whooping cough (pertussis) is a highly contagious disease of the human respiratory tract, which is caused by bordetella pertussis. reemerge of pertussis in some highly immunized populations and divergency in gene order among several b. pertussis strains promoted this research to study the change of pertussis toxin (pt) and lipopolysacharide levels in response to the different environments. this...

Introduction: Despite high level of vaccination against pertussis‚ whooping cough has re-emerged as a health threat, especially in infants. This could be related to expansion of Bordetella pertussis with novel alleles for virulence factors including the pertussis toxin promoter, ptxP3. Compared to ptxp1 strains‚ ptxp3 strains produce more pertussis toxin which results in immune supp...

introduction: despite high level of vaccination against pertussis‚ whooping cough has re-emerged as a health threat, especially in infants. this could be related to expansion of bordetella pertussis with novel alleles for virulence factors including the pertussis toxin promoter, ptxp3. compared to ptxp1 strains‚ ptxp3 strains produce more pertussis toxin which results in immune suppression and ...

Whole-cell pertussis vaccine (wP) has been imperative and highly effective in preventing childhood deaths due to pertussis. Pertussis toxin is one of the virulence factors of Bordetella pertussis in all available pertussis vaccines. wP production in Razi Vaccine and Serum Research Institute is according to bioreactor culture of B. pertussis strains in B2 medium. The aim ...

  Whooping cough (pertussis) is a highly contagious disease of the human respiratory tract, which is caused by Bordetella pertussis. Reemerge of pertussis in some highly immunized populations and divergency in gene order among several B. pertussis strains promoted this research to study the change of pertussis toxin (PT) and lipopolysacharide levels in response to the different environments. Th...

a purification procedure of pertussis toxin (pt) from submerged culture of bordetella pertussis (b.pertussis) strain 134 using adsorption and affinity chromatography was discussed. the yield of the resulting pt was approximately 37.5mg/l of concentrated culture supernatant. the polypeptide pattern of the purified pt was investigated by sds-page and showed five bands between 11 to 26 kda using l...

Recently, concern has been voiced about the potential effect that antigenic divergence of circulating strains of Bordetella pertussis might have on the efficacy of pertussis vaccines. In order to model antigenic drift of pertussis toxin, a critical component of many pertussis vaccines, and to examine the effects of such drift on antibody neutralization, we engineered a strain of B. pertussis to...

background adenylate cyclase toxin (cyaa) is an important virulence factor of bordetella pertussis, the causative agent of whooping cough, and a potential component of acellular pertussis vaccine. objectives in the present study the impact of invasive cyaa on oxidative activities of phagocytes was compared with the other form of this molecule to investigate the activity of different parts of mo...

Pertussis toxin is a member of the AB(5) family of toxins and is composed of five subunits (S1 to S5) present in a 1:1:1:2:1 ratio. Secretion is a complex process. Each subunit has a secretion signal that mediates transport to the periplasm, where processing and assembly occur. Secretion of the assembled 105-kDa toxin past the outer membrane is mediated by the nine proteins encoded in the ptl o...

results the results showed that all the strains had the dominant allele ptxs1a. there were differences between the alleles of the clinical strains and the vaccine strain. conclusions in recent years, a significant increase in the incidence of pertussis has been reported worldwide. our findings regarding the allelic shift of the ptxs1 gene are similar to those reported in many european and ameri...