"Photo" Chemistry Without Light?

AUTOR(ES)

Baader, Wilhelm J., Stevani, Cassius V., Bechara, Etelvino J. H.

FONTE

J. Braz. Chem. Soc.

DATA DE PUBLICAÇÃO

2015-12

RESUMO

In the early seventies, Giuseppe Cilento (São Paulo University), Emil White (Johns Hopkins University) and Angelo Lamola (AT&T Bell Laboratories) postulated that typical photochemical reactions could occur in dark parts of living organisms if coupled to enzymatic sources of electronically excited products. Their paradoxical hypothesis of "photochemistry without light" was chemically anchored on the synthesis and weak chemiluminescence of several 1,2-dioxetanes, unstable cyclic peroxides whose thermal cleavage produces long-lived and reactive triplet carbonyls. Collisional reactions or energy transfer of triplet species to cellular targets could eventually result in "photo" products that potentially trigger normal or pathological responses. These ideas flourished in the labs of various researchers who attempted to explain the presence and biological roles of "dark" secondary metabolites, including plant hormones, pyrimidine dimers, alkaloid lumi-isomers, protein adducts, and mitochondrial permeators, thereby broadening the field of photobiology.

Documentos Relacionados

• Sarcoidosis--a gleam of light?
• Where is the light? Bayesian perceptual priors for lighting direction
• More sweetness than light? A search for the causes of diabetic vasculopathy
• Shedding Light on Chemistry
• Investigation of Mg2+- and temperature-dependent folding of the hairpin ribozyme by photo-crosslinking: effects of photo-crosslinker tether length and chemistry