Targeted mutagenesis identifies Asp-569 as a catalytically critical residue in T7 RNA polymerase
✍ Scribed by Rechinsky, Vladimir O. ;Chernov, Boris K. ;Dragan, Sofia M. ;Kostyuk, Dmitry A. ;Tunitskaya, Vera L. ;Kochetkov, Sergey N.
- Book ID
- 104770528
- Publisher
- Springer
- Year
- 1995
- Tongue
- English
- Weight
- 423 KB
- Volume
- 247
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
✦ Synopsis
In order to look more closely at a wellconserved region in T7 RNA polymerase (T7 RNAP) containing, as shown earlier, the functionally essential residues Pro-563 and Tyr-571, we used targeted mutagenesis to change those residues within this region that are invariant in all single-subunit RNA polymerases, and characterized the mutant enzymes in vitro. The most interesting finding of this study was the crucial importance of the acidic group of Asp-569. In addition, we have shown that the phenolic ring is the most significant functional group of Tyr-571, with the hydroxy group also contributing to promoter binding.