RESUMEN
Foot-and-mouth disease (FMD) is an acute, severe, and highly contagious infectious disease caused by foot-and-mouth disease virus (FMDV), which seriously endangers the development of animal husbandry. The inactivated FMD vaccine is the main product for the prevention and control of FMD, which has been successfully applied to control the pandemic and outbreak of FMD. However, the inactivated FMD vaccine also has problems, such as the instability of antigen, the risk of spread of the virus due to incomplete inactivation during vaccine production, and the high cost of production. Compared with traditional microbial and animal bioreactors, production of antigens in plants through transgenic technology has some advantages including low cost, safety, convenience, and easy storage and transportation. Moreover, since antigens produced from plants can be directly used as edible vaccines, no complex processes of protein extraction and purification are required. But, there are some problems for the production of antigens in plants, which include low expression level and poor controllability. Thus, expressing the antigens of FMDV in plants may be an alternative mean for production of FMD vaccine, which has certain advantages but still need to be continuously optimized. Here we review the main strategies for expressing active proteins in plants, as well as the research progress on the expression of FMDV antigens in plants. We also discuss the current problems and challenges encountered, with the aim to facilitate related research.
Asunto(s)
Animales , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/prevención & control , Antígenos Virales/genética , Vacunas ViralesRESUMEN
The major source of endogenous hydrogen peroxide is generally thought to be the respiratory chain of bacteria and mitochondria. In our previous works, mesosome structure was induced in cells during rifampicin effect, and the mesosome formation is always accompanied by excess hydrogen peroxide accumulation in bacterial cells. However, the underlying mechanisms of hydrogen peroxide production and the rationale behind it remain still unknown. Here we report that hydrogen peroxide can specifically accumulate in the mesosome in vitro. Mesosomes were interpreted earlier as artifacts of specific cells under stress through TEM preparation, while, in the current study, mesosomes were shown as intracellular compartments with specific roles and features by using quickly freezing preparation of TEM. Formation of hydrogen peroxide was observed in suspension of mesosomal vesicles by using either a fluorescence-based reporter assay or a histochemical method, respectively. Our investigation provides experimental evidence that mesosomes can be a novel site of hydrogen peroxide accumulation.
Asunto(s)
Escherichia coli/metabolismo , Peróxido de Hidrógeno/metabolismo , Orgánulos/metabolismo , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/ultraestructura , Microscopía Electrónica de Transmisión , Orgánulos/ultraestructura , Rifampin/farmacologíaRESUMEN
To survive, plants possess elaborate defence mechanisms to protect themselves against virus or pathogen invasion. Recent studies have suggested that plant mitochondria may play an important role in host defence responses to biotic stresses. In contrast with animal mitochondria, plant mitochondria possess a unique respiratory pathway, the cyanide-insensitive alternative pathway, which is catalysed by the alternative oxidase (AOX). Much work has revealed that the genes encoding AOX, AOX protein and the alternative respiratory pathway are frequently induced during plant-pathogen (or virus) interaction. This raises the possibility that AOX is involved in host defence responses to biotic stresses. Thus, a key to the understanding of the role of mitochondrial respiration under biotic stresses is to learn the function and regulation of AOX. In this article, we focus on the theoretical and experimental progress made in the current understanding of the function and regulation of AOX under biotic stresses. We also address some speculative aspects to aid further research in this area.