Chang F N, Flaks J G
Proc Natl Acad Sci U S A. 1970 Nov;67(3):1321-8. doi: 10.1073/pnas.67.3.1321.
Treatment of Escherichia coli 30S ribosomal subunits with trypsin sequentially removes a number of different ribosomal proteins, as revealed by polyacrylamide gel electrophoresis. Proteins that are removed early by trypsin correlate well with those that are added last during reconstitutive assembly of the 30S subunit from 16S ribosomal RNA and the total protein complement. Proteins that are resistant to removal from the subunit by the highest trypsin concentration used correlate with those that are added early during assembly. Six proteins can be removed from the subunit with trypsin without affecting its ability to bind the antibiotic streptomycin. A decline in the ability of the 30S subunit to bind streptomycin is correlated with the removal of either one, or both, of two proteins, neither one of which is the gene product of the streptomycin locus. The implications of these findings for the topography and assembly of the 30S subunit are considered.
用胰蛋白酶处理大肠杆菌30S核糖体亚基,通过聚丙烯酰胺凝胶电泳发现,一系列不同的核糖体蛋白会依次被去除。早期被胰蛋白酶去除的蛋白质与在由16S核糖体RNA和总蛋白质组分重新组装30S亚基过程中最后添加的蛋白质高度相关。对所用最高胰蛋白酶浓度仍具有抗性、未从亚基中被去除的蛋白质与组装早期添加的蛋白质相关。六种蛋白质可以用胰蛋白酶从亚基中去除,而不影响其结合抗生素链霉素的能力。30S亚基结合链霉素能力的下降与两种蛋白质中一种或两种的去除相关,这两种蛋白质都不是链霉素位点的基因产物。本文考虑了这些发现对30S亚基的拓扑结构和组装的影响。