A novel tightly regulated gene expression system was developed for Escherichia coli by applying the regulatory elements of the Pseudomonas putida F1 cym and cmt operons to control target gene expression at the transcriptional level by using p-isopropylbenzoate (cumate) as an inducer. This novel expression system, referred to as the cumate gene switch, includes a specific expression vector, pNEW...

A forward mutagenesis system based on the acquisition of mutations that inactivate the thymidylate synthase gene (TMS) and confer a trimethoprim resistant (Tmpr) phenotype was developed and utilized to study transcription-mediated mutagenesis (TMM). In addition to thyA, Bacillus subtilis possesses thyB, whose expression occurs under conditions of cell stress; therefore, we generated a thyB- thy...

In Alzheimer Disease (AD), dementia is due to cell loss and impaired synaptic function. The cell loss is mediated by increased apoptosis, predisposition to apoptosis, and impaired mitochondrial function. Previous studies demonstrated that the AD7c-NTP neuronal thread protein gene is over-expressed in AD beginning early in the course of disease, and that in AD, AD7c-NTP protein accumulation in n...

The vaccinia virus WR A5L open reading frame (corresponding to open reading frame A4L in vaccinia virus Copenhagen) encodes an immunodominant late protein found in the core of the vaccinia virion. To investigate the role of this protein in vaccinia virus replication, we have constructed a recombinant virus, vA5Li, in which the endogenous gene has been deleted and an inducible copy of the A5 gen...

Cyanobacteria are oxygenic photosynthetic prokaryotes that are able to assimilate CO2 using solar energy and water. Metabolic engineering of cyanobacteria has suggested the possibility of direct CO2 conversion to value-added chemicals. However, engineering of cyanobacteria has been limited due to the lack of various genetic tools for expression and control of multiple genes to reconstruct metab...

PURPOSE Recently discovered Anabaena variabilis phenylalanine ammonia lyase (AvPAL) proved to be a good candidate for enzyme replacement therapy of phenylketonuria. Outstanding stability properties of a mutant version of this enzyme, produced already in our laboratory, have led us to the idea of culture conditions optimization for soluble expression of this therapeutically valuable enzyme in E....

BACKGROUND Hyaluronidase catalyzes the hydrolysis of hyaluronan polymers to N-acetyl-D-glucosamine and D-glucuronic acid. This enzyme is a dimer of identical subunits. Hyaluronidase has different pharmaceutical and medical applications. Previously, we produced a recombinant hyaluronidase antigenic fragment of Streptococcus pyogenes. OBJECTIVES This study aimed to improve the protein productio...

Three clock proteins--KaiA, KaiB, and KaiC--have been identified as essential components of the circadian oscillator in cyanobacteria, and Kai-based chemical oscillation is thought to be the basic circadian timing mechanism in Synechococcus elongatus PCC 7942. Transcription and translation of kaiBC in cyanobacterial cells was quantitatively studied to elucidate how these processes are coupled t...

To target tumor necrosis factor alpha (TNF-a) to tumor cells, recombinant DNA techniques were used to construct and express the fused gene VKLVH–TNF-a, which encodes the secreted form of single-chain fusion protein sFV/TNF-a in Escherichia coli. sFV/TNF-a was secreted into the culture medium and purified by affinity chromatography. The production of the fusion protein in the culture medium unde...

The soil microorganism Myxobacter Sp. AL-1 regulates in a differential manner the production of five extracellular cellulases during its life cycle. The nucleotide sequence of a cel9-cel48 cluster from the genome of this microorganism was recently obtained. Cel48 was expressed in Escherichia coli to generate a His(6)-Cel48 protein and the biochemical properties of the pure protein were determin...