Extraction, Purification and Identification of a Dexamethasone-degrading Enzymes Generated by Pseudomonas Alcaligenes / 生物医学工程学杂志

In this research a strain of isolated Pseudomonas alcaligenes which causes degradation of dexamethasone was acclimated further and its proteins of every position in the bacterium were separated by the osmotic shock method. The separated intracellular proteins which had the highest enzyme activity were extracted by the salting out with ammonium sulfate and were purified with the cation exchange chromatography and gel chromatography. The purified proteins which was active to cause degradation of dexamethasone had been detected were cut with enzyme and were analyzed with mass spectrometry. The results showed that the degradation rate to dexamethasone by acclimated Pseudomonas alcaligenes were increased from 23.63% to 52.84%. The degrading enzymes were located mainly in the intracellular of the bacteria and its molecular weight was about 41 kD. The specific activity of the purified degrading enzymes were achieved to 1.02 U x mg(-1). Its 5-peptide amino acid sequences were consistent with some sequences of the isovaleryl-CoA dehydrogenase. The protein enzyme may be a new kind degrading enzyme of steroidal compounds. Our experimental results provided new strategies for cleanup of dexamethasone in water environment with microbial bioremediation technique.

Exploration on the reform of experimental instruction for pathogenic biology and immunology / 中华医学教育探索杂志

To enable students to better grasp the basic skills of pathogenic biology and im-munology experimental teaching , and make full use of the characteristics of experimental teaching to train students' scientific quality and innovative consciousness , the reform of pathogenic biology and immunology experiment teaching was explored. Microbiology, Parasitology and Immunology experiment were integrated into an experimental course , and corresponding laboratory was set up to take an in-dependent experimental teaching. Through renewing experiment teaching idea, some measures were taken such as modularization and personalization of the teaching content, the establishment of a com-plete management system , writing a new experimental course to match the experiment , improving teaching methods and developing students' innovative experiments to improve their enthusiasm and in-terest for experimental class learning, thus enhancing their innovation ability.