IFN alpha 2b, Interferon alpha 2b (E. coli-derived), human: 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., UnitProt ID: P01563