2ce2: Difference between revisions

We present a new design for a fluorescence microspectrophotometer for use, in kinetic crystallography in combination with x-ray diffraction, experiments. The FLUMIX device (Fluorescence spectroscopy to monitor, intermediates in x-ray crystallography) is built for 0 degrees, fluorescence detection, which has several advantages in comparison to a, conventional fluorometer with 90 degrees design. Due to the reduced, spatial requirements and the need for only one objective, the system is, highly versatile, easy to handle, and can be used for many different, applications. In combination with a conventional stereomicroscope, fluorescence measurements or reaction initiation can be performed directly, in a hanging drop crystallization setup. The FLUMIX device can be combined, with most x-ray sources, normally without the need of a specialized, mechanical support. As a biological model system, we have used H-Ras p21, with an artificially introduced photo-labile GTP precursor (caged GTP) and, a covalently attached fluorophore (IANBD amide). Using the FLUMIX system, detailed information about the state of photolyzed crystals of the, modified H-Ras p21 (p21(mod)) could be obtained. Measurements in, combination with a synchrotron beamline showed significant fluorescence, changes in p21(mod) crystals even within a few seconds of x-ray exposure, at 100 K.

2CE2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with MG, GDP and XY2 as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2CE2 OCA].  

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