Phenol-soluble modulins (PSMs) are a novel family of small amphipathic, alpha-heli-cal peptides with strong surfactant-like properties. PSMs have multiple roles in staphylococcal pathogenesis and are considered as important virulence-associated factors. They may cause lysis of many eukaryotic cells, such as human neutrophils,erythrocytes and dendritic cells;induce the expression of pro-inflammatory cyto-kines;facilitate the structuring and detachment of biofilms;influence the expression of other genes. This re-view summarizes the classification,structure,regulatory effect on gene expression and biological function of PSMs. The potential avenues to target PSMs for drug development against staphylococcal infections are also evaluated in this paper.

Synthetic biology is a fast moving interdisciplinary branch of biology and engineering. To educate the next generation of synthetic biology scientists, the International Genetically Engineered Machine (iGEM) competition was established. In the past eleven years, many Chinese teams have participated in this event, but no thorough review and analysis have been carried out. In this paper, we collected the data and information of the Chinese teams from the iGEM website and analyzed the number, distribution and performance of Chinese teams in iGEM competition. We also described contributions made by the Conference of China iGEMer Community (CCiC) organization. The contributions to China higher education made by the iGEM competition were also summarized. Finally, we proposed several suggestions for the development of the iGEM competition in China. We envision the iGEM competition will continue to promote the innovative education and cultivation of the next-generation synthetic biology scientists in China.
China ; Genetic Engineering ; Synthetic Biology

Medical microbiology is an important basic subject in medical colleges.In view of the multifarious and abstract nature of the specialized course and the dull atmosphere in classroom teaching,we have adopted a doggerel teaching method in order to enliven the classroom atmosphere and improve the class teaching quality.After long-term teaching practice,it's been proved that the proper use of doggerel in classroom teaching can not only refresh boring theory and enhance students' learning interesting,but also simplify the complicated context and improve their memorizing ability and learning efficiency,posing a significant impact on the teaching effects of medical microbiology.

China ; epidemiology ; History, 19th Century ; History, 20th Century ; Humans ; Mycobacterium bovis ; Tuberculosis ; epidemiology ; history ; prevention & control

Objective To investigate the role of a transcription factor p 53 in dengue virus infec-tion.Methods A plasmid expressing siRNA specific for p 53 gene was constructed and then used to prepare HepG2 cell line with a suppressed expression of p 53 protein.The expression of p53 protein was detected by Western blot assay .A wild type control group and a siRNA group were set up by infecting wildtype HepG 2 cells and p53 low expressing HepG2 cells with type 2 dengue viruses,respectively.The virus titers in two dif-ferent cells were determined by plaque forming assay using Vero cells .Indirect immunofluorescence assay was performed to detect virus multiplication .The apoptosis of virus infected cells were analyzed by flow cytome-try.ELISA was performed to analyze the levels of IFN-βsecreted by infected cells from two groups .Results Compared with wildtype control group ,the cells in siRNA group showed a suppressed expression of p 53 pro-tein,suggesting that the HepG2 cell line with low p53 protein expression was successfully established .The vi-rus titer in supernatants of the cells from siRNA group was about 100-fold higher than that of wildtype control group at 24 hours after viral infection .Fluorescence activated cell sorting analysis showed that the numbers of green fluorescence labeled cells were remarkably increased in siRNA group .We speculated that p53 protein might play a role in the inhibition of dengue virus infection as indicated by the observed results .The numbers of apoptotic cells showed no significant difference between two groups .However,the level of IFN-βsecreted by wildtype HepG2 cells was six times higher than that of the cells in siRNA group .Conclusion p53 pro-tein might inhibit dengue virus infection through the activation of type Ⅰ interferon signaling pathway rather than enhance cell apoptosis .

Innovation education was introduced in medical microbiology teaching practice,including updating the innovative education concept,reforming teaching methods and means,constructing the teaching content system and practice platform adapting to innovation education.

The need of eight-year clinical students for bioinformatics undergraduate courses is described.In addition,the measures and experiences on textbooks choosing,teaching content assignment,teaching methods designing and test means innovation are also discussed.All these provide a reference implementation for the development of eight-year clinical bioinformatics courses.

Objective To identify the nanobaeteria in prostate fluid of patients with CPPS.Methods Expressed prostatic secretion(EPS)and urine specimens were collected by Meares-Stamey way from CPPS patients(n=100)and normal controls(n=100).The specimens were cultured and nanobacteria was identified by indirect immunofluoreseenee staining with rnonoelonal antibody.The morphological features were observed by using transmission electron microscopy(TEM). Results The positive rate of nanobaeteria in the EPS cdture of CPPS patients and controls were 43% and 5% respectively,with significant statistical difference(X2=39.58,P＜0.01).By TEM,the sizes of NB ranged from 100 to 500 nm and appeared eoccoid-ccccobacillary shape. Conclusion Nanobaeteria infection may exist in EPS of CPPS patients.

Objectives: To design the mutants of peptide antibiotics hPAB ? based on its molecular structure. Methods: The three dimension structure of hPAB ? was constructed by protein homology modeling method. The mutant molecules were designed and generated by PCR and inserted into pQE CP4 expression plasmid. The recombinant plasmids were identified by PCR and DNA sequencing and then transformed into Escherichia coli JM109 to express target fusion proteins. Results:Peptide hPAB ? shows one ? helical and three ? sheet in its structure. Its ? helical regions seem play a key role in the formation of active oligomer. Aside from positioning Thr 7 and Lys 10 into contact positions, the orientation of the ? helix is conserved about the oligome core, forming a ridge around it. Additionally, the dipoles of the helices would overlap to create a positively charged region near the core. These dipoles may be offset, however, by the presence of Asp 4 at the base of the helix. Two mutant molecules, hPAB ? 38 and hPAB ? 34, were designed by deleting N or/and C terminal 2～5 amino acid residues based on hPAB ? structure. The recombinant plasmids containing the mutants gene can express interest fusion proteins in E. coli JM109 successfully. Conclusions: Design, cloning and expression of the mutants of peptide antibiotics hPAB ? lay down the foundation for screening of the mutant of shorter peptide chain and having high or same antimicrobial activity.

Objective:To screen and clone a carrier molecule for the expression of small bioactive peptides at high levels. Methods: A carrier molecule, PaP3.30, was screened out from the genome of Pseudomonas aeruginosa phage PaP3 and its gene was cloned by PCR method and inserted into pQE 32 expression plasmid, this recombinant plasmid was named pQE PaP30. The peptide antibiotics hPAB ? gene was then inserted into pQE PaP30 and induced to express the fusion protein in Escherichia coli . The ability of PaP3.30 to express other bioactive peptides was evaluated by fusing 6 different origins, varies in sizes and isoelectric points selected peptides to it. Results: After fused to PaP3.30, the peptide antibiotics hPAB ? could express as fusion protein above 30% of total bacterial proteins. Six selected peptides were also expressed by the level of 35%～44% total bacterial proteins when fused to carrier molecule, PaP3.30. Conclusion: The new carrier molecular, PaP3.30, is versatile in the expression of small bioactive peptides.