Lageweg W, Tager J M, Wanders R J
Department of Pediatrics (FO-224), University of Amsterdam, The Netherlands.
Biochem J. 1991 May 15;276 ( Pt 1)(Pt 1):53-6. doi: 10.1042/bj2760053.
We have investigated the localization of palmitoyl-CoA (hexadecanoyl-CoA) synthetase (EC 6.2.1.3) and cerotoyl-CoA (hexacosanoyl-CoA) synthetase in peroxisomes isolated from rat liver. Palmitoyl-CoA and cerotoyl-CoA synthetases, like acyl-CoA: dihydroxyacetone phosphate acyltransferase (EC 2.3.1.42), are present in the peroxisomal membrane. Trypsin treatment of intact peroxisomes led to the disappearance of both palmitoyl-CoA and cerotoyl-CoA synthetase activities but had little, if any, effect on L-alpha-hydroxy-acid oxidase (EC 1.1.3.15), D-amino acid oxidase (EC 1.4.3.3) or acyl-CoA:dihydroxyacetone phosphate acyltransferase. The latter three enzymes were inactivated if the trypsin treatment was preceeded by disruption of the peroxisomes by sonication. These results show that the active site, or at least domains essential for the activity of cerotoyl-CoA synthetase, like that of palmitoyl-CoA synthetase, is located on the cytosolic face of the peroxisomal membrane.
我们研究了棕榈酰辅酶A（十六烷酰辅酶A）合成酶（EC 6.2.1.3）和蜡酰辅酶A（二十六烷酰辅酶A）合成酶在从大鼠肝脏分离出的过氧化物酶体中的定位。棕榈酰辅酶A和蜡酰辅酶A合成酶，与酰基辅酶A：磷酸二羟丙酮酰基转移酶（EC 2.3.1.42）一样，存在于过氧化物酶体膜中。用胰蛋白酶处理完整的过氧化物酶体导致棕榈酰辅酶A和蜡酰辅酶A合成酶活性均消失，但对L-α-羟酸氧化酶（EC 1.1.3.15）、D-氨基酸氧化酶（EC 1.4.3.3）或酰基辅酶A：磷酸二羟丙酮酰基转移酶几乎没有影响（如果有影响的话）。如果在胰蛋白酶处理之前先用超声破碎过氧化物酶体，则后三种酶会失活。这些结果表明，蜡酰辅酶A合成酶的活性位点，或者至少是对其活性至关重要的结构域，与棕榈酰辅酶A合成酶一样，位于过氧化物酶体膜的胞质面。
