N-terminal HIV-1 Tat nonapeptides as inhibitors of dipeptidyl peptidase IV. Conformational characterization.
Compared to the N-terminal nonapeptide of the HIV-1 Tat protein as inhibitor of activity of DP IV which is supposed to mediate the immunosuppressive effects of HIV-1 Tat, the Ile5 and Leu6 analogues showed strongly reduced inhibitory activity. Interestingly, replacement of Asp2 with Gly or Lys led to compounds with considerably enhanced inhibition. Therefore, we have applied 1H NMR spectroscopy and restrained molecular dynamics calculations to elucidate the molecular conformation of a series of Tat nonapeptides. Conformational backbone differences of these peptides as well as the nature and the arrangement of the side chains per se at significant positions preventing effective binding to DP IV might explain their different inhibitory activity on DP IV.
Mrestani-Klaus
C
C
Department of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Germany.
Fengler
A
A
Faust
J
J
Brandt
W
W
Wrenger
S
S
Reinhold
D
D
Ansorge
S
S
Neubert
K
K
D019943:Amino Acid Substitution; D000818:Animals; D018819:Dipeptidyl Peptidase 4 / Q000737:chemistry / Q000187:drug effects*; D015696:Gene Products, tat / Q000737:chemistry / Q000494:pharmacology*; D015497:HIV-1 / Q000737:chemistry*; D006801:Humans; D007107:Immune System / Q000201:enzymology; D009682:Magnetic Resonance Spectroscopy; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D011487:Protein Conformation; D015842:Serine Proteinase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D013552:Swine; D054322:tat Gene Products, Human Immunodeficiency Virus
D015696:Gene Products, tat; D010446:Peptide Fragments; D015842:Serine Proteinase Inhibitors; D054322:tat Gene Products, Human Immunodeficiency Virus; D018819:Dipeptidyl Peptidase 4