Isolation of a yeast single-strand deoxyribonucleic acid binding protein that specifically stimulates yeast DNA polymerase I
- 21 June 1983
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 22 (13), 3214-3219
- https://doi.org/10.1021/bi00282a027
Abstract
Work was conducted to find a protein from yeast that would bind more strongly to single-stranded DNA than to duplex DNA and would stimulate the activity of the major yeast DNA polymerase, but not polymerases from other organisms. A protein was isolated that binds about 200 times more strongly to single-stranded DNA than duplex DNA and stimulates yeast DNA polymerase I activity 4-5-fold. It inhibits synthesis catalyzed by calf thymus DNA polymerase .alpha. and has little effect on T4 DNA polymerase. This yeast protein, SSB-1, has a MW of .apprx. 40,000. At apparent saturation there is 1 protein molecule bound per 40 nucleotides. Protein binding causes the single-stranded DNA molecule to assume a relatively extended conformation. It binds to single-stranded RNA as strongly as to DNA. SSB-1 increases the initial rate of polymerization catalyzed by yeast DNA polymerase I apparently by increasing the processivity of the enzyme. There are 7500-30,000 molecules of SSB-1 per yeast cell, enough to bind at least 400-1600 nucleotides per replication fork. It is present in sufficient abundance to participate in DNA replication in vivo in the manner suggested by these in vitro experiments.This publication has 9 references indexed in Scilit:
- New temperature-sensitive mutants of Saccharomyces cerevisiae affecting DNA replicationMolecular Genetics and Genomics, 1982
- Studies on the mechanism of DNA polymerase alpha. Nascent chain elongation, steady state kinetics, and the initiation phase of DNA synthesis.Journal of Biological Chemistry, 1981
- Studies on the structure of mouse helix-destabilizing protein-1. DNA binding and controlled proteolysis with trypsin.Journal of Biological Chemistry, 1980
- An Escherichia coli mutant defective in single-strand binding protein is defective in DNA replication.Proceedings of the National Academy of Sciences, 1979
- On the processive mechanism of Escherichia coli DNA polymerase I. Quantitative assessment of processivity.Journal of Biological Chemistry, 1978
- DNA polymerases from bakers' yeast.Journal of Biological Chemistry, 1977
- A Single-Strand-Specific DNA-Binding Protein from Mouse Cells that Stimulates DNA Polymerase.. Its Modification by PhosphorylationEuropean Journal of Biochemistry, 1977
- ENZYMATIC SYNTHESIS OF DEOXYRIBONUCLEIC ACID .9. POLYMERASE FORMED AFTER T2 BACTERIOPHAGE INFECTION OF ESCHERICHIA COLI - NEW ENZYME1962
- PROTEIN MEASUREMENT WITH THE FOLIN PHENOL REAGENTJournal of Biological Chemistry, 1951