title: Stereoisomeric bio-inversion key to biosynthesis of firefly D-luciferin.
abstract: The chirality of the luciferin substrate is critical to the luciferin-luciferase reaction producing bioluminescence. In firefly, the biosynthetic pathway of D-luciferin is still unclear, although it can be synthesized in vitro from D-cysteine. Here, we show that the firefly produces both D- and L-luciferin, and that the amount of active D-luciferin increases gradually with maturation stage. Studies of firefly body extracts indicate the possible conversion of L-cysteine via L-luciferin into D-luciferin, suggesting that the biosynthesis is enzymatically regulated by stereoisomeric bio-inversion of L-luciferin. We conclude that the selection of chirality in living organisms is not as rigid as previously thought.
authors.affiliation: Research Institute for Cell Engineering, National Institute of Advanced Industrial Science and Technology, AIST, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Niwa
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ohmiya
mesh_terms: D000818:Animals; D048888:Fireflies / Q000737:chemistry / Q000254:growth & development*; D049454:Firefly Luciferin / Q000737:chemistry / Q000378:metabolism*; D013237:Stereoisomerism
chemical_list: D049454:Firefly Luciferin