Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Significance of nucleobase shape complementarity and hydrogen bonding in the formation and stability of the closed polymerase-DNA complex
Autore:
Dzantiev, L; Alekseyev, YO; Morales, JC; Kool, ET; Romano, LJ;
Indirizzi:
Wayne State Univ, Dept Chem, Detroit, MI 48202 USA Wayne State Univ Detroit MI USA 48202 v, Dept Chem, Detroit, MI 48202 USA Stanford Univ, Dept Chem, Stanford, CA 94305 USA Stanford Univ Stanford CA USA 94305 iv, Dept Chem, Stanford, CA 94305 USA
Titolo Testata:
BIOCHEMISTRY
fascicolo: 10, volume: 40, anno: 2001,
pagine: 3215 - 3221
SICI:
0006-2960(20010313)40:10<3215:SONSCA>2.0.ZU;2-3
Fonte:
ISI
Lingua:
ENG
Soggetto:
I KLENOW FRAGMENT; N-2-AMINOFLUORENE ADDUCTS; REVERSE-TRANSCRIPTASE; CONFORMATIONAL CHANGE; ACTIVE-SITE; REPLICATION; FIDELITY; N-ACETYL-2-AMINOFLUORENE; DIFLUOROTOLUENE; MECHANISM;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
25
Recensione:
Indirizzi per estratti:
Indirizzo: Romano, LJ Wayne State Univ, Dept Chem, Detroit, MI 48202 USA Wayne State Univ Detroit MI USA 48202 m, Detroit, MI 48202 USA
Citazione:
L. Dzantiev et al., "Significance of nucleobase shape complementarity and hydrogen bonding in the formation and stability of the closed polymerase-DNA complex", BIOCHEM, 40(10), 2001, pp. 3215-3221

Abstract

DNA polymerases insert a dNTP by a multistep mechanism that involves a conformational rearrangement from an open to a closed ternary complex, a process that positions the incoming dNTP in the proper orientation for phosphodiester bond formation. In this work, the importance and relative contribution of hydrogen-bonding interactions and the geometric shape of the base pairthat forms during this process were studied using Escherichia coli DNA polymerase I(Klenow fragment, 3'-exonuclease deficient) and natural dNTPs or non-hydrogen-bonding dNTP analogues. Both the geometric fit of the incoming nucleotide and its ability to form Watson-Crick hydrogen bonds with the template were found to contribute to the stability of the closed ternary complex. Although the formation of a closed complex in the presence of a non-hydrogen-bonding nucleotide analogue could be detected by limited proteolysis analysis, a comparison of the stabilities of the ternary complexes indicated that hydrogen-bonding interactions between the incoming dNTP and the template increase the stability of the complex by 6-20-fold. Any deviation fromthe Watson-Crick base pair geometry was shown to have a destabilizing effect on the closed complex. This degree of destabilization varied from 3- to 730-fold and was found to be correlated with the size of the mismatched base pair. Finally, a stable closed complex is nor formed in the presence of addNTP or rNTP, These results are discussed in relation to the steric exclusion model for the nucleotide insertion.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 03/04/20 alle ore 11:03:38