       Document 0608
 DOCN  M9550608
 TI    Backbone dynamics of Escherichia coli ribonuclease HI: correlations with
       structure and function in an active enzyme.
 DT    9505
 AU    Mandel AM; Akke M; Palmer AG 3rd; Department of Biochemistry and
       Molecular Biophysics, Columbia; University, New York, NY 10032.
 SO    J Mol Biol. 1995 Feb 10;246(1):144-63. Unique Identifier : AIDSLINE
       MED/95156479
 AB    Ribonuclease H is an endonuclease that hydrolyzes the RNA moiety of
       RNA-DNA duplex molecules. Escherichia coli ribonuclease H is involved in
       DNA replication, and retroviral ribonuclease H is essential for reverse
       transcription of the viral genome. To characterize the intramolecular
       dynamical properties of E. coli ribonuclease H, spin-lattice relaxation
       rate constants, spin-spin relaxation rate constants and steady state
       nuclear Overhauser effects for the 15N nuclear spins were measured by
       using proton-detected heteronuclear NMR spectroscopy. The relaxation
       data were analyzed by using a series of dynamical models in conjunction
       with a statistical model selection protocol. Ribonuclease H exhibits a
       complex array of dynamical features, most notably in the parallel
       beta-strands of the principal five-stranded beta-sheet, the coiled-coil
       helical interface, the active site, and the loop regions surrounding the
       active site. The dynamical properties are correlated with local
       structural environments of the 15N spins and suggest possible
       relationships to the functional properties of ribonuclease H. Results
       for E. coli ribonuclease H are compared to previously reported results
       for the human immunodeficiency virus type 1 ribonuclease H domain of
       reverse transcriptase.
 DE    Binding Sites  Escherichia coli/*ENZYMOLOGY  Human  HIV-1/ENZYMOLOGY
       *Models, Molecular  Molecular Structure  Nuclear Magnetic Resonance
       *Protein Structure, Secondary  Reverse Transcriptase/CHEMISTRY
       Ribonuclease H, Calf Thymus/*CHEMISTRY/METABOLISM  Structure-Activity
       Relationship  Support, Non-U.S. Gov't  Support, U.S. Gov't, P.H.S.
       JOURNAL ARTICLE

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

