THE YELLOW BIOLUMINESCENCE BACTERIUM, VIBRIO-FISCHERI Y1, CONTAINS A BIOLUMINESCENCE ACTIVE RIBOFLAVIN PROTEIN IN ADDITION TO THE YELLOW FLUORESCENCE FMN PROTEIN

The yellow bioluminescence Y1 strain of Vibrio fischeri can produce a 22 kDa protein with either FMN or riboflavin as a bound fluorophore. B oth forms are active for shifting the bioluminescence spectral maximum . The fluorescence spectral distribution of the two proteins differs s lightly and the in vivo emission appears to be an equal mixture of the two. The bioluminescence activity of the riboflavin Y1 protein contra sts with the inactivity of the related Photobacterium type. (C) 1995 A cademic Press, Inc.