Entwistle Ruth A, Winefield Robert D, Foland Travis B, Lushington Gerald H, Himes Richard H
Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045-7534, USA.
FEBS Lett. 2008 Jul 9;582(16):2467-70. doi: 10.1016/j.febslet.2008.06.013. Epub 2008 Jun 18.
Previously, we created a paclitaxel-sensitive strain of Saccharomyces cerevisiae by mutating five amino acid residues in beta-tubulin in a strain that has a decreased level of the ABC multidrug transporters. We have used site-directed mutagenesis to examine the relative importance of the five residues in determining sensitivity of this strain to paclitaxel. We found that the change at position 19 from K (brain beta-tubulin) to A (yeast beta-tubulin) and at position 227 from H (brain beta-tubulin) to N (yeast beta-tubulin) had no effect on the activity of paclitaxel. On the other hand, the changes V23T, D26G and F270Y, drastically reduced sensitivity of AD1-8-tax to paclitaxel. Molecular modeling and computational studies were used to explain the results.
此前，我们通过在ABC多药转运蛋白水平降低的菌株中对β-微管蛋白的五个氨基酸残基进行突变，创建了一株对紫杉醇敏感的酿酒酵母菌株。我们利用定点诱变来研究这五个残基在确定该菌株对紫杉醇敏感性方面的相对重要性。我们发现，第19位从K（脑β-微管蛋白）变为A（酵母β-微管蛋白）以及第227位从H（脑β-微管蛋白）变为N（酵母β-微管蛋白）对紫杉醇的活性没有影响。另一方面，V23T、D26G和F270Y的变化极大地降低了AD1-8-tax对紫杉醇的敏感性。我们使用分子建模和计算研究来解释这些结果。
