Photosynthetic Reaction Centers: Interfacing Molecular Genetics and
Optical Spectroscopy
Youvan D.C.
Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.
In the elucidation of the mechanism by which certain photosynthetic bacteria convert light
into chemical energy, genetics has become intertwined with biophysical techniques. While
X-ray crystallography has yielded an atomic resolution structure of the photosynthetic
reaction center (RC), optical spectroscopy remains the most important technique for
screening mutants. Newly developed imaging devices and genetic techniques should enable
biophysicists to characterize rapidly the spectra of extremely large numbers of RC and
light harvesting (LH) antennae mutants. The intrinsic pigments of the RC and LH antennae
act as spectroscopic reporters for assembly and function of these integral membrane
proteins. To optimize this genetics/spectroscopy interface, new algorithms that relate the
structure of the genetic code to the physico-chemical properties of the amino acids are
being developed to design libraries of mutants.