Binding mechanism of metal⋅NTP substrates and stringent-response alarmones to bacterial DnaG-type primases.

ABSTRACT: Primases are DNA-dependent RNA polymerases found in all cellular organisms. In bacteria, primer synthesis is carried out by DnaG, an essential enzyme that serves as a key component of DNA replication initiation, progression, and restart. How DnaG associates with nucleotide substrates and how certain naturally prevalent nucleotide analogs impair DnaG function are unknown. We have examined one of the earliest stages in primer synthesis and its control by solving crystal structures of the S. aureus DnaG catalytic core bound to metal ion cofactors and either individual nucleoside triphosphates or the nucleotidyl alarmones, pppGpp and ppGpp. These structures, together with both biochemical analyses and comparative studies of enzymes that use the same catalytic fold as DnaG, pinpoint the predomi

SUBMITTER: Rymer RU 

PROVIDER: S-EPMC3438381 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature