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Eupolyphaga sinensis Walker is an important insect used in Chinese traditional medicine. In this study, we purified a 72-kDa anticancer protein, designated as EPS72, from this species using ammonium sulfate precipitation, ultrafiltration, CM Sepharose Fast Flow cation exchange, Q Sepharose High Performance (HP) anion exchange, Butyl Sepharose HP hydrophobic chromatography, and Superdex 75 gel filtration chromatographic techniques. EPS72 exhibited a potent anticancer activity against the human lung cancer A549 cell line (IC50, 18.76 μg/mL). Further study showed that EPS72 could induce A549 cell detachment and apoptosis, inhibit cell adhesion to fibronectin and collagen IV, and restrain cell migration and invasion. Moreover, EPS72 significantly decreased the expression of β1-integrin. This study suggests that EPS72 could potentially be developed as a novel anticancer therapeutic agent due to its possible antimetastatic activity.

Two-factor and three-level fractional factorial design was employed for evaluation of the effect of Glycine and Triton X-100 on the secretion and expression of ZZ-EGFP fusion proteins. Varying contents of glycine (0%, 1%, 2%) and Triton X-100 (0%, 1%, 2%) were added into shaking flasks, respectively, and supplied with appropriate volume of ampicillin (total 9 combinations; group at concentration zero serving as control) to promote more ZZ-EGFP diffuse into liquid culture medium. Fluorescent intensity in the culture supernatant was detected. A standard curve could be generated on the basis of fluorescent intensity and protein concentration. The expression level of ZZ-EGFP fusion proteins was estimated by checking the protein standard curve concentration fluorescene intensity. Results show that when the culture medium contains 2% Glycine and 1% Triton X-100, the expression level of ZZ-EGFP was able to be greatly increased. Further experiments revealed that absorbance value (A600) in the experiment group, whose culture medium contains 2% Glycine and 2% Triton X-100, is significantly lower than other groups in the present experiment. These results indicate that the culture medium containing appropriate quantity of Glycine and Triton X-100 is favourable to the secretion and expression level of ZZ-EGFP in gene-engineering bacteria Escherichia coli HB101.

The oxynitrilase in Chaenomeles Speciosa seed meal was used as the biocatalyst to synthesize a series of chiral methyl ketone cyanohydrins with satisfactory conversion and conspicuous enantiomeric excess. The optimized reaction conditions including the organic solvent, the ratio of biphasic solvents as well as the pH of the reaction system were investigated.

Aim: To study the relationship between primary structures of oligodeoxynucleo-tides (ODN) containing unmethylated deoxycytidyl-deoxyguanosine (CpG) dinucleotide motifs and their immunostimulatory activities in mouse spleen cells. Methods: A series of CpG ODN with different primary structures were synthesized. Their capabilities to stimulate mouse spleen cell proliferation were determined by [3H]thymidine incorporation assay. Cytokine (interleukin [IL]-6, IL-12, and IFN-α) secretion spectra induced by CpG ODN were assessed by ELISA. The ability of CpG ODN to activate natural killer cells was evaluated by standard 4 h 51Cr-release assay. Flow cytometry was utilized to examine the expressions of various lymphocyte surface molecules on diverse immunocytes. An effective CpG ODN for murine, ODN1826, was set as the template of modification and the positive control. Results: The immunostimulatory activities of CpG ODN with different sequences and compositions varied markedly, both in character and in extent. It was useless for improving the immunostimulatory activity of ODN1826 by simply increasing the functional hexameric CpG motif number, modifying the site of CpG motifs, or changing the distance between multi-CpG motifs. However, an addition of a self-complementary palindrome structure at the 3′-end, but not the 5′-end of CpG ODN, aroused marked improvement in its activity. Several designed ODN had superior comprehensive immunostimulatory properties compared to ODN1826. Conclusion: The immunostimulatory activity of a CpG ODN was relevant to its primary structure. It was useless for promoting immunostimulatory activity to simply change CpG motif number, space, or distance. The 3′-end palindrome structure of CpG ODN is associated with enhanced immunostimulatory activity.