Active Native Human C2 Protein

• Cat.No.: C2-98H

Specification

• Description: C2 is central to the activation of both the classical and the lectin pathways of complement. It forms the proteolytic subunit of the C3 and C5 convertase of both pathways. Initiation of each pathway generates proteolytic enzyme complexes which are bound to the target surface (C1q/C1r/C1s in the classical pathway and MBL/ Ficolin/ MASPs in the lectin pathway). C1s and MASP in these complexes activate both C4 and C2. They cleave a peptide bond in C4 depositing C4b on the surface. They also cleave C2 into two fragments. The larger fragment (C2a) binds to C4b and forms the C3/C5 convertase enzyme complex C4b,C2a. This enzyme activates C3, deposits C3b on or near the C4b,C2a site and thus is converted from a weak C5 convertase to a highly efficient C5 convertase (C4b,C2a,C3b) with a Km for C5 3000-fold lower than that of the C4b,C2a enzyme alone (Rawal N. and Pangburn M.K. (2003)).
• Source: Normal human serum (shown by certified tests to be negative for HBsAg and for antibodies to HCV, HIV-1 and HIV-II).
• Species: Human
• Form: Frozen liquid
• Bio-activity: >90% versus normal human serum standard (see Cert of Analysis)
• Molecular Mass: 93,000 Da (1 chain)
• Purity: >95% by SDS-PAGE
• Characteristic: Native human C2 is a naturally glycosylated polypeptide expressed as a 752 amino acid protein containing a 20 amino acid signal sequence. The mature protein contains 732 amino acids and is glycosylated at 8 potential sites all of which are N-linked sites (Morley, B.J. and Walport, M.J. (2000)). The calculated molecular weight of C2 is 81,000 daltons, but due to the high carbohydrate content (approximately 16%) it has been reported to run on reduced SDS-PAGE gels at a wide variety of apparent molecular weights. Depending on the SDS-PAGE system used C2 has been reported to appear as if it is 93,000, 102,000, 110,000, and 117,000 daltons. Upon cleavage of C2 by C1s or MASP two fragments are produced. The larger, C2a, with 509 amino acids forms the C3/C5 convertase of the classical and lectin pathways. C2a comes from the C-terminal of C2 while the smaller fragment, C2b, with 223 amino acids is from the N-terminal. Both contain carbohydrate. C2 has numerous allotypes (A, B, and C) and electrophoretic isoforms that can be separated by isoelectric focusing. The isoforms have pIs in the 6.0 to 6.3 pH range.
• Usage: For research use only. Not for human or drug use.
• Storage: -70°C or below. Avoid freeze/thaw.
• Concentration: 0.5 mg/ml (see Certificate of Analysis for exact conc.)
• Storage Buffer: 10 mM sodium phosphate, 145 mM NaCl, pH 6.0
• Preservative: None, 0.22 μm filtered.
• Warning: Use normal precautions for handling human blood products.
• Tag: Non

Gene Information

• Gene Name: C2 complement component 2 [ Homo sapiens ]
• Official Symbol: C2
• Synonyms: C2; complement component 2; complement C2; C3/C5 convertase; complement component C2; CO2; DKFZp779M0311
• Gene ID: 717
• mRNA Refseq: NM_000063
• Protein Refseq: NP_000054
• MIM: 613927
• UniProt ID: P06681
• Chromosome Location: 6p21.3
• Pathway: Activation of C3 and C5, organism-specific biosystem; Complement Activation, Classical Pathway, organism-specific biosystem; Complement and Coagulation Cascades, organism-specific biosystem; Complement and coagulation cascades, organism-specific biosystem; Complement and coagulation cascades, conserved biosystem; Complement cascade, organism-specific biosystem; Immune System, organism-specific biosystem
• Function: peptidase activity; serine-type endopeptidase activity