Detail of "9050-76-4"

Reference

Initiation of DNA replication in Escherichia coli: RNase H-deficient mutants do not require the dnaA function

Initiation of DNA replication in Escherichia coli: RNase H-deficient mutants do not require the dnaA function. Lindahl, Gunnar; Lindahl, Tomas (Dep. Med. Microbiol., Univ. Lund, Lund S-223 62, Swed.). MGG, Mol. Gen. Genet., 196(2), 283-9 (English) 1984. CODEN: MGGEAE. ISSN: 0026-8925. DOCUMENT TYPE: Journal CA Section: 3 (Biochemical Genetics) Section cross-reference(s): 10 A series of temp.-resistant revertants were isolated from strains of E. coli K12 carrying a temp.-sensitive (ts) mutation in the dnaA gene. Four independent revertants were found which still carry the original ts mutation. The ability of these strains to grow at high temp. is due to a suppressor mutation, called sin. All four sin mutations are located between the genes metD and proA on the genetic map of E. coli, which suggests that they all affect the same gene. The sin suppressors, which were isolated for their ability to suppress 1 dnaA mutation, are also able to suppress 3 other temp.-sensitive dnaA mutations, but they are not able to suppress mutations in either of the 2 genes dnaB or dnaC. The sin suppressors alone do not confer any particular phenotype on bacteria, but they are deficient in the enzyme RNase H [9050-76-4]. It is proposed that the function of the dnaA protein is to protect a DNA-RNA hybrid at the origin of replication against RNase H.

Replication initiated at the origin (oriC) of the E

Replication initiated at the origin (oriC) of the E. coli chromosome reconstituted with purified enzymes. Kaguni, Jon M.; Kornberg, Arthur (Sch. Med., Stanford Univ., Stanford, CA 94305, USA). Cell (Cambridge, Mass.), 38(1), 183-90 (English) 1984. CODEN: CELLB5. ISSN: 0092-8674. DOCUMENT TYPE: Journal CA Section: 3 (Biochemical Genetics) Section cross-reference(s): 6, 7 A crude sol. enzyme system capable of authentic replication of a variety of oriC plasmids was replaced by purified proteins constituting 3 functional classes: initiation proteins (RNA polymerase [9014-24-8], dnaA protein, gyrase) that recognize the oriC sequence and presumably prime the leading strand of the replication fork, replication proteins (DNA polymerase III [37217-33-7] holoenzyme, single-strand-binding protein, primosomal proteins) that sustain progress of the replication fork, and specificity proteins (topoisomerase I [80449-01-0], RNase H [9050-76-4], protein HU) that suppress initiation of replication at sequences, other than oriC, coated with dnaA protein. Protein HU and unidentified factors in crude enzyme fractions stimulate replication at 31 stages. Replication has been sepd. temporally and phys. into successive stages of RNA synthesis and DNA synthesis.