Micro-spectrophotometry is proving to be an important tool for assessing the catalytic properties of enzymes in the crystal (Bourgeois et al., 2002Pearson et al., 2007). It can be applied to metallo-enzymes, photosensitive proteins or proteins with co-factors, substrates or products that absorbs in UV-VIS. Micro-spectrophotometry can be used to confirm the presence or absence of a substrate or a co-factor, as well as the redox state of a protein. It can also aid the design of efficient triggering of a reaction in the crystals or trapping of intermediate states.

BioCARS micro-spectrophotometer is available to users for crystal absorption measurements as a stand-alone instrument for off-line measurements. We use modified 4DX XSPECTRA micro-spectrophotometer system.


  • Bourgeois, D., Vernede, X., Adam, V., Fioravanti, E., and Ursby, T.  A microspectrophotometer for UV-visible absorption and fluorescence studies of protein crystals.  Journal of Applied Crystallography 35, 319-326 (2002) abstract
  • Pearson, A.R., Pahl, R., Kovaleva, E.G., Davidson, V.L., and Wilmot, C.M.  Tracking X-ray-derived redox changes in crystals of a methylamine dehydrogenase/amicyanin complex using single-crystal UV/Vis microspectrophotometry.  Journal of Synchrotron Radiation 14, 92-98 (2007) abstract

Facility Contacts

Robert Henning

Research Beamline Scientist
(630) 252-0446

Irina Kosheleva

Research Beamline Scientist
(630) 252-0467