Staphylococcal protein A is a novel heterologous substrate for the HIV-1 protease.
Upon in vitro processing of the recombinant HIV-1/gag p24 protein, expressed in Escherichia coli as a fusion protein, by HIV-1 protease, a cleavage site within the staphylococcal protein A fusion partner was found. N-terminal sequencing of the protein A fragments showed that HIV-1 protease cleavage occurred between phenylalanine-235 and tyrosine-236 within the sequence Gln-Asn-Ala-Phe/Tyr-Glu-Ile-Leu (QNAF/YEIL) in the IgG-binding domain C of the protein A encoded by the pRIT2T fusion gene vector (Pharmacia). Results presented here have proven that the protease-sensitive site is viable in vitro on the protein A alone and other chimeric protein, protein A/beta-galactosidase. A possible significance of this phenomenon in biotechnology work is discussed.
Marczinovits
I
I
Institute of Microbiology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Molnár
J
J
Patthy
A
A
D000595:Amino Acid Sequence; D001665:Binding Sites; D004591:Electrophoresis, Polyacrylamide Gel; D016333:HIV Protease / Q000378:metabolism*; D015497:HIV-1; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D010957:Plasmids; D013205:Staphylococcal Protein A / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity
D010446:Peptide Fragments; D013205:Staphylococcal Protein A; D016333:HIV Protease