objectives: in present study we aimed to clone the lux i gene encoding n-acyl-homoserine synthase detected in biofilm forming clinical isolates of acinetobacter baumannii and study its expression in escherichia coli transformants. materials and methods: four a. baumannii hospital strains which demonstrated strong biofilm activity were selected in this investigation. the presence of lux i gene w...

introduction: gene expression and purification of luciferases from the firefly, lampyris turkestanicus, and optimization of cellular atp measurements were performed. methods: cdna encoding luciferases from lampyris turkestanicus was transferred from pqe30 vector into pet28a expression vector and pltu28 was built. newly constructed vector was expressed in e. coli xl1 blue and the recombinant luc...

Metallothioneins (MTs) are low molecular weight cysteine-rich proteins that bind to metals. Owing their high cysteine (Cys) content, MTs effective mediators of heavy metal detoxification. To enhance the binding ability MT from freshwater crab Sinopotamon henanense (ShMT), sequence-based multiple sequence alignment (MSA) and structure-based docking simulation (MDS) were conducted in order identi...

We describe the development of a novel positive-selection vector, RHP-AmpS, that is suitable for seamless cloning and high-level protein expression in Escherichia coli. In this vector, beta-lactamase (Bla) was rendered nonfunctional by replacing the codon for the C-terminal amino acid of the beta-lactamase gene (bla) with a stop codon. Insertion of a target gene in the correct orientation (tail...

Background: Cholera toxin (CT), responsible for the harmful effects of cholera infection, is made up of one A subunit (enzymatic), and five B subunits (cell binding). The release of cholera toxin is the main reason for the debilitating loss of intestinal fluid. Inhibition of the B subunit (CTB) may block CT activity. Objective: To determine the effect of anti CTB-IgY against oral challenge with...

introduction: hepatitis c virus (hcv) is the major cause of acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. because of increasing number of infected patients throughout the world, various studies are concentrated on development of high quality diagnostic tests and genotyping in various regions of the world. methods: in this study, we used rt-pcr to isolate and a...