NOVEL CONFOCAL LASER SCANNING MICROSCOPY APPROACHES IN CRYSTALLOGENESIS

Peter Mühlig, Rolf Hilgenfeld

Institute of Molecular Biotechnology, Department of Structural Biology and Crystallography, Beutenbergstr. 11, D-07745 Jena, Germany, e-mail: pmuehlig@imb-jena.de

The microscopic methods of polarization contrast and 3D confocal microscopy in the reflection light and in the dark field modus were applied to study microcrystals of concanavaline A, hen egg-white lysozyme, Mip protein and coagulation factor XIII. Much larger inhomogeneities than detectable by classical microscopic methods were visible using advanced high-resolution confocal microscopy, both on the surface of and inside the crystals. In some cases, globular structures of 100 nm size were found to alternate with homogeneous regions that could be detected by interference fringes. Further developments of the method and their application to crystallogenesis will be discussed.