Inhibition of HIV-1 reverse transcriptase and protease by phlorotannins from the brown alga Ecklonia cava

Biol Pharm Bull. 2004 Apr;27(4):544-7. doi: 10.1248/bpb.27.544.

Abstract

The bioassay-directed isolation of a marine brown alga, Ecklonia cava, afforded four phlorotannin derivatives, eckol (1), 8,8'-bieckol (2), 8,4"'-dieckol (3), and phlorofucofuroeckol A (4). Among these compounds, 2 and 3 exhibited an inhibitory effect on human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) and protease. Specifically, they inhibited the RT more potently than the protease. The inhibitory activity of compound 2 (IC(50), 0.51 microM) against HIV-1 RT was comparable to that of nevirapine (IC(50), 0.28 microM), a reference compound. An enzyme kinetic assay showed that this compound inhibited the RNA-dependent DNA synthesis activity of HIV-1 RT noncompetitively against dUTP/dTTP with a K(i) value of 0.78 microM. With respect to the homopolymeric template/primer, (rA)n(dT)15, 8,8'-bieckol (2) displayed an uncompetitive type of inhibition (K(i), 0.23 microM).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • HIV Protease / chemistry*
  • HIV Reverse Transcriptase / antagonists & inhibitors*
  • HIV Reverse Transcriptase / chemistry
  • Phaeophyceae / chemistry*
  • Protease Inhibitors / chemistry*
  • RNA-Directed DNA Polymerase / isolation & purification
  • Reverse Transcriptase Inhibitors / chemistry*
  • Tannins / chemistry*
  • Tannins / isolation & purification

Substances

  • Protease Inhibitors
  • Reverse Transcriptase Inhibitors
  • Tannins
  • HIV Reverse Transcriptase
  • RNA-Directed DNA Polymerase
  • HIV Protease