Complement factor I (CFI), partial, human, recombinant

Organism: Homo sapiens (Human). Source: E.coli. Expression Region: 239-316aa. Protein Length: Partial. Tag Info: N-terminal 10xHis-GST-tagged and C-terminal Myc-tagged. Target Protein Sequence: KACDGINDCG DQSDELCCKA CQGKGFHCKS GVCIPSQYQC NGEVDCITGE DEVGCAGFAS VTQEETEILT ADMDAERR. 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: Trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. Inhibits these pathways by cleaving three peptide bonds in the alpha-chain of C3b and two bonds in the alpha-chain of C4b thereby inactivating these proteins . Essential cofactors for these reactions include factor H and C4BP in the fluid phase and membrane cofactor protein/CD46 and CR1 on cell surfaces . The presence of these cofactors on healthy cells allows degradation of deposited C3b by CFI in order to prevent undesired complement activation, while in apoptotic cells or microbes, the absence of such cofactors leads to C3b-mediated complement activation and subsequent opsonization . Reference: "Regulator-dependent mechanisms of C3b processing by factor I allow differentiation of immune responses." Xue X., Wu J., Ricklin D., Forneris F., Di Crescenzio P., Schmidt C.Q., Granneman J., Sharp T.H., Lambris J.D., Gros P. Nat. Struct. Mol. Biol. 24:643-651(2017). Function: nan