Table A2. Parameter values Parameter... | Rockefeller University Press

Table A2.

Parameter values

Parameter values for Ca²⁺ pumps				Rate constants for buffers and diffusion		Concentrations		Rate constants for leaks
Parameter	SERCA	PMCA	Units	Rate constants for buffers and diffusion		Concentrations		Rate constants for leaks
$k_{1}^{+}$	25.9		μM⁻¹ s⁻¹	$k_{o n}^{B} / k_{o f f}^{B}$	1.55 × 10⁻⁶ μM⁻¹ s⁻¹/3,000 s⁻¹
$k_{2}^{+}$	2,540		μM⁻¹ s⁻¹	$k_{o n}^{E G T A} / k_{o n}^{E G T A}$	1.67 μM⁻¹ s⁻¹/0.31 s⁻¹
$k_{3}^{+}$	23.6		μM⁻¹ s⁻¹	$k_{d i f f}$	2.8 × 10⁴ s⁻¹
$k_{1}^{-}$	51.8		s⁻¹
$k_{2}^{-}$	67.2		s⁻¹			[ATP]	8 × 10³ μM
$k_{3}^{-}$	0.149		s⁻¹			[ADP]	5 μM
$K_{d, C a i}$ ^*	3,540	180	μM			[Pi]	1 × 10³ μM
$K_{{d, C a}_{S R}}$	2,240		μM			pH/[H⁺]	7.1/0.0794
$K_{d, H 1}$	0.0109		μM
$K_{{d, H}_{i}}$	3,540		μM					$k_{L e a k}^{T}$	Values determined as described in text
$K_{{d, H}_{S R}}$	0.0105		μM					$k_{L e a k}^{R Y R}$
$K_{d, H}$	0.0724		μM					$k_{L e a k}^{S R}$
[pump]	59	58	μM
n_Ca	2

Parameter values for Ca²⁺ pumps				Rate constants for buffers and diffusion		Concentrations		Rate constants for leaks
Parameter	SERCA	PMCA	Units	Rate constants for buffers and diffusion		Concentrations		Rate constants for leaks
$k_{1}^{+}$	25.9		μM⁻¹ s⁻¹	$k_{o n}^{B} / k_{o f f}^{B}$	1.55 × 10⁻⁶ μM⁻¹ s⁻¹/3,000 s⁻¹
$k_{2}^{+}$	2,540		μM⁻¹ s⁻¹	$k_{o n}^{E G T A} / k_{o n}^{E G T A}$	1.67 μM⁻¹ s⁻¹/0.31 s⁻¹
$k_{3}^{+}$	23.6		μM⁻¹ s⁻¹	$k_{d i f f}$	2.8 × 10⁴ s⁻¹
$k_{1}^{-}$	51.8		s⁻¹
$k_{2}^{-}$	67.2		s⁻¹			[ATP]	8 × 10³ μM
$k_{3}^{-}$	0.149		s⁻¹			[ADP]	5 μM
$K_{d, C a i}$ ^*	3,540	180	μM			[Pi]	1 × 10³ μM
$K_{{d, C a}_{S R}}$	2,240		μM			pH/[H⁺]	7.1/0.0794
$K_{d, H 1}$	0.0109		μM
$K_{{d, H}_{i}}$	3,540		μM					$k_{L e a k}^{T}$	Values determined as described in text
$K_{{d, H}_{S R}}$	0.0105		μM					$k_{L e a k}^{R Y R}$
$K_{d, H}$	0.0724		μM					$k_{L e a k}^{S R}$
[pump]	59	58	μM
n_Ca	2

$K_{{d, C a}_{i}}$ in Fig. A1 corresponds to $K_{D}^{S E R C A}$ and $K_{D}^{P M C A}$ for SERCA and PMCA, respectively. $k_{3}^{+}$ was adjusted to match experimentally determined pump turnover (6 s⁻¹); $K_{{d, C a}_{i}}$ was adjusted to match the observed Ca₅₀ values; other parameter values for Ca²⁺ pumps were as determined by Tran et al. (2009).

View Large

This Feature Is Available To Subscribers Only