title: Spatial relationship between polymerase and exonuclease active sites of phage T4 DNA polymerase enzyme.
abstract: The spatial relationship between the polymerase and exonuclease active sites of bacteriophage T4 DNA polymerase enzyme has been examined using a bulky biotin-streptavidin block at a specified position in an oligonucleotide (Fig. 1). The idea was to monitor the closest distance of approach of the T4 enzyme before being blocked by the bulky biotin-streptavidin complex while performing either of its activities. The results indicated a distance of 4-5 nucleotides between the biotin-streptavidin probe and the exonuclease site and a distance requirement of at least 7 nucleotides between the bulky probe and the 3'-primer terminus for efficient polymerization by the T4 enzyme. The difference in the two distances suggested a separation of 2-3 nucleotides between the two active sites of the T4 enzyme.
authors.affiliation: Department of Chemistry, Pennsylvania State University, University Park 16802-6300.
authors.forename: V
authors.initials: V
authors.lastname: Gopalakrishnan
authors.forename: S J
authors.initials: SJ
authors.lastname: Benkovic
mesh_terms: D001426:Bacterial Proteins; D001483:Base Sequence; D001665:Binding Sites; D001710:Biotin; D017931:DNA Primers; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000378:metabolism*; D005090:Exodeoxyribonucleases / Q000378:metabolism*; D008969:Molecular Sequence Data; D019809:Streptavidin; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D014764:Viral Proteins; C069983:gene 43 protein, Enterobacteria phage T4; D001710:Biotin; D019809:Streptavidin; D004259:DNA-Directed DNA Polymerase; D005090:Exodeoxyribonucleases