Document 0027
 DOCN  M9650027
 TI    HIV-1 protease specificity derived from a complex mixture of synthetic
       substrates.
 DT    9605
 AU    Kassel DB; Green MD; Wehbie RS; Swanstrom R; Berman J; Glaxo-Wellcome
       Research Institute, Research Triangle Park, North; Carolina 27709, USA.
 SO    Anal Biochem. 1995 Jul 1;228(2):259-66. Unique Identifier : AIDSLINE
       MED/96171046
 AB    A rapid and semiquantitative method is described for determining the
       relative kcat/Km for individual peptides in defined substrate mixtures.
       The method utilizes electrospray ionization/mass spectrometry alone to
       semiquantitatively determine relative peptide substrate turnover rates.
       Unlike previous studies, in which chromatographic separation of
       individual peptide species was required, this mass spectrometric-based
       method relies strictly on the ability to ionize and detect
       simultaneously all peptide species in a defined mixture. Differences in
       the ion intensities of the individual components before and after
       incubation with protease are used to semiquantitatively determine
       preferred substrates. This method was used to the identify preferred
       peptide substrates for HIV-1 protease. Optimal substrates were
       identified from a defined synthetic peptide substrate mixture based on
       Ser-Gln-Asn-Tyr-Pro-Ile-Val, where the P1' proline was substituted with
       20 naturally occurring amino acids. The hydrophobic residues Leu, Ile,
       Val, Phe, and Tyr were preferred in addition to Pro at the P1' site. The
       results were corroborated by performing the more laborious
       HPLC/Frit-fast atom bombardment/MS analyses.
 DE    Amino Acid Sequence  HIV Protease/*METABOLISM  Mass Fragmentography
       Molecular Sequence Data  Molecular Weight  Substrate Specificity
       Support, U.S. Gov't, P.H.S.  Time Factors  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).