COMPUTER-ANALYSIS OF CORRELATION BETWEEN BIOLUMINESCENCE SPECTRA MAXIMUM AND PRIMARY STRUCTURE OF BEETLE LUCIFERASE - IDENTIFICATION OF SITES RESPONSIBLE FOR COLOR CHANGES

Statistical analysis of correlation between the color of bioluminescen ce and amino acid substitutions in beetle luciferase was carried out u sing ProAnalyst software. We analyzed a number of click beetle lucifer ase sequences (four wild-type enzymes and 27 hybrids) together with th e bioluminescence spectral maxima (nu(max)) of these proteins. Ninety percent of nu(max) changes resulted from amino acid substitutions affe cting positions 223 or 238 (which are fully correlated) coupled with s ingle substitution at either 247, 352, or 358 positions. Click beetle nu(max) directly changed with the total ''polarizability'' of amino ac ids 223-224 and 227 (major contribution) and 351-352 (minor contributi on). We suggest that these regions are close to the emitter.