Harry A. Frank

Biological and Physical Chemistry

Professor
Associate Dean, College of Liberal Arts and Sciences
NIH Postdoctoral Fellow, University of California at Berkeley, 1977-80
Ph.D., Boston University, 1977
B.S., Memphis State University, 1972

Phone: 860-486-2844
Email : harry.frank@uconn.edu

Frank Group Home Page

Our research is focusing on the important class of biological pigments known as carotenoids. These are long-chain, conjugated, π-electron molecules, typified by β-carotene and lycopene, that provide an abundance of coloration in nature.

Carotenoids are unique in that their diversity of function is unmatched by any of the other class of naturally-occurring pigments. In humans, carotenoids play an important role as biological antioxidants against many chronic health disorders. In plants, algae, and photosynthetic bacteria, carotenoids operate efficiently in regulating photosynthetic energy transport and in protecting the systems from reactions with active oxygen species. Carotenoids also inhibit harmful reactions resulting from the photosynthetic apparatus being oversaturated with light.

The Roles of Carotenoids in Photosynthesis

There are many different roles carotenoids play in photosynthesis. These include: Light-harvesting, photoprotection, singlet oxygen scavenging, excess energy dissipation, protein structure stabilization, energy flow regulation, and redox function. A major goal of our research on carotenoids is to understand how these molecules are able to carry out these diverse functions. Information on the structures of carotenoids from X-ray and electron diffraction and nuclear magnetic resonance (NMR) techniques are being used to help pinpoint specific molecular features that control the photochemical and nonphotochemical processes in which carotenoids participate. Because it is not possible to deduce the mechanisms of the functions of carotenoids solely on the basis of their structures, information from molecular spectroscopic techniques that probe the dynamics and energetics of carotenoids are needed to augment the structural data. Hence, we are using absorption, fluorescence, fluorescence excitation, and ultrafast transient optical spectroscopy to elucidate the mechanisms of the reactions carotenoids undergo. In addition to the optical studies, magnetic resonance spectroscopy is being used in our lab to determine the structures, geometries, identities, and dynamics of carotenoids involved in photosynthetic energy transport and to determine the nature of their interactions with chlorophyll.