China
Africa
Explore chapters and articles related to this topic
Recombinant Antigens as Components of a Diphtheria-Tetanys-PerSüssis Vaccine
Published in Yoshikatsu Murooka, Tadayuki Imanaka, Recombinant Microbes for Industrial and Agricultural Applications, 2020
Andrew J. Makoff, Ian G. Charles, Neil F. Fairweather
The current vaccines against diphtheria and tetanus are based on inactivated, purified forms of the respective toxins (toxoids). Such toxoids induce high-titer circulating antibodies that neutralize the active toxin and prevent the symptoms of disease. In neither case is it necessary to immunize against the bacterium, as the lethal effects of the toxin are effectively neutralized by antitoxin vaccines. The vaccines are currently made by growing a toxigenic culture of CL tetani or Coryn. diphtheriae, partially purifying the toxin, and adding formaldehyde, which converts the toxin to the inactive toxoid. These vaccines are extremely effective when given as a course, usually of three injections in early childhood, followed by booster doses in later life. In contrast with these toxoid vaccines, the pertussis vaccine used in most countries is composed of cells of killed, inactivated B. pertussis. This vaccine is also very efficacious, although there is a small risk of adverse reactions, which has resulted in a reduced rate of vaccination against pertussis.
Medical Applications of Fiber-Optic Sensors
Published in Krzysztof Iniewski, Ginu Rajan, Krzysztof Iniewski, Optical Fiber Sensors, 2017
A chemiluminescent-based FOS was developed to detect cholera antitoxin IgA immunoglobulins. For this, fiber tips were immobilized with the cholera toxin B subunit. The cholera antitoxin analyte is marked by a secondary antibody labeled with horseradish peroxidase to generate chemiluminescent signal.71 Later, the same group used electropolymerization on ITO-coated fiber. This fiber-optic electroconductive surface modification is done by the deposition of a thin layer of indium tin oxide upon which biotin-pyrrole monomers were electropolymerized and then exposed to avidin. Avidin–biotin interactions were used to modify the fiber optics with biotin-conjugated cholera toxin B subunit molecules.72
Functional Metagenomics
Published in Vineet Kumar, Vinod Kumar Garg, Sunil Kumar, Jayanta Kumar Biswas, Omics for Environmental Engineering and Microbiology Systems, 2023
Kripa Pancholi, Anupama Shrivastav
ICE have the same integration site, resulting in strong competition for limited integration sites. Integration can occur at a single attachment site or can be random (Baranowski et al. 2018). An ICE once transferred to the new recipient cell integrates into the chromosome or evolves into an extrachromosomal element (Oliveira et al. 2017). A single-stranded DNA is then transferred to a new host, and the double-stranded elements through DNA polymerase are regenerated. The donor cell maintains the copy of ICE for the reintegration of ICE in chromosomes (Botelho and Schulenburg 2021). The ICE encodes the toxin-antitoxin and restriction-modification that triggers post-segregational damage to daughter cells (Koonin et al. 2020).
An invisible workforce in soil: The neglected role of soil biofilms in conjugative transfer of antibiotic resistance genes
Published in Critical Reviews in Environmental Science and Technology, 2022
Shan Wu, Yichao Wu, Bin Cao, Qiaoyun Huang, Peng Cai
In conjugation, mobile genetic elements, such as integrative and conjugative elements, are transmitted between bacteria (Ilangovan et al., 2015). Among conjugative elements, plasmids are arguably the most pertinent to the proliferation of ARGs given their potential to carry multiple resistance genes, their large size (median of 90 Kb), and toxin-antitoxin modules that ensure the plasmids are preserved in their microbial hosts (Pal et al., 2015). Conjugative plasmids can supply the machinery permitting the mobilization of DNA that is not self-transmissible, therefore greatly raising the potentiality for HGT of resistance determinants (Ramsay & Firth, 2017). Additionally, conjugative plasmids often carry other genes that contribute to microbial fitness, for instance, by coding for tolerance or novel metabolic pathways to heavy metals or disinfectants (McInnes et al., 2020). Antibiotic resistance determinants can therefore be co-selected under various circumstances as they share a genetic platform with other fitness determinants (Pal et al., 2015).
Formation mechanisms of viable but nonculturable bacteria through induction by light-based disinfection and their antibiotic resistance gene transfer risk: A review
Published in Critical Reviews in Environmental Science and Technology, 2021
Yiwei Cai, Jianying Liu, Guiying Li, Po Keung Wong, Taicheng An
High levels of (p)ppGpp further stimulate Lon protease and lead to the degradation of antitoxins (Figure 2). The toxins then become free and active, blocking the main cell activities. Manish et al. reported the role of the parDE2 TA system in Mycobacterium tuberculosis during the formation process of VBNC bacteria (Gupta et al., 2016). Based on conservative characteristics, a general analysis by Eitan et al. showed that TA systems may control the level of persistence through a redundant mechanism, and further demonstrated that the hipBA system triggers the onset and controls the duration of transient growth arrest, which indirectly enhances its role in the induction of VBNC bacteria (Rotem et al., 2010). The role of the toxins RelE and MazF from the common type II TA system have been known to induce VBNC bacteria as early as 2002. Specifically, RelE severely inhibits translation, while MazF inhibits both translation and replication (Pedersen et al., 2002). The ectopic expression of HigB, encoded by higB in the superintegron of V. cholerae, in E. coli inhibits its growth and induces the VBNC state (Christensen-Dalsgaard & Gerdes, 2006). The overexpression of the VapC toxin in M. smegmatis leads to the development of morphologically different oval VBNC bacteria, while overexpression of the VapB antitoxin prevents this from happening (Demidenok et al., 2014).
New automated peanut kernel slicing machine for enhanced stilbenoid production
Published in Journal of the Chinese Institute of Engineers, 2018
Resveratrol is a nonflavonoid phenol produced as an antitoxin by plants to defend against bacterial invasion. This antitoxin, or phytoalexin, is normally biosynthesized in the skin of grapes, peanut kernels (Burns et al. 2002), and Japanese knotweed roots as a secondary metabolite against fungal infection or stress. Polyphenols of resveratrol are insoluble in water but easily soluble in ethanol, ethyl acetate, and acetone. Resveratrol possesses multiple bioactive components with antioxidative, antibacterial, and anti-inflammatory functions as well as preventive effects against atherosclerosis and cardiovascular diseases (Dasgupta and Milbrandt 2007; Howitz et al. 2003; Huang et al. 2010; Lin et al. 2008b, 2008a; Lu et al. 2006, 2008; Berbée et al. 2013; Chen et al. 2013; Lee et al. 2014, 2015; Keylor, Matsuura, Stephenson 2015). Resveratrol has been detected in infected peanut hypocotyls, kernels, roots, leaves, pods, processed foods, tissue-cultured callus, sprouts, and root mucilage (Chen, Wu, and Chiou 2002; Liu et al. 2003; Wang et al. 2005; Sobolev, Deyrup, and Gloer 2006), indicating that peanuts are a potent biological source of resveratrol. The peanut kernel (Arachis hypogaea, L), sometimes called the longevity nut, is a prominent leguminous crop with a high content of vegetable protein. It is a major crop in Taiwan, with a plantation area of 18,610 ha and harvest of 46,809 t in 2016.