12th International Symposium on Bioluminescence & Chemiluminescence

Symposium abstracts:

Binding of flavin and aldehyde to the active site of bacterial luciferase

Lin, Leo Y-C., Szittner, R., Meighen, Edward. A.

Dept of Biochemistry, McGill University, Montreal, PQ, Canada.

Email:meighen@med.mcgill.ca

By anchoring the phosphate moiety of FMN and active flavin analogs to a phosphate binding site on the α subunit of luciferase and searching for a common orientation of the isoalloxazine ring, an unique conformation has been deduced for binding the flavin substrate in the active site of luciferase. Analyses of the properties of luciferases in which residues in close contact with the isoalloxazine ring have been mutated have now provided strong independent support for the location of flavin at this location. In particular, shifts in the color of the emitted light of luciferases in which residues on the re-face of the isoalloxazine ring have been mutated indicate that these residues may indeed be in close proximity to the flavin ring. Among these residues is Cys106 which closely approaches the pyrimidine portion of the isoalloxazine ring. Moreover, a spacious cavity or tunnel is present on the α subunit of bacterial luciferase next to the si-face of the flavin ring providing an ideal location for binding of oxygen and the long chain fatty aldehyde (Supported by grant MT4314 from the Canadian Institutes of Health Research [CIHR]).

Common features of the quorum sensing systems in Vibrio species

Miyamoto, Carol M., Skouris, N., Hosseinkhani, S., Lin, Leo C-Y., Meighen, Edward

This is a preprint of an article accepted for publication in Luminescence: Copyright 2001 John
Wiley & Sons, Ltd (Wiley website)