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排序方式: 共有1319条查询结果,搜索用时 15 毫秒
1.
Reconstitution of protein translocation activity from partially solubilized microsomal vesicles 总被引:4,自引:0,他引:4
We have used a reconstitution assay to demonstrate that protein translocation activity can be recovered after microsomal vesicles derived from the rough endoplasmic reticulum have been partially solubilized with n-octyl-beta-glucopyranoside. Two independent approaches were used to establish conditions for partially solubilizing microsomal membranes. When the lipid bilayer was disrupted by detergents to the extent that the integrity of the lipid bilayer had been perturbed, membranes were inactive for translocation. However, detergent-treated membranes could be reconstituted in good yield into a translocation competent form once the detergent was removed. 相似文献
2.
Richard E. Kouri Raymond Kiefer Eugene M. Zimmerman 《In vitro cellular & developmental biology. Plant》1974,10(1-2):18-25
Summary Two methods for determining the hydrocarbon-metabolizing enzyme activity of cultured mammalian cells were compared. The method
designed to measure benzo[a]an-thracene-induced aryl hydrocarbon hydroxylase activity could detect and quantify enzyme activities
in low passage rodent cells, but could not reproducibly detect levels in intermediate or high passage mouse, rat, or human
cells. The method designed to measure the ability of a cell to convert benzo[a]pyrene from an organic-soluble to an aqueous
acetone-soluble form proved to be more reproducible. This technique, when modified, was demonstrated to be an effective screening
test for the detection of those lines with higher levels of hydrocarbon-metabolizing enzymes.
Supported by the Council for Tobacco Research and Contract NIH 70-2068 within the Virus Cancer Program, National Cancer Institute,
National Institutes of Health. 相似文献
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Conformational energy calculations using an empirical conformatinol energy program for peptides (ECEPP) werer carried out on 16 N-acetyl-N′-methylamides of Ser-X and X- Ser dipeptides, where X = Ala, Asn, Asn, Asp, Gly, Phe, Ser, Thr, and Val, and on Pro-Ser. As with the other dipeptides studied in this serites, intraresidue interactions found to dominate over interresidue interactions in determining conformational properties. The Ser-containing dipeptides (except for those with a pro or Gly residue) were found to have unusually low calculated bend probailities, in disagreement observations on proteins; this discrepancy probably arises becuse of sovent effects (not included in the computations). The Ser-X dipeptides were calculated to have a lower preference for bends than the X-Ser dipeptides. 相似文献
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Calcium-induced autolysis of bovine erythrocyte calpain I occurs in multiple stages. Initially, a 14 amino acid segment is cleaved from the N-terminus of the native 80 kDa catalytic subunit, yielding a 78 kDa form of the subunit. Then, an additional 12 amino acid segment is cleaved from the N-terminus, forming a 76 kDa subunit. The 76 kDa enzyme is the active form of the catalytic subunit that is able to proteolyze the 30 kDa regulatory subunit as well as exogenous substrates. While the initial autolytic step requires high calcium, the 76 kDa enzyme form is active in microM calcium and can cleave the amino termini of native 80 kDa and intermediate 78 kDa enzyme forms at low calcium. Both intramolecular and intermolecular proteolysis of the catalytic subunit appear to yield the same products. 相似文献