Patent attributes
Provided are mutant polymerases that comprise a deletion of at least four amino acids among the amino acids at positions corresponding to 167-174 of SEQ ID NO:1. Also provided are mutant polymerases having greater resistance to 30 mM NaCl, 7.5 mM phosphate, or 20 μg/ml single stranded DNA than a wild-type T7 RNA polymerase having SEQ ID NO:1 or a wild-type T3 RNA polymerase having SEQ ID NO:3. Nucleic acids comprising a nucleotide sequence encoding any of the above mutant polymerases are also provided, as are vectors comprising those nucleic acids and host cells transformed with the vectors Additionally, methods of amplifying mRNA using the mutant polymerases described herein are also provided. Further, compositions comprising any of the mutant polymerases described herein, and a reagent at a concentration that is inhibitory to wild-type T7 RNA polymerase is provided.
