TY - JOUR
T1 - Selective oxidation of tyrosine-Oxidation by NO2 and ClO2 at basic pH
AU - Alfassi, Zeev B.
N1 - Funding Information:
In the pulse radiolysiso f solutionso f NaNO: + tyrosine the usual spectrumo f the tyrosine radical was obtaineds, imilarto that in Fig. I. On the other hand, no spectrums imilar to that in Fig. 2 was obtainedin the reactiono f CIO2 with tryptophanA. n upper limit for the rate constantf or the reactiono f NO2 + tryptophani s 5 x 105M - ~s - ~, an accurate rate constanct annotb em easureddu eto the decayo f Acknowledgement--The researcdhe scribehde reinw as supported by the Office of Basic Energy Scienceso f the Departmenotf EnergyT. his is DocumenNt o. NDRL 2821.
PY - 1987/1/1
Y1 - 1987/1/1
N2 - This study, using chlorine dioxide and nitrogen dioxide as oxidants, was carried out in basic aqueous solutions of the free amino acids, purged of oxygen and saturated with N//2O to convert hydrated electrons to hydroxyl radicals. The solutions were irradiated with 5 ns electron pulses from an ARCO LP-7 linear accelerator. Chlorine dioxide was produced by using solutions of NaClO//2, and nitrogen dioxide was produced similarly from NaNO//2 solutions. ClO//2 radicals were found to oxidize both tryptophan and tyrosine. The rates for the reaction of ClO//2 plus amino acid were studied from the first-order build-up of these spectra over a four- to five-fold concentration range of the amino acid. The rates were found to be proportional to the amino acid concentration. From these dependencies the rate constants for the reaction of ClO//2 with tyrosine and tryptophan are found.
AB - This study, using chlorine dioxide and nitrogen dioxide as oxidants, was carried out in basic aqueous solutions of the free amino acids, purged of oxygen and saturated with N//2O to convert hydrated electrons to hydroxyl radicals. The solutions were irradiated with 5 ns electron pulses from an ARCO LP-7 linear accelerator. Chlorine dioxide was produced by using solutions of NaClO//2, and nitrogen dioxide was produced similarly from NaNO//2 solutions. ClO//2 radicals were found to oxidize both tryptophan and tyrosine. The rates for the reaction of ClO//2 plus amino acid were studied from the first-order build-up of these spectra over a four- to five-fold concentration range of the amino acid. The rates were found to be proportional to the amino acid concentration. From these dependencies the rate constants for the reaction of ClO//2 with tyrosine and tryptophan are found.
UR - http://www.scopus.com/inward/record.url?scp=50849151003&partnerID=8YFLogxK
U2 - 10.1016/1359-0197(87)90014-2
DO - 10.1016/1359-0197(87)90014-2
M3 - Article
SN - 1359-0197
VL - 29
SP - 405
EP - 406
JO - International Journal of Radiation Applications and Instrumentation. Part
JF - International Journal of Radiation Applications and Instrumentation. Part
IS - 5
ER -