Activity and stability of the luciferase--flavin intermediate

Area of Science:

• Biochemistry
• Microbiology
• Enzymology

Background:

• Bacterial bioluminescence is a light-producing process involving the enzyme luciferase.
• The key intermediate is formed from enzyme, reduced flavin mononucleotide (FMNH2), and oxygen.

Purpose of the Study:

• To investigate the properties of the luciferase intermediate under anaerobic conditions.
• To determine the relationship between the flavin chromophore and bioluminescence yield.

Main Methods:

• Formation of the luciferase intermediate under specific reaction conditions.
• Anaerobic incubation of the intermediate with aldehyde.
• Spectroscopic analysis of the flavin chromophore (absorption maximum at ~370 nm).

Main Results:

• The luciferase intermediate emits light upon addition of aldehyde anaerobically.
• The reaction of the intermediate with oxygen is effectively irreversible.
• Bioluminescence yield is directly proportional to the flavin chromophore concentration.

Conclusions:

• The isolated luciferase intermediate is capable of light emission with aldehyde.
• The flavin chromophore concentration is a critical determinant of bioluminescence potential.