30S ribosomal protein S4 (rpsD), Escherichia coli, recombinant

Organism: Escherichia coli (strain K12). Source: E.coli. Expression Region: 2-206aa. Protein Length: Full Length of Mature Protein. Tag Info: N-terminal 6xHis-tagged. Target Protein Sequence: ARYLGPKLKL SRREGTDLFL KSGVRAIDTK CKIEQAPGQH GARKPRLSDY GVQLREKQKV RRIYGVLERQ FRNYYKEAAR LKGNTGENLL ALLEGRLDNV VYRMGFGATR AEARQLVSHK AIMVNGRVVN IASYQVSPND VVSIREKAKK QSRVKAALEL AEQREKPTWL EVDAGKMEGT FKRKPERSDL SADINEHLIV ELYSK. Purity: Greater than 90% 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: One of two assbly initiator proteins for the 30S subunit, it binds directly to 16S rRNA where it nucleates assbly of the body of the 30S subunit.With S5 and S12 plays an important role in translational accuracy, many suppressors of streptomycin-dependent mutants of protein S12 are found in this protein, some but not all of which decrease translational accuracy (ram, ribosomal ambiguity mutations).Plays a role in mRNA unwinding by the ribosome, possibly by forming part of a processivity clamp.Protein S4 is also a translational repressor protein, it controls the translation of the alpha-operon (which codes for S13, S11, S4, RNA polymerase alpha subunit, and L17) by binding to its mRNA.Also functions as a rho-dependent antiterminator of rRNA transcription, increasing the synthesis of rRNA under conditions of excess protein, allowing a more rapid return to homeostasis. Binds directly to RNA polymerase. Reference: Nucleotide sequence of the alpha ribosomal protein operon of Escherichia coli.Bedwell D.M., Davis G.R., Gosink M., Post L.E., Nomura M., Kestler H., Zengel J.M., Lindahl L.Nucleic Acids Res. 13:3891-3903(1985). Function: One of two assembly initiator proteins for the 30S subunit, it binds directly to 16S rRNA where it nucleates assembly of the body of the 30S subunit.