Inhibition of human immunodeficiency virus type 1 reverse transcriptase, protease and integrase by bovine milk proteins

Different proteins have been isolated from bovine milk including lactoferri n, lactoperoxidase, glycolactin, angiogenin-1, lactogenin, alpha -lactalbum in, lactoglobulin and casein. These proteins have been assayed for inhibito ry activity against human immunodeficiency virus type I (HIV-1) reverse tra nscriptase, protease and integrase, enzymes crucial to the HIV-1 life cycle . It was found that different milk proteins inhibited the three aforementio ned HIV enzymes to different extents. Lactoferrin strongly inhibited HIV-1 reverse transcriptase but only slightly inhibited HIV-1 protease and integr ase. On the other hand, alpha -lactalbumin, beta -lactoglobulin and casein inhibited HIV-I protease and integrase to an appreciable extent but did not inhibit HIV-I reverse transcriptase. Glycolactin and angiogenin-1 suppress ed the activity of HIV-I reverse transcriptase by a moderate extent but mor e powerfully inhibited HIV-I protease and integrase. In comparison with the other milk proteins glycolactin was a strong inhibitor of HIV-I protease a nd integrase and a moderate inhibitor of HIV-I reverse transcriptase. Lacto genin was a strong inhibitor of HIV-I integrase, a moderate inhibitor of HI V-I reverse transcriptase and a weak inhibitor of HIV-I protease. (C) 2001 Elsevier Science Inc. All rights reserved.