THE ROLE OF CYSTEINE THEOLSIEN HUMAN IMMUNODEFICIENCY VIRUS INACTIVATION

Abstract

Human immunodeficiency virus type one (HIV-1) was treated with the sulthydryl reagents N-ethylmaleimide (NEM) and 4-vinylpyridine (4-VP). Their effects on replication and on viral proteins functioning in early replication steps were evaluated in cellular and biochemical assays. NEM rapidly inactivated HIV-1, but 4-VP had only a modest effect. Adding a membrane-permeable chelator improved the effectiveness of 4-VP, but it was still less effective than NEM. Reverse transcriptase remained functional in NEM- and 4- VP-treated virus, but DNA intermediate products were absent from NEM-treated virus. With 4-VP, DNA intermediates were synthesized, but proviral integration was greatly reduced. NEM reacted extensively with nucleocapsid protein (NC), a zinc-binding protein important for early replication steps. In contrast, 4-VP was unable to react with NC unless zinc was removed by a chelator. Chemically inactivating HIV-1 by derivatizing cysteine thiols depended on reaction with zinc-bound domains, notably the zinc fingers of NC.