a constrained variables to obtain best fit
b ValUeS for high-affinity component
c values for low-affinity component


Table 3-1. Estimated kinetic parameters (Mean f SD) for (a) sulfonation and (b) glucuronidation of 3-OH-B[a]P by polar bear liver
 cytosol and microsomes. Values were calculated as described in the Methodology.


(a) sulfonation

Substrate Vmax1 (app)

 (pmol/min/mg)

3-OH-B[a]P 500 f 8

PAPS 162 f 35

(b) glucuronidation

Sub state Vmax (app)


Km (app)

(cLM)

0.41 f 0.03

0.22 f 0.07


Vmaxl/Km Vmax2 (app) a

(CIL/min/mg) (pmol/min/mg)

1220 f 70 65.0 f 20.0


Kz (app)

(cLM)

1.01 & 0.10


Vmax2/K,

(CLL/min/mg)

66.2 f 26.8


(nmol/min/mg)

3.00 f 1.18

1.53 f 0.56b, 1.47 f 0.48c


Km (app)

(cLM)

1.4 f 0.2

42.9 f 2.5b, 200 f 68c


Vmax/ Km

(CLL/min/mg)

1900 f 544


3 -OH-B [a]P

UDPGA