RESUMO
Plant virus diseases are one of the major diseases restricting erop production.Timely identification of their pathogen and development rules is the prerequisite for effective control of their large- scale spread.However, long cycle, tedious steps and strict detection environment were the disadvantages existing in the detection technology of plant virus disease.In this study, Tobacco Mosaic virus (TMV) was used as a model to he extract UNA based on CMBs-ACPtmv , which was design based on the principle of complementary base pairing.Meanwhile, the experimental conditions were optimized and analyzed, including the preparation conditions of functionalized magnetic beads, the reaction conditions during extraction, and the sensitivity, stability and other properties of the method.The results showed the ability to capture RNA of CMBs-ACPtmv were best when prepared with 4 fxmol capture probe (ACPTMV ) and 0.08 mg carboxyl magnetic beads (CMBs) ; After 3 min of extraction, CMBs-ACPtmv has the best RNA extraction effect, but when the extraction temperature of CMBs-ACPtmv was changed, its extraction capacity showed no significant change; In the comprehensive performance evaluation, the sensitivity of CMBs-ACPjjjv can reach 2.5 ng/fxL, and the detection stability is good.Compared with conventional RNA extraction technology, CMBs-ACPimv has outstanding advantages in detection time and sample consumption.The functional magnetic beads extraction method established in this study is fast, safe and simple.It can achieve rapid extraction of plant virus RNA with simple equipment, which has a broad application prospect.
RESUMO
Objective To screen a thermostable urate oxidase-producing strain, optimize the fermentation conditions and study the enzymatic properties.Methods A urate oxidase-producing strain was screened from high temperature starter based on transparent circle method.Its 16S rDNA sequence was then amplified and analyzed.Meanwhile, the phylogenetic trees were built.Optimization of the fermentation conditions from this strain was carried out.The enzymatic properties of urate oxidase were studied.Results A urate oxidase-producing strain, named Bacillus subtilis ZX-6 by molecular identification, was obtained.The production of urate oxidase under the optimized conditons (135.9 U/L) was 133.7%higher than before.The optimum reaction temperature and pH were 45℃ and 7.6 respectively.The residual activity of urate oxidase at 37℃ for 48 h was still 17.2%.Conclusion The successful screening of a thermostable urate oxidase-producing strain and optimization of the fermentation conditions will lay a foundation for the further research.
