Processing of A-form ssDNA by cryptic RNase H fold exonuclease PF2046.
Arch Biochem Biophys
; 606: 143-50, 2016 09 15.
Article
em En
| MEDLINE
| ID: mdl-27495739
ABSTRACT
RNase H fold protein PF2046 of Pyrococcus furiosus is a 3'-5' ssDNA exonuclease that cleaves after the second nucleotide from the 3' end of ssDNA and prefers poly-dT over poly-dA as a substrate. In our crystal structure of PF2046 complexed with an oligonucleotide of four thymidine nucleotides (dT4), PF2046 accommodates dT4 tightly in a groove and imposes steric hindrance on dT4 mainly by Phe220 such that dT4 assumes the A-form. As poly-dA prefer B-form due to the stereochemical restrictions, the A-form ssDNA binding by PF2046 should disfavor the processing of poly-dA. Phe220 variants display reduced activity toward poly-dA and the A-form appears to be a prerequisite for the processing by PF2046.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
DNA de Cadeia Simples
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Ribonuclease H
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Pyrococcus furiosus
Idioma:
En
Revista:
Arch Biochem Biophys
Ano de publicação:
2016
Tipo de documento:
Article