The construction of synthetic gene circuits relies on our ability to engineer regulatory architectures that are orthogonal to the host's native regulatory pathways. However, as synthetic gene circuits become larger and more complicated, we are limited by the small number of parts, especially transcription factors, that work well in the context of the circuit. The current repertoire of transcrip...

Bacteriophage T7 DNA primase (gene-4 protein, 66,000 daltons) enables T7 DNA polymerase to initiate the synthesis of DNA chains on single-stranded templates. An initial step in the process of chain initiation is the formation of an oligoribonucleotide primer by T7 primase. The enzyme, in the presence of natural SS DNA, Mg++ (or Mn++), ATP and CTP (or a mixture of all 4 rNTPs), catalyzes the syn...

background: escherichia coli (e. coli) is the most extensively used host for the production of recombinant proteins. however, most of the eukaryotic proteins are typically obtained as insoluble, misfolded inclusion bodies that need solubilization and refolding. reteplase as a highly disulfide-bonded recombinant protein is an example of difficult to express protein in e. coli. methods: in this s...

We have found that the burst size of bacteriophage T7 was decreased in two Escherichia coli temperature-sensitive gyrase mutants incubated at the restrictive temperature. This reduction in burst size indicates that gyrase may be required for T7 growth.

Streptomyces lividans is a Gram-positive bacterium known for its remarkable secretion efficiency and low extracellular protease activity. In the present work, we adapted the highly productive T7 expression system to S. lividans. A codon-optimized T7 RNA polymerase gene was chromosomally integrated, and a bifunctional T7 expression vector was constructed.

BACKGROUND To optimize the production of membrane and secretory proteins in Escherichia coli, it is critical to harmonize the expression rates of the genes encoding these proteins with the capacity of their biogenesis machineries. Therefore, we engineered the Lemo21(DE3) strain, which is derived from the T7 RNA polymerase-based BL21(DE3) protein production strain. In Lemo21(DE3), the T7 RNA pol...

Gene 5 protein of bacteriophage T7 is a nonprocessive DNA polymerase. During infection of Escherichia coli, T7 annexes the host protein thioredoxin for use as a processivity factor for T7 DNA polymerase. We describe here a genetic method to investigate the interaction between T7 gene 5 protein and E. coli thioredoxin. The strategy is to use thioredoxin mutants that are unable to support the gro...

The capsid protein of feline calicivirus (FCV) was expressed by using plasmids containing cytomegalovirus, simian virus 40, or T7 promoters. The strongest expression was achieved with the T7 promoter and coinfection with vaccinia virus expressing the T7 RNA polymerase (MVA/T7pol). The FCV precursor capsid protein was processed to the mature-size protein, and these proteins were assembled in to ...