Activity of purified biosynthetic proteinase of human immunodeficiency virus on natural substrates and synthetic peptides.

AUTOR(ES)

Kräusslich, H G

RESUMO

Retroviral capsid proteins and replication enzymes are synthesized as polyproteins that are proteolytically processed to the mature products by a virus-encoded proteinase. We have purified the proteinase of human immunodeficiency virus (HIV), expressed in Escherichia coli, to approximately 90% purity. The purified enzyme at a concentration of approximately 20 nM gave rapid, efficient, and specific cleavage of an in vitro synthesized gag precursor protein. Purified HIV proteinase also induced specific cleavage of five decapeptide substrates whose amino acid sequences corresponded to cleavage sites in the HIV polyprotein but not of a peptide corresponding to a cleavage site in another retrovirus. Competition experiments with different peptides allowed a ranking of cleavage sites. Inhibition studies indicated that the HIV proteinase was inhibited by pepstatin A with an IC50 of 0.7 microM.

Documentos Relacionados

• Cleavage specificity of purified recombinant hepatitis A virus 3C proteinase on natural substrates.
• Type-specific neutralization of the human immunodeficiency virus with antibodies to env-encoded synthetic peptides.
• Lack of tuberculin activity of synthetic peptides.
• Poliovirus proteinase 3C: large-scale expression, purification, and specific cleavage activity on natural and synthetic substrates in vitro.
• Interactions of Neisseria gonorrhoeae with human neutrophils: studies with purified PII (Opa) outer membrane proteins and synthetic Opa peptides.