Ao Jinxia

Expression of a Lysine-rich Gene in Bacillus subtilis 168

Lysine-rich protein gene (lys) was cloned from winged bean (Psophocarpus tetragonolobus (L.) DC), and cloned into prokaryotic expression vector pHT43, the recombinant plasmid pHT43/lys were constructed and then transferred into Bacillus subtilis168, upon IPTG induction, the recombinant protein was expressed, and the content of lysine was detected by HPLC. The result showed that lysine content increased by 9.85%. It was suggested that introducing lys gene into Bacillus subtilis 168 was an effective way to improve its nutrition quality.

SYBR® Green qPCR Screening Methods for Detection of Anti-herbicide Genes in Genetically Modified Processed Products

The use of genetically modified organisms (GMOs) as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize GMOs as food or food ingredients. Thus, analytical methods for detection of GMOs are necessary in order to verify compliance with labelling requirements. There are few effective screening methods for processed GM (genetically modified) products. Three anti-herbicide genes (CP4-EPSPS, BAR and PAT) are common exogenous genes used in commercialized transgenic soybean, maize and rice. In the present study, a new SYBR® Green qPCR screening method was developed to simultaneously detect the three exogenous anti-herbicide genes and one endogenous gene in a run. We tested seven samples of representative processed products (soya lecithin, soya protein powder, chocolate beverage, infant rice cereal, maize protein powder, maize starch, and maize jam) using the developed method, and amplicons of endogenous gene and transgenic fragments were obtained from all the processed products, and the sensitivity was 0.1%. These results indicated that SYBR® Green qPCR screening method was appropriate for qualitative detection of transgenic soybean, maize and rice in processed products.

Establishment of PCR-ELISA for Detecting Glyphosate Resistant Transgenic Soybean

Abstract A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows: the concentration of digoxin tag probe was 0.5 µmol · L −1 , the time of hybridization reaction was 15 min and the chromogenic reaction should last for 30 min. The sensitivity and the repeatability of our PCR-ELISA method were evaluated, and the results showed that it could be detected when the concentration of DNA template from transgenic soybean samples was 0.01% or higher, and the coefficient of variation of this method was less than 5% in our research condition. These results suggested that PCR-ELISA method establishment in this study had good repeatability and high precision for detecting the transgenic soybean samples.