Table 2.

O₂ affinity (P₅₀, torr; mean ±s.e.m.) and cooperativity coefficients (n₅₀) for purified hemolysates measured in 0.1 M Hepes buffer at pH 7.40, 37 °C, in the presence of the met-Hb reducing system (Hayashi et al., 1973). Measurements were conducted in the absence of DPG and KCl (stripped), and in the presence of DPG (DPG/Hb tetramer ratio = 2.0) or 0.1 M KCl, or both effectors. [Heme], 0.16 mM. N=3 replicate measurements for C57BL/6J, BALB/cJ, and MSM/Ms.

	C57BL/6J	BALB/cJ	MSM/Ms	CAROLI/EiJ
P50 (torr)
stripped	7.63±0.09	8.44±0.09	8.76±0.04	8.10
DPG	10.95±0.42	11.88±0.17	11.64±0.07	12.48
KCl	17.15±0.49	16.27±0.30	17.74±0.06	17.46
DPG+KCl	16.87±0.48	17.53±0.29	17.03±0.27	18.45
Δ log P50
DPG-stripped	0.16	0.15	0.12	0.19
KCl -stripped	0.35	0.29	0.31	0.33
(DPG+KCl) - stripped	0.34	0.31	0.29	0.36
(DPG+KCl) - KCl	−0.01	0.03	−0.02	0.02
(DPG+KCl) - DPG	0.19	0.17	0.17	0.17
n50
stripped	2.24±0.03	2.46±0.05	2.40±0.02	2.28
DPG	2.44±0.084	2.65±0.09	2.50±0.04	2.53
KCl	2.36±0.166	2.68±0.12	2.67±0.02	2.57
DPG + KCl	2.45±0.011	2.78±0.13	2.56±0.09	1.91