The aim of the present study was to construct a fast-acting, eukaryotic expression vector in eukaryotic cells based on transmembrane-tumor necrosis factor‑α (TM‑TNF‑α) structure. Two types of recombinant eukaryotic expression vectors were constructed, pcDNA3.1-TM-enterokinase-TNF‑α and pcDNA3.1‑TM‑Factor Xa‑TNF‑α, according to the TNF‑α transmembrane segments. Following the generation of these ...

In order to circumvent the difficulty encountered in the expression and purification of the recombinant products in E. coli system, we have developed a novel and facile method of removing the polyhistidine tag from target proteins after heterologous gene expression. The expression of a serine protease (Tm-5) from Taiwan habu (Trimeresurus mucrosquamatus) is taken as an exemplar to illustrate th...

A solution of crystalline trypsinogen in dilute buffer containing a trace of active trypsin when allowed to stand at pH 5.0-9.0 and 5 degrees C. is gradually transformed partly into trypsin protein and partly into an inert protein which can no longer be changed into trypsin either by enterokinase or mold kinase. During the process of formation of trypsin and inert protein the ratio of the conce...

An affinity tag consisting of six adjacent histidine residues followed by an enterokinase cleavage site was genetically engineered at the N-terminus of the glutamate transport protein GltT of the thermophilic bacterium Bacillus stearothermophilus. The fusion protein was expressed in Escherichia coli and shown to transport glutamate. The highest levels of expression were observed in E. coli stra...

In the area of protein production and purification, researchers have turned to eukaryotic organisms, such as Schizosaccharomyces pombe, as hosts for expression of many eukaryotic proteins instead of bacterial organisms. The reasons are many: some bacterial hosts cannot manage eukaryotic genes due to their toxicity, insolubility or their need for posttranslational modifications, such as phosphor...

BACKGROUND Measurement of human kallikrein 2 (hK2) has improved early detection and staging of prostate cancer. However, reported concentrations of hK2 among currently used assays have not been standardized in any way. We compared two hK2 assays and five different recombinant hK2 variants (rhK2) and suggest a common calibrator as an important step and putative reference substance in hK2 assay s...

Iron is an essential nutrient for the survival and pathogenesis of bacteria, but relatively little is known regarding its transport and regulation in staphylococci. Based on the known sequences of ferric-uptake regulatory (fur) genes from several Gram-positive and Gram-negative bacteria, a fragment containing the fur homologue was cloned from a genomic library of Staphylococcus aureus RN450. Nu...