Inactivation of human liver arginase by Woodward's reagent K: Evidence for reaction with His141

Carvajal N.; Uribe, E; López, V.; Salas, M

Abstract

Human liver arginase (EC 3.5.3.1) was totally inactivated by incubation with Woodward's reagent K (WRK). The inactivation followed pseudo-first-order kinetics, and the order of the inactivation was close to 1, consistent with reaction of one molecule of WRK with one subunit molecule for inactivation. The effect was totally reversed by 0.5 M hydroxylamine, and reactivated species were inactivated again by a second incubation with WRK. The pH dependence of the pseudo-first-order rate constants of inactivation indicated the participation of a ionizable residue with a pKa of 6.3 at 25°C. Replacement of His141 with phenylalanine rendered the enzyme totally resistant to the inactivation. We conclude that His141 is the residue whose chemical modification with WRK inactivates the enzyme. © 2004 Plenum Publishing Corporation.

Más información

Título según WOS: Inactivation of human liver arginase by Woodward's reagent K: Evidence for reaction with His141
Título según SCOPUS: Inactivation of human liver arginase by Woodward's reagent K: Evidence for reaction with His141
Título de la Revista: PROTEIN JOURNAL
Volumen: 23
Número: 3
Editorial: Springer
Fecha de publicación: 2004
Página de inicio: 179
Página final: 183
Idioma: English
URL: http://link.springer.com/10.1023/B:JOPC.0000026413.68088.e0
DOI:

10.1023/B:JOPC.0000026413.68088.e0

Notas: ISI, SCOPUS