fusion of two genes at dna level produces a single protein, known as a chimeric protein. immunotoxins are chimeric proteins composed of specific cell targeting and cell killing moieties. bacterial or plant toxins are commonly used as the killing moieties of the chimeric immunotoxins. in this investigation, the catalytic domain of shiga-like toxin (a1) was fused to human granulocyte macrophage c...

cholera toxin b subunit (ctxb) is a homopantameric, nontoxic subunit of cholera toxin that is responsible for its binding to the cell and has been known as a mucosal adjuvant for vaccines that could increase homoral and mocusal immunity response. in this work, the ctxb gene was fused to the stxb gene from shigella dysenteriae type i a vaccine antigen candidate against this pathogen, by a nonfur...

Background & Objective: Persister cells are defined as a subpopulation of bacteria that are capable of reducing their metabolism and switching to dormancy in stress conditions. Persister cells formation has been attributed to numerous mechanisms, including stringent response and Toxin-Antitoxin (TA) systems. This study aimed to investigate the hypothetical role of TA systems in...

background: cholera toxin b subunit (ctb) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. the aim of this study was to compare the expression of native and mutant recombinant ctb (rctb) in pqe vector. methods: ctxb fragment from vibrio cholerae o1 atcc14035 containing the substitution of mutant ctxb for ami...

knowing the nucleotide sequence of the cholera toxin operon, we designed oligonucleotide primers for its-pcr amplification from local clinical isolates of v. cholerae. the resulting amplification product was cloned in a common puc18 vector. subsequently, a part of this operon encoding the cholera toxin bsubunit (ctb) was reamplified and cloned between the bamh1 and ecor1 sites of the same vecto...

Background: Cholera toxin B subunit (CTB) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. The aim of this study was to compare the expression of native and mutant recombinant CTB (rCTB) in pQE vector. Methods: ctxB fragment from Vibrio cholerae O1 ATCC14035 containing the substitution of mutant ctxB for ami...

pod borer is one of the main causes for yield loss of chickpea. therefore, breeding of chickpea for resistance to this pest is important. the use of cry toxin from bacillus thuringiensis is an effective strategy for producing of transgenic resistant chickpea to this pest. these toxins are able to become active in the midgut of larvae and disrupt the insect's digestive system. we studied the sta...

Vibrio cholerae, is the causative agent of cholera, that infects millions, annually. Chironomids are aquatic insects host V. cholerae. Toxigenic strains produce cholera toxin (CT) which main virulence factor causes symptoms. In contrast to other bacterial pathogens, cholerae produces CT when at low cell densities while hemagglutinin/protease (HAP) a high density-controlled gene. When behavior w...

The aim of the work was a comparative study expression main virulence genes in Vibrio cholerae strains classical biovar, typical and genetically modified V. , El Tor biovar. Materials methods . Natural toxigenic O1, biovar (J89, Pakistan, 1969), (M-887, Astrakhan, 1970) (301, Taganrog, 2011) were used as model ones. grown under optimum conditions for production cholera toxin toxin-coregulated p...