We describe an adaptation of φC31 integrase-mediated targeted cassette exchange for use in Drosophila cell lines. Single copies of an attP-bounded docking platform carrying a GFP-expression marker, with or without insulator elements flanking the attP sites, were inserted by P-element transformation into the Kc167 and Sg4 cell lines; each of the resulting docking-site lines carries a single mapp...

We have previously described the development of oncoretrovirus vectors for human -globin using a truncated -globin promoter, modified -globin cassette, and -globin enhancer. However, one of these vectors is genetically unstable, and both vectors exhibit variable expression patterns in cultured cells, common characteristics of oncoretrovirus vectors for globin genes. To address these problems, w...

OBJECTIVES Integrons are considered expression systems due to the presence of Pc promoters that drive gene cassette transcription. The role and configurations of Pc are well known in class 1 integrons; however, this region has not yet been identified in class 2 integrons. This study aimed to characterize the Pc promoter from class 2 integrons and to determine the effect of gene cassette positio...

Bacterial resistance to β-lactams may rely on acquired β-lactamases encoded by class 1 integron-borne genes. Rearrangement of integron cassette arrays is mediated by the integrase IntI1. It has been previously established that integrase expression can be activated by the SOS response in vitro, leading to speculation that this is an important clinical mechanism of acquiring resistance. Here we r...

BACKGROUND Recombineering is a genetic engineering tool that enables facile modification of large episomal clones, e.g. BACs, fosmids. We have previously adapted this technology to generate, directly from fosmid-based genomic clones, fusion gene reporter constructs designed to investigate gene expression patterns in C. elegans. In our adaptation a rpsL-tet(A) positive/negative-selection cassett...

We have constructed two plasmid vectors for cloning and expression of DNA fragments controlled by the lac promoter as a NotI-expression cassette. Whereas plasmid pSJ33 allows mobilization of the expression cassette into a wide variety of Gram-negative bacteria by RP4-mediated conjugation, the low-copy-number plasmid pSJP18Not facilitates cloning and expression in Escherichia coli when high gene...

BACKGROUND The classic AOX1 replacement approach is still one of the most often used techniques for expression of recombinant proteins in the methylotrophic yeast Pichia pastoris. Although this approach is largely successful, it frequently delivers clones with unpredicted production characteristics and a work-intense screening process is required to find the strain with desired productivity. ...

background: infectious bursal disease virus (ibdv) causes a highly immunosuppressive disease in chickens and is a pathogen of major economic importance to the poultry industry worldwide. the vp2 protein is the major host-protective immunogen of ibdv and has been considered as a potential subunit vaccine against the disease. vp2 coding sequence was cloned in an inducible fungal vector and the pr...

conclusions: the recombinant baculovirus constructed in this work has proper characteristics to produce h5n1 influenza virus-like particles in sf9 cells. results: restriction map of pfastbacihnm1 plasmid confirmed the fidelity of the clone. the pcr carried out on the recombinant bacmids as template indicated that a proper homologous recombination has occurred between pfastbacihnm1 donor plasmid...