Reaction catalyzed by gamma-glutamylcyclotransferase (4.3.2.9)

		=			+
	N5-((S)-1-carboxy-3-(ethyl(((3-oxo-3H-phenoxazin-7-yl)oxy)carbonyl)amino)propyl)-L-glutamine	=		(2S)-2-amino-4-(ethyl[[(3-oxo-3H-phenoxazin-7-yl)oxy]carbonyl]amino)butanoic acid	+		5-oxo-L-proline