Fast Photochemical Oxidation Of Proteins Research Articles

Major circuit yield improvement: yours for the price of minor resistor redesign : Wayne Jacobs and Thomas T. Hitch. IEEE Trans. Components Hybrids mfg Technol.CHMT-5 (4), 388 (1982)

Hydroxyl radicals that react with cysteine (Cys), methionine (Met), tryptophan (Trp), tyrosine (Tyr), phenylalanine (Phe), and histidine (His) at nearly diffusion-limited reaction rates can be carried over into methods to footprint proteins. These residues are frequently found at protein–ligand interfaces, suggesting that reactions with OH radicals can be used to footprint protein–ligand interfaces. Success requires choosing the appropriate laser, reaction conditions, and concentration of scavenger. The early stages of the development of a method involving photochemical production of OH radicals by laser irradiation of a solution of protein containing small amounts of H2O2 included testing various laser wavelengths capable of homolytically cleaving H2O2 into hydroxyl radicals. This method is known as the fast photochemical oxidation of proteins (FPOP). Although a neodymium-doped yttrium aluminum garnet (Nd-YAG) 266-nm laser was able to generate a very small amount of oxidized protein, the use of 248-nm light from a krypton fluoride (KrF) laser resulted in substantial oxidation of the protein, strongly suggesting that this is a preferred wavelength at which to carry out FPOP. The approach is to irradiate the sample in a flow cell by timing the laser pulse frequency to the length of time required to pass a bolus or plug of sample completely through the flow cell.