As. Werneck et al., THE HYPERMODIFIED Y-BASE ELECTROSTATIC CONTRIBUTION TO THE ENERGETICSOF THE CODON-ANTICODON PAIRING IN TRNA(PHE), Journal of molecular structure. Theochem, 427, 1998, pp. 15-23
We report ab initio results at the Hartree-Fock/6-31G level for the en
ergetics of the codon-anticodon pairing in tRNA(Phe). We have employed
a molecular dynamics protocol in order to relax the studied crystallo
graphic structure. Electrostatic potentials due to the presence of the
hypermodified Y base and a guanine base in position 37 of the anticod
on loop are compared. The results of the electrostatic potentials on t
he planes containing the molecules of the complementary codon bases UU
C, indicate a strong energetic stabilization when a Y base is present,
in comparison to the substitution by a guanine base. The present resu
lts provide some molecular data on the energetics of the codon-anticod
on pairing mechanism and are related to experimental studies which sug
gest that hypermodification in tRNAs contribute to the regulation of g
ene expression. (C) 1998 Elsevier Science B.V.