T7 T7 RNA polymerase (1), partial, Escherichia phage, recombinant

Organism: Escherichia phage T7 (Bacteriophage T7). Source: E.coli. Expression Region: 710-805aa. Protein Length: Partial. Tag Info: N-terminal 6xHis-KSI-tagged. Target Protein Sequence: VKDKKTGEIL RKRCAVHWVT PDGFPVWQEY KKPIQTRLNL MFLGQFRLQP TINTNKDSEI DAHKQESGIA PNFVHSQDGS HLRKTVVWAH EKYGIE. Purity: Greater than 85% as determined by SDS-PAGE. Endotoxin: Not test. Biological Activity: n/a. Form: Liquid or Lyophilized powder. Buffer: If the delivery form is liquid, the default storage buffer is Tris/PBS-based buffer, 5%-50% glycerol. If the delivery form is lyophilized powder, the buffer before lyophilization is Tris/PBS-based buffer, 6% Trehalose, pH 8.0. Reconstitution: We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Please reconstitute protein in deionized sterile water to a concentration of 0.1-1.0 mg/mL.We recommend to add 5-50% of glycerol (final concentration) and aliquot for long-term storage at -20 °C/-80 °C. Our default final concentration of glycerol is 50%. Customers could use it as reference. Storage: The shelf life is related to many factors, storage state, buffer ingredients, storage temperature and the stability of the protein itself. Generally, the shelf life of liquid form is 6 months at -20 °C/-80 °C. The shelf life of lyophilized form is 12 months at -20 °C/-80 °C. Notes: Repeated freezing and thawing is not recommended. Store working aliquots at 4 °C for up to one week. Relevance: Highly processive DNA-dependent RNA polymerase that catalyzes the transcription of class II and class III viral genes. Recognizes a specific promoter sequence and enters first into an 'abortive phase' where very short transcripts are synthesized and released before proceeding to the processive transcription of long RNA chains. Unwinds the double-stranded DNA to expose the coding strand for templating. Participates in the initiation of viral DNA replication presumably by making primers accessible to the DNA polymerase, thus facilitating the DNA opening. Also plays a role in viral DNA packaging, probably by pausing the transcription at the right end of concatemer junction to allow packaging complex recruitment and beginning of the packaging process. Reference: "Lys631 residue in the active site of the bacteriophage T7 RNA polymerase. Affinity labeling and site-directed mutagenesis." Maksimova T.G., Mustayev A.A., Zaychikov E.F., Lyakhov D.L., Tunitskaya V.L., Akbarov A.K., Luchin S.V., Rechinsky V.O., Chernov B.K., Kochetkov S.N. Eur. J. Biochem. 195:841-847(1991). Function: nan