Dual role of φ29 DNA polymerase Lys529 in stabilisation of the DNA priming-terminus and the terminal protein-priming residue at the polymerisation site.

ABSTRACT: Resolution of the crystallographic structure of φ29 DNA polymerase binary and ternary complexes showed that residue Lys529, located at the C-terminus of the palm subdomain, establishes contacts with the 3' terminal phosphodiester bond. In this paper, site-directed mutants at this Lys residue were used to analyse its functional importance for the synthetic activities of φ29 DNA polymerase, an enzyme that starts linear φ29 DNA replication using a terminal protein (TP) as primer. Our results show that single replacement of φ29 DNA polymerase residue Lys529 by Ala or Glu decreases the stabilisation of the primer-terminus at the polymerisation active site, impairing both the insertion of the incoming nucleotide when DNA and TP are used as primers and the translocation step required for the next

SUBMITTER: del Prado A 

PROVIDER: S-EPMC3762793 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature