TABLE 1.

Rate constants observed for the oxidation of the low spin hemes during oxidation of fully reduced NOR by NO

NO concentration	Rate constants	% of Total amplitude
		560 nm (heme b)	550 nm (heme c)
	s−1
1.5 mm NO, pH 7.5	50	10	50
	3	90	50
75 μm NO, pH 7.5	120	10	55
	12	90	45
1.5 mm NO, pH 6.0	150	∼10a	40
	6	∼90a	60
75 μm NO, pH 6.0	∼500	35	60
	100	65	40

^a Not detected at 560 nm, amount of heme b oxidized estimated from other wavelengths.