HCV-NS3His protein.The protein contains the full-length HCV NS3 (c33c) immunodominant regions and carries a His6-Tag. No fusionsequences.Hepatitis C NS3 protein is purified by proprietarychromatographic techniques.The nonstructural protein NS3 of the hepatitis C virus(HCV) is indispensable for virus replication and a multifunctional enzyme that contains three catalytic activitiessuch as serine protease, helicase, and NTPase. The Nterminal domain of the protein contains protease activity and the C-terminal domain contains nucleotide triphosphatase and RNA helicase activity.It has been shown that NS2/3 cleavage is mediated byNS2-3 protease, whereas NS3 serine protease is responsible for the other four cleavage sites of the nonstructural(NS) region. Immunoblot analysis on serum samples from90 patients with chronic hepatitis C virus infection revealed four putative immunogenic regions within the NS3protein of the virus: E (around amino acids 1250/1251),A (within amino acids 1250-1334), A/B (around aminoacids 1323 and 1334), and B/C (around amino acids1407 and 1412). Among them, region E was most immunodominant, and region A was recognized much lessfrequently by patients with cirrhosis than by those withchronic hepatitis. MW: 26 kDa. Purity >95% by SDS-PAGE