scholarly journals CONSTRUCTION OF RECOMBINANT ATTENUATED BORDETELLA PERTUSSIS BACTERIA OF PTXP3 GENOTYPE

2018 ◽  
pp. 33-41 ◽  
Author(s):  
E. G. Semin ◽  
L. N. Sinyashina ◽  
A. Yu. Medkova ◽  
G. I. Karataev
Keyword(s):  
Bordetella Pertussis ◽  
Culture Medium ◽  
Genetically Engineered ◽  
Target Sequence ◽  
Vaccine Production ◽  
Dermonecrotic Toxin ◽  
Modified Dna ◽  
New Genotype ◽  
The Stability ◽  
Stability Of Structure

Aim. The construction of recombinant attenuated Bordetella pertussis bacteria of ptxP3 genotype and its genetic and biological stability characteristics. Materials and methods. During construction of recombinant attenuated bacteria of ptxP3 genotype virulent Bordetella pertussis bacteria of ptxP1 genotype were used as a recipient. PtxP1 genotype bacteria are used for whole cell pertussis (wP) vaccine production in Russia. Mutant bacteria B. pertussis 475 were received by crossing-over between chromosome comprising native copy of target sequence and its mutant copy in recombinant suicide plasmid transferred in recipient bacteria by conjugation. Genetically engineered construction of recombinant plasmids was conducted. The structure of modified chromosome locus of attenuated bacteria was determined by PCR and amplification fragments sequence. The stability of structure and characteristics of attenuated bacteria was defined after 15 passages of strains on culture medium and 5 passages in mice. Results. Isogenic attenuated ptxP1 B. pertussis 4M and ptxP3 B. pertussis 4MKS were constructed. These bacteria produce non-toxic pertussis toxin (PT) and do not produce dermonecrotic toxin (DNT). The promoter region of ptx operon contains mutation, typical for «new» genotype of circulating virulent bacteria and increasing PT production. The structure of modified DNA fragments and characteristics of attenuated bacteria did not change while storing and after passages on culture medium and in mice. Conclusion. Recombinant attenuated bacteria B. pertussis 4MKS of «new» ptxP3 genotype are constructed. Application perspectiveness of genetically engineered modification of isogenic B.pertussis bacteria for pertussis vaccines development is shown.

Impact of oxidative stress on protein production by Bordetella pertussis for vaccine production

2019 ◽  
Vol 151 ◽  
pp. 107359
Author(s):  
Vanessa Zavatti ◽  
Hector Budman ◽  
Raymond L. Legge ◽  
Melih Tamer
Keyword(s):  
Oxidative Stress ◽  
Bordetella Pertussis ◽  
Protein Production ◽  
Vaccine Production

scholarly journals Characterization of Diverse Subvariants of the Meningococcal Factor H (fH) Binding Protein for Their Ability To Bind fH, To Mediate Serum Resistance, and To Induce Bactericidal Antibodies

2010 ◽  
Vol 79 (2) ◽  
pp. 970-981 ◽  
Author(s):  
Kate L. Seib ◽  
Brunella Brunelli ◽  
Barbara Brogioni ◽  
Emmanuelle Palumbo ◽  
Stefania Bambini ◽  
...  
Keyword(s):  
Binding Protein ◽  
Genetically Engineered ◽  
Factor H ◽  
Serum Resistance ◽  
Dependent Manner ◽  
Bacterial Surface ◽  
Bactericidal Antibody ◽  
Human Sera ◽  
The Stability

ABSTRACTNeisseria meningitidisis a commensal of the human nasopharynx but is also a major cause of septicemia and meningitis. The meningococcal factor H binding protein (fHbp) binds human factor H (fH), enabling downregulation of complement activation on the bacterial surface. fHbp is a component of two serogroup B meningococcal vaccines currently in clinical development. Here we characterize 12 fHbp subvariants for their level of surface exposure and ability to bind fH, to mediate serum resistance, and to induce bactericidal antibodies. Flow cytometry and Western analysis revealed that all strains examined expressed fHbp on their surface to different extents and bound fH in an fHbp-dependent manner. However, differences in fH binding did not always correlate with the level of fHbp expression, indicating that this is not the only factor affecting the amount of fH bound. To overcome the issue of strain variability in fHbp expression, the MC58ΔfHbpstrain was genetically engineered to express different subvariants from a constitutive heterologous promoter. These recombinant strains were characterized for fH binding, and the data confirmed that each subvariant binds different levels of fH. Surface plasmon resonance revealed differences in the stability of the fHbp-fH complexes that ranged over 2 orders of magnitude, indicating that differences in residues between and within variant groups can influence fH binding. Interestingly, the level of survival in human sera of recombinant MC58 strains expressing diverse subvariants did not correlate with the level of fH binding, suggesting that the interaction of fHbp with fH is not the only function of fHbp that influences serum resistance. Furthermore, cross-reactive bactericidal activity was seen within each variant group, although the degree of activity varied, suggesting that amino acid differences within each variant group influence the bactericidal antibody response.

scholarly journals Nonlinear dynamics and robust control of sloshing in a tank

2018 ◽  
Vol 25 (1) ◽  
pp. 132-140 ◽  
Author(s):  
Tingting Zhang ◽  
Jianying Yang
Keyword(s):  
Nonlinear Dynamic ◽  
Closed Loop ◽  
Control Method ◽  
System A ◽  
Fluid Systems ◽  
Optimal Control Method ◽  
Guaranteed Cost ◽  
The Stability ◽  
Nonlinear Dynamic Modeling ◽  
Stability Of Structure

Sloshing is a complex nonlinear dynamic phenomenon which has a significant influence on the stability of structure–fluid systems. In this study, the dynamic equation of sloshing based on Hamilton principle is established and linearized into a state space equation. Considering the uncertainty of the system, a robust H infinite guaranteed cost control method is proposed to mitigate the response of fluid wave height to horizontal acceleration of the tank body. Simulation results are given to demonstrate the closed-loop performance of the nonlinear dynamic modeling and linear optimal control method.

Vibration Analysis for Pigging of Suspension Pipe Bridge

2012 ◽  
Vol 201-202 ◽  
pp. 669-672 ◽  
Author(s):  
Wen Ming Wang ◽  
Shi Min Zhang ◽  
Shang Na Song ◽  
Yin Li
Keyword(s):  
Theoretical Basis ◽  
Oil And Gas ◽  
Variable Load ◽  
Pipeline System ◽  
Liquid Loading ◽  
Dynamic Finite Element ◽  
Element Simulation ◽  
The Stability ◽  
Stability Of Structure ◽  
Strong Dynamic

Suspension pipe bridge is the key part of oil and gas pipeline system. Liquid loading during the pigging process will cause strong dynamic load of impact, thus the stability of structure will be destroyed. Paper establishes the pipeline pigging model suffered by the stress, analyzes the stress and vibration equation of the pigging pipeline. With the dynamic finite element simulation by the method of variable load, paper analyzes the vibration numeric of the pigging pipeline when the pig goes through the pipeline. The analysis of this paper provides the technical support and theoretical basis for pigging work.

The Influence of Different Concentration of Glucose on the Growth of Recombinant E.coli and Plasmid Stability

2013 ◽  
Vol 647 ◽  
pp. 185-189
Author(s):  
Ying Qian Xu ◽  
Chun Yuan Liu ◽  
Feng Ju Cai ◽  
Jun Yi Hu
Keyword(s):  
Culture Medium ◽  
Plasmid Stability ◽  
Biomass Concentration ◽  
Optimal Concentration ◽  
Good For ◽  
The Stability ◽  
Recombinant E.Coli

In this paper, the plasmid stability and the concentration of recombinant E.coli DH5α were investigated by adding glucose of different concentration at the beginning of fermentation. The result shows that glucose was good for the growth of recombinant E.coli DH5α and the stability of plasmid. The optimal concentration of glucose was 1g/L. The biomass concentration could be up to110.930g/L and the fraction of plasmid-carrying cell was about 99% in the optimized culture medium.

scholarly journals Punishment Effect of Prisoner Dilemma Game Based on a New Evolution Strategy Rule

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Dehui Sun ◽  
Xiaoliang Kou
Keyword(s):  
Nash Equilibrium ◽  
Prisoner's Dilemma ◽  
External Factor ◽  
Prisoner’S Dilemma ◽  
Evolution Strategy ◽  
The Stability ◽  
The Individual ◽  
Evolution Game ◽  
Stability Of Structure ◽  
Cooperation Structure

We discuss the effect of the punishment in the prisoner’s dilemma game. We propose a new evolution strategy rule which can reflect the external factor for both players in the evolution game. In general, if the punishment exists, the D (defection-defection) structure (i.e., both of the two players choose D-D strategy) which is the Nash equilibrium for the game can keep stable and never let the cooperation emerge. However, if a new evolution strategy rule is adopted, we can find that the D-D structure can not keep stable and it will decrease during the game from the simulations. In fact, the punishment mainly affects the C-D (cooperation-defection) structure in the network. After the fraction of the C-D structure achieved some levels, the punishment can keep the C-D structure stable and prevent it from transforming into C-C (cooperation-cooperation) structure. Moreover, in light of the stability of structure and the payoff of the individual gains, it can be found that the probability which is related to the payoff can affect the result of the evolution game.

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