Maturation of Sucrase-Isomaltase Complex in Human Fetal Small and Large Intestine during Gestation
Maturation of Sucrase-Isomaltase Complex in Human Fetal Small and Large Intestine during Gestation
复制标题
妊娠期间人胎儿小肠和大肠中蔗糖酶-异麦芽糖酶复合物的成熟
作者：
N. Triadou;A. Zweibaum
摘要：蔗糖酶-异麦芽糖酶复合物在整个妊娠期的人小肠和12 - 30周的大肠中表达。通过免疫印迹法研究了刷状缘膜组分中酶的分子形式。在妊娠30周之前，该酶仅作为高分子量的蔗糖酶原-异麦芽糖酶存在，而从30周直到出生，也存在两个亚基。胎儿酶，作为其前体和作为其两个亚基，在十二烷基硫酸钠聚丙烯酰胺凝胶电泳中具有比成人酶更快的迁移率（从胎儿酶中去除唾液酸残基强调了这种差异）。结肠和小肠的胎酶是相同的。
ABSTRACT: Sucrase-isomaltase complex is expressed in human small intestine throughout gestation and in the large intestine between 12 and 30 wk. The molecular form of the enzyme was studied in the brush-border membrane fractions by the immunoblotting method. Before 30 wk of gestation, the enzyme is present only as the high molecular weight prosucrase-isomaltase, while from 30 wk until birth the two subunits are also present. The fetal enzyme, as its proform and as its two subunits, has a faster mobility in sodium-dodecylsulfate polyacrylamide gel electrophoresis, than the adult enzyme (removal of sialic acid residues from fetal enzymes emphasizes this difference). The colonic and the small intestinal fetal enzymes are identical.