A self-regulated high-copy number plasmid containing chloramphenicol resistant gene, for the production of recombinant proteins under the regulation of bacteriophage λpL promoter, was constructed. The designed 5024 base pair expression plasmid contained a heat sensitive repressor cI857 coding gene to regulate the function of λpL promoter under heat shock induction. Using the constructed vector,...

Ferroxidase (encoded by the mco gene), a component of a ferrous iron uptake pathway in Pseudomonas aeruginosa, was detected in all of the 35 respiratory clinical isolates surveyed; in contrast, considerable variation in siderophore expression was observed. The ubiquitous expression of this periplasmic ferroxidase suggests that it plays a key role in iron uptake in this opportunistic pathogen.

Streptokinase (SK) is an extracellular protein comprising 414 amino acids with considerable clinical importance as a commonly used thrombolytic agent. Due to its wide spread application and clinical importance designing more efficient SK production platforms worth investigatinginvestigation. In this regard, a synthetic SK gene was optimized and cloned in to pET21b plasmid for periplasmic expres...

BACKGROUND In current protein research, a limitation still is the production of active recombinant proteins or native protein associations to assess their function. Especially the localization and analysis of protein-complexes or the identification of modifications and small molecule interaction partners by co-purification experiments requires a controllable expression of affinity- and/or fluor...

A total of 103 strains of Aeromonas spp. isolated from clinical and from environmental samples was compared by using SDS-PAGE of periplasmic proteins patterns. Strains isolated from Polish children suffering from gastroenteritis did not appear similar to strains isolated from human living in Hong-Kong. Aeromonas sp. strains did not show a tendency to cluster according to their origin. Our resul...

A specific expression system for Thermus spp. is described. Plasmid pMKE1 contains replicative origins for Escherichia coli and Thermus spp., a selection gene encoding a thermostable resistance to kanamycin, and a 720 bp DNA region containing the promoter (Pnar), and the regulatory sequences of the respiratory nitrate reductase operon of Thermus thermophilus HB8. Two genes, encoding a thermophi...

In this study, we investigate the expression of Brucella abortus proteins in resporise to oxidative stress. The focus is on several proteins thought to be involved in bacterial protection. We show that catalase and Cu-Zn superoxide dismutase are regulated in response to H2O2 or by superoxide, whereas expression of Hsp70 and Hsp60 are not dramatically affected by oxidative stress. The regulation...

For more than 20 years now, periplasmic expression in Escherichia coli has become the standard technology for preparing functional antibody fragments in a rapid and convenient way (Skerra and Plückthun 1988; Plückthun et al. 1996). The criteria of choosing either the Fab or single-chain Fv fragment (scFv) format, the properties of suitable expression vectors, as well as the influence of the E. ...