DNA synthesis primed by mononucleotides (de novo synthesis) catalyzed by HIV‐1 reverse transcriptase: tRNALys,3 activation

FEBS Letters

Litvak, Simon¹  Tarrago-Litvak, Laura¹  Nevinsky, Georgyi A.²  Fournier, Michel¹  Zakharova, Ol'ga D.² 

[1] Institut de Biochemie et Génétique Cellulaires du CNRS 1, rue Camille Saint-Saëns, 33077 Bordeaux cedex, France;Institute of Bioorganic Chemistry, Siberian Division of the Academy of Sciences of Russia, Novosibirsk 630090, Russian Federation

关键词: HIV-1;    Reverse transcriptase;    tRNALys;    3 induced activation;    Synthesis (de novo);    RT;    reverse transcriptase;    HIV-1;    human immunodeficiency virus type 1;    DMSO;    dimethyl sulfoxide;   

DOI  :  10.1016/0014-5793(95)01056-K

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

HIV-1 RT is able to catalyze DNA synthesis starting from mononucleotides used both as minimal primers and as nucleotide substrates (de novo synthesis) in the presence of a complementary template. The rate of this process is rather slow when compared to the polymerization primed by an oligonucleotide. The addition of tRNA^Lys,3 to this system increased the de novo synthesis rate by 2-fold. Addition of low concentrations of agents able to modify protein conformation, such as urea, dimethylsulfoxide and Triton X-100, can activate the de novo synthesis by a factor 2 to 5. A dramatic synergy is observed in the presence of the three compounds since the stimulating effect of tRNA increases 10–15 times. These results suggest that compounds activating RT are able to induce a conformational change of the enzyme which results in a higher specific activity. Primer tRNA seems to play an important role in HIV-1 RT modification(s) leading to a polymerase having a higher affinity for the primer or the dTTP, but not for the template. The specificity of RT for the template is not influenced by changes in the kinetics or in the thermodynamic parameters of the polymerization reaction.

【 授权许可】

Unknown