Biotransformation of Cholesterol and 16α,17α-Epoxypregnenolone and Isolation of Hydroxylase in Burkholderia cepacia SE-1

Table 1

Purification of the cholesterol 7β-hydroxylase from Burkholderia cepacia SE-1.

Step	Volume (mL)	Total protein (mg)	Total activity (U)	Specific activity (U/mg)	Purification (fold)	Yield (%)
Ammonium sulfate	10	35.77	456.50	12.76	1.0	100.00
DEAE-cellulose	20	15.86	218.21	13.76	1.1	47.80
Sephadex G-200	10	5.76	107.69	18.70	1.5	23.59
PAGE	0.5	0.58	21.59	37.22	2.9	4.73

Protein concentration was determined by the method of Bradford [16] with bovine serum albumin as the standard.
Cholesterol 7β-hydroxylase activity was assayed by measuring the quantity of 7β-cholesterol.
PAGE: polyacrylamide gel electrophoresis.