of the structure, function, and mode of action of metallobiomolecules via: 1) spectroscopic, magnetic, kinetic and biochemical studies of the natural systems and 2) the synthesis and characterization of biomimetic inorganic complexes.

Our research applies biochemical and synthetic and physical inorganic methods to characterize the function and properties of metallobiomolecules (naturally occurring molecules such as proteins, sugars, etc. that contain tightly bound metal ions). The presence of the metal ions gives these species unique magnetic and spectroscopic properties (such as color) that provide avenues (not available to the study of simple proteins, etc.) by which we can examine these compounds in detail. Techniques involved include a variety of chromatographic methods; gel electrophoresis; mass spectrometry; electronic, Raman, electron spin resonance, IR, UV-visible, X-ray absorbance and nuclear magnetic resonance spectroscopies; and an assortment of synthetic methods.

Currently our efforts are focussed on the elucidation of the role of chromium in diabetes and the maintenance of proper carbohydrate and lipid metabolism and on the use of metalloprotein affinity metal chromatography.

We have recently shown that the oligopeptide chromodulin (or also known as low-molecular-weight chromium-binding substance, LMWCr) binds to insulin receptor in response to insulin; this results in an increase of the ability of insulin to signal cells that blood glucose concentrations are high. This may be related to adult-onset diabetes (90% of all diabetes cases in the United States), where body tissues become insensitive to insulin. We have also developed a synthetic biomimetic for chromodulin; this comple, called Cr₃, has been shown to lower total blood cholesterol levels in rats by 30% and LDL cholesterol by 40%, and may have potential in the treatment of the symptoms of adult-onset diabetes.

At present, it is extremely difficult to selectively remove metal ions from dilute aqueous solutions of mixed metal ions. Metalloprotein affinity metal chromatography uses Nature's own tricks for accomplishing this process to selectively remove and recover metal ions from waste streams. Current efforts are focussed on the removal of actinide ions (uranium, plutonium, etc.) using the metal transport protein transferrin covalently attached to chromatography supports.

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Representative Publications

"Effects of Pre- and Postnatal Exposure to Chromium Picolinate or Picolinic Acid on Neurological Development in CD-1 Mice." Bailey, M. M.; Boohaker, J. G.; Jernigan, P. L.; Townsend, M. B.; Sturdivant, J.; Rasco, J. F.; Vincent, J. B.; Hood, R. D. Biol. Trace Element Res. 124, 70-82 (2008).

"The effects of chromium(III) coordination on the dissociation of acidic peptides." Pu, D.; Vincent, J. B.; Cassady, C. J. J. Mass Spectrom. 43, 773-781 (2008).

"Nutritional supplement chromium picolinate generates chromosomal aberrations and impedes progeny development in Drosophila melanogaster." Stallings, D. M.; Hepburn, D. D. D.; Hannah, M.; Vincent, J. B.; O'Donnell, J. Mut. Res. 610, 101-113 (2006).

"High-dose chromium(III) supplementation has no effects on body mass and composition while altering plasma hormone and triglycerides concentrations." Bennett, R.; Adams, B.; French, A.; Neggers, Y.; Vincent, J. B. Biol. Trace Element Res. 113, 53-66 (2006).

"Oral administration of the biomimetic [Cr₃O(O₂CCH₂CH₃)₆(H₂O)₃]⁺ increases insulin sensitivity and improves blood plasma variables in healthy and type 2 diabetic rats." Clodfelder, B. J.; Gullick, B. M.; Lukaski, H. C.; Neggers, Y.; Vincent, J. B. J. Biol. Inorg. Chem. 10, 119-130 (2005).

"The time-dependent transport of chromium in adult rats from the bloodstream to the urine." Clodfelder, B. J.; Vincent, J. B. J. Biol. Inorg. Chem. 10, 383-393 (2005).

"Cytochrome c: A biochemistry laboratory course." Vincent, J. B.; Woski, S. A. J. Chem. Ed. 82, 1211-1214 (2005).

"A Comparison of the Insulin-Sensitive Transport of Chromium in Healthy and Model Diabetic Rats.” Clodfelder, B. J.; Upchurch, R. G.; Vincent, J. B. J. Inorg. Biochem. 98 (2004) 522-533.

"Nutritional supplement chromium picolinate causes sterility and lethal mutations in Drosophila melanogaster.” Hepburn, D. D. D.; Xiao, J.; Bindom, S.; Vincent, J. B.; O'Donnell, J.. Proc. Natl. Acad. Sci., USA, 100 (2003) 3766-3771.

"Characterization of Chromodulin by X-ray Absorption and Electron Paramagnetic Spectroscopies and Magnetic Susceptibility Measurements.” Jacquamet, L.; Sun, Y.; Hatfield, J.; Gu, W.; Cramer, S. P.; Crowder, M. W.; Lorigan, G. A.; Vincent, J. B.; Latour, J. M. J. Am. Chem. Soc. 125 (2003) 774-780.

Complete list of Dr. Vincent's publications (2/10/09)

The University of Alabama Department of Chemistry Faculty