The lagging strand of the replication fork is initially copied as short Okazaki fragments produced by the coupled activities of two template-dependent enzymes, a primase that synthesizes RNA primers and a DNA polymerase that elongates them. Gene 4 of bacteriophage T7 encodes a bifunctional primase-helicase that assembles into a ring-shaped hexamer with both DNA unwinding and primer synthesis ac...

A novel Pichia pastoris expression vector (pEZT7) for the production of recombinant proteins employing prokaryotic bacteriophage T7 RNA polymerase (T7 RNAP) (EC 2.7.7.6) and the corresponding promoter pT7 was constructed. The gene for T7 RNAP was stably introduced into the P. pastoris chromosome 2 under control of the (endogenous) constitutive P. pastoris glyceraldehyde-3-phosphate dehydrogenas...

Abstract In this study, we constructed recombinant luminescent Escherichia coli with T7, T3, and SP6 promoters inserted between tol lux genes as toluene biosensors evaluated their sensitivity, selectivity, specificity for measuring bioavailable in groundwater river water. The luminescence intensity of each biosensor depended on temperature, incubation time, ionic strength, concentrations coexis...

We have discovered that T7 RNA polymerase, purified to apparent homogeneity from overexpressing Escherichia coli cells, possesses a DNase and an RNase activity. Mutations in the active center of T7 RNA polymerase abolished or greatly decreased the nuclease activity. This nuclease activity is specific for single-stranded DNA and RNA oligonucleotides and does not manifest on double-stranded DNAs....

The gene encoding bacteriophage T7 RNA polymerase (T7gene1) was placed under the control of regulatory elements from the Escherichia coli lac operon to construct an inducible vaccinia virus expression system consisting entirely of prokaryotic transcriptional machinery. Regulated expression of T7 RNA polymerase was necessary to construct a stable recombinant vaccinia virus harboring a T7 promote...

Background and Aims: Q59L mutant of L-asparaginase enzyme from Escherichia coli (E. coli) has been introduced with lower side effects. This version of the enzyme might have potential applications in the treatment of leukemia patients. We utilized SHuffle T7 strain of E. coli, to produce the mutant enzyme in the presence of chaperone molecules. Materials and Methods: Q59LAsp gene was cloned in...

BACKGROUND Amino acid sequence diversity is introduced into a phage-displayed peptide library by randomizing library oligonucleotide DNA. We recently evaluated the diversity of peptide libraries displayed on T7 lytic phage and M13 filamentous phage and showed that T7 phage can display a more diverse amino acid sequence repertoire due to differing processes of viral morphogenesis. METHODS In t...

Single-stranded DNA-binding protein (gp2.5), encoded by gene 2.5 of bacteriophage T7, plays an essential role in DNA replication. Not only does it remove impediments of secondary structure in the DNA, it also modulates the activities of the other replication proteins. The acidic C-terminal tail of gp2.5, bearing a C-terminal phenylalanine, physically and functionally interacts with the helicase...