Document 0107
 DOCN  M9470107
 TI    Subunit-selective mutagenesis of Glu-89 residue in human
       immunodeficiency virus reverse transcriptase. Contribution of p66 and
       p51 subunits to nucleoside analog sensitivity, divalent cation
       preference, and steady state kinetic properties.
 DT    9409
 AU    Kew Y; Qingbin S; Prasad VR; Department of Microbiology and Immunology,
       Albert Einstein; College of Medicine, New York, New York 10461.
 SO    J Biol Chem. 1994 May 27;269(21):15331-6. Unique Identifier : AIDSLINE
       MED/94253100
 AB    The E89G alteration in the human immunodeficiency virus type 1 reverse
       transcriptase has been shown to confer resistance to nucleoside analogs
       and a loss of magnesium cation preference (Prasad, V.R., Lowy, I., De
       Los Santos, T., Chiang, L., and Goff, S.P. (1991) Proc. Natl. Acad. Sci.
       U.S.A. 88, 11363-11367. The wild type reverse transcriptase heterodimer,
       chimeric reverse transcriptases that contain the E89G alteration in one
       of the subunits (p66wt/p51m and p66m/p51wt), and the mutant enzyme
       (p66m/p51m) were prepared. Analysis of steady state kinetic parameters
       showed that the mutant enzyme (p66m/p51m) displayed a higher Vmax, a
       higher Km for 2'-deoxythymidine triphosphate, and a higher Ki for
       2',3'-dideoxythymidine triphosphate than the wild type enzyme. The
       increased Km and Ki values were observed only when a heterodimer
       contained the alteration in the p66 subunit. Tests for divalent cation
       requirement showed that only the dimers containing the wild type p66
       (p66wt/p51wt and p66wt/p51m) displayed a preference for magnesium. Our
       results indicate that p66 plays a dominant role in deoxynucleotide
       triphosphate substrate recognition (Km), nucleoside analog sensitivity
       (Ki), and magnesium preference. However, the increased Vmax displayed by
       the mutant enzyme (p66m/p51m) appeared to be determined by both of the
       subunits.
 DE    Base Sequence  Cations, Divalent/METABOLISM  DNA Primers
       Foscarnet/PHARMACOLOGY  Glutamates/*GENETICS  Human  HIV-1/DRUG
       EFFECTS/*ENZYMOLOGY/GENETICS  Kinetics  Molecular Sequence Data
       *Mutagenesis, Site-Directed  Reverse Transcriptase/ANTAGONISTS &
       INHIB/CHEMISTRY/*GENETICS  Support, Non-U.S. Gov't  Support, U.S. Gov't,
       P.H.S.  Thymine Nucleotides/PHARMACOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).