T7 gene 6 exonuclease has been shown to have an RNase H activity as well as a double-strand specific DNase activity by the following experiments: The RNase H activity coelutes with the DNase activity from DEAE-cellulose, phosphocellulose, hydroxyapatite, and Sephadex G-200 columns. Gene 6 exonuclease specified by a T7 strain with a temperature sensitive mutation in gene 6 has an extremely heat-...

Four bacteriophages (A16, CK235, phi 1.2 and K31) which specifically attack different encapsulated strains of Escherichia coli have been shown to be related to bacteriophage T7 (which is unable to grow on encapsulated hosts). The conclusion that phages A16 and CK235 are related to T7 is based on similarities in the pattern of expression of intracellular phage proteins, early appearance, in infe...

Glioma-targeted drug delivery is a hugely challenging task because of the multibarrier in brain. In this study, we report magnetic T7 peptide&AS1411 aptamer-modified microemulsion for triple glioma-targeted shikonin and docetaxel (Fe3O4@T7/AS1411/DTX&SKN-M). Such system comprises two tumor-targeted ligands (T7 peptide AS1411 aptamer), ultra-small superparamagnetic iron oxide nanoparticle (Fe3O4...

Half of the 55 potential genes of bacteriophage T7 appear to be dispensable. One of the major obstacles in the study of these nonessential genes is the difficulty in obtaining mutants. During a study of genes involved in the packaging of bacteriophage T7, we hypothesized that some nonessential genes may be required for optimal growth. Mutant phages lacking such nonessential genes may form plaqu...

An in vitro system that supports the efficient growth of hepatitis C virus (HCV) and reflects its complete in vitro replication cycle has not yet been established. The establishment of a minigene RNA of HCV in mammalian cells could facilitate the study of virus-cell interactions and the molecular pathogenesis of this virus. We constructed a replication-deficient recombinant adenovirus expressin...

Vaccination, one of the most effective and cost-efficient strategy in preventing and controlling influenza virus infection, also has poorly immunogenicity and side effects. Thus, adjuvants are employed to augment the immune response and overcome the drawbacks of vaccine. Here, we present a novel Toll-like receptor agonist (SZU101, T7) to evaluate the adjuvanticity for inactivated H1N1 influenza...

The T7 RNA polymerase-T7 lysozyme complex regulates phage gene expression during infection of Escherichia coli. The 2.8 A crystal structure of the complex reveals that lysozyme binds at a site remote from the polymerase active site, suggesting an indirect mechanism of inhibition. Comparison of the T7 RNA polymerase structure with that of the homologous pol I family of DNA polymerases reveals id...

Although highly specialized, T7 RNA polymerase seems to possess a large range of DNA- and RNA-dependent properties. To study such flexibility, we determined the ability of T7 RNA polymerase to transcribe chimeric DNA-RNA and RNA templates following initiation at a double stranded DNA promoter. We have found that T7 RNA polymerase is able to initiate on RNA templates, was processive, and was abl...

BACKGROUND The most widespread, efficient prokaryotic protein-producing system is one where the T7 phage polymerase recognizes the T7 phage promoter (T7 p/p system). Unfortunately, in this system, target protein expression gradually declines and is often undetectable following 3 to 5 subcultures. Although a number of studies have attempted to stabilize the expression levels of the T7 p/p system...