Cat. No. : |
IFNA2-009N |
Description : |
At least 23 different variants of IFN-alpha are known. The individual proteins have molecular masses between 19-26 kDa and consist of proteins with lengths of 156-166 and 172 amino acids. All IFN-alpha subtypes possess a common conserved sequence region between amino acid positions 115-151 while the amino-terminal ends are variable. Many IFN-alpha subtypes differ in their sequences at only one or two positions. Naturally occurring variants also include proteins truncated by 10 amino acids at the carboxy-terminal end. |
Formulation : |
Lyophilized power, containing 80% SDS. |
Purity : |
Purity is assessed by SDS PAGE followed by Silver Stain Detection or Western blot analysis and by Capillary Electrophoresis using a 2100 Bioanalyzer. |
Quality analysis : |
Gel and capillary electrophoresis for estimation of purity. Mass spectrometry of tryptic digest products for identity determination. |
Amino acid sequence : |
The sequence of the first twelve N-terminal amino acids was determined and was found to be Cys-Asp-Leu-Pro-Gln-Thr-His-Ser-Leu-Gly-Ser-Arg, conforming to the sequence of native human-IFα-2a. Other protein fragments detected by mass spectroscopy of tryptic digestion are highlighted in red on the following sequence representation.CDLPQTHSLGSRRTLMLLAQMRKIS LFSCLKDRHDFGFPQEEFGNQFQKA ETIPVLHEMIQQIFNLFSTKDSSAA WDETLLDKFYTELYQQLNDLEACVI QGVGVTETPLMNEDSILAVRKYFQR ITLYLKEKKYSPCAWEVVRAEIMRS FSLSTNLQESLRSKE |
Endotoxin : |
< 0.0005 EU/µg by LAL test. |
Biological Activity : |
IFN-alpha 2a is fully biologically active when compared to standard. The specific activity was determined by a quantitative gene reported bioassay using human Type I interferon-sensitive cells. Compared with other recombinant IFα-2a, assayed in the same conditions, IFN-alpha 2a showed 6.1 × 108 Units/mg in reference to a viral resistance assay using bovine kidney MDBK cells. |
Storage : |
Product is presented as a lyophilized powder stable at 4°C. Adding 1 ml of distilled water to 1 mg of lyophilized powder gives a solution of 0.2 mg/ml of IFN Alpha-2a. After reconstitution in appropriate buffer aliquots should be stored at -70°C. |