Directed evolution engineering to improve activity of glucose dehydrogenase by increasing pocket hydrophobicity.

Glucose dehydrogenase (GDH) is a NAD(P)+ dependent oxidoreductase, which is useful in glucose determination kits, glucose biosensors, cofactor regeneration, and biofuel cells. However, the low efficiency of the catalysis hinders the use of GDH in industrial applications. In this study, an analysis of interactions between eight GDH mutants and NADP+ is powered by AlphaFold2 and Discovery Studio 3.0. The docking results showed that more hydrogen bonds formed between mutants, such as P45A and NADP+, which indicated that these mutants had the potential for high catalytic efficiency. Subsequently, we verified all the mutants by site-directed mutagenesis. It was notable that the enzyme activity of mutant P45A was 1829 U/mg, an improvement of 28-fold compared to wild-type GDH. We predicted the hydrophobicity of the protein-ligand complexes, which was confirmed by an 8-anilino-1-naphthalenesulphonic acid fluorescent probe. The following order of increasing hydrophobicity index was deduced: GDH < N46E < F155Y < P45A, which suggested that the enzyme activity of GDH is positively related to its pocket hydrophobicity. Furthermore, P45A still showed better catalytic ability in organic solvents, reaching 692 U/mg in 10% isopropanol, which was 19-fold that of the wild-type GDH. However, its substrate affinity was affected by organic solvents. This study provides a good theoretical foundation for further improving the catalytic efficiency of GDH.

Analysis of Clinical Efficacy of Yiqing capsules and Cefaclor Tablets in Treatment of Simplex Anaphylactoid Purpura / 中国基层医药

Objective To investigate the efficacy of Yiqing capsules and Cefaclortablets in the treatment of simplex anaphylactoid purpura. Methods In this randomized,simple-blind, controlled study, all of 191 simplex anaphylactoid purpura patients,the throat secretion Group A βhemolytic streptococci antigen test was positive ,92 patients of control group were treated Cefaclor tablets and regular treatment,99 patients of test group were Yiqing capsules and Cefaclor tablets. Results After 10 days treatment,the clinical efficacy of the test group and the control group were 91.9% ,75.0% ,the test group was obviously higher than that of the control group(P ＜ 0.01), and the negative rate of the throat secretion Group A βhemolytic Streptococci antigen test of the test group was higher than that of control group, (P ＜0.01). the commencements of response of the test group was earlier than that of the control group(P ＜0. 01) ,the frequencies of recurrence of the test group were lower than that of the control group (P ＜ 0. 05).Conclusion Yiqing capsules combined cefaclor in treatment of simplex allergic purpura could improve efficacy, and reduce the treatment time.

Setting-up and Application of "Drug Use Monitoring Information Platform in Primary Hospitals" in Beijing Dongcheng District / 中国药房

OBJECTIVE: To standardize the management on drug use in primary hospitals in Beijing Dongcheng district so as to enhance the efficiency of drug administration.METHODS: A "Drug Use Monitoring Information Platform in Primary Hospital" comprising management information system on drug use,management system on information of drug wholesalers,drug monitoring management information system was established and its problems in the try-out were analyzed.RESULTS & CONCLUSIONS: The "Drug Use Monitoring Information Platform in Primary Hospital" still faced with the problems of legal basis,psychological concern,and construction of standard basic drug information database etc.However,its operation standardized the drug purchasing channel and management on drug use in hospitals of Beijing Dongcheng district and enhanced the drug administration level and efficiency,which thus deserves to be popularized throughout the country.