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.

Objective: To screen the best genetic engineering bacterium for the production of peptide antibiotic hPAB-? and evaluate its fermentation level in bottle. Methods:After analysis of the interest fusion protein expression levels of 8 recombinant bacteria containing 1-8 copies of human peptide antibiotic hPAB-? expressing plasmid respectively,2-5 copies expressing bacteria were chosen for the further study of their bacteria yield,expression forms of the target protein, dissolution of the inclusion bodies and the efficiency of fusion protein purification by affinity chromatography, then the best engineering bacterium with the certain copies of interest peptide expressing plasmid was screened out and its optimal fermentation parameters in bottle were also studied. Results:The recombinant bacterium transformed by 3 copies of interest peptide expressing plasmid was the best candidate for its bacteria yield (3.153 g/L) and fusion protein expression level (27.7%) were the highest among 1-8 copies candidates. The inclusion bodies of 3 copies target fusion protein could be easily dissolved by 8 mol/L urea and captured by Ni-NTA column. The elution of the fusion protein could be directly cleaved to monomer by adding 2 mol/L hydroxylamine, adjusting pH to 9.0 and incubating at 45℃ for 2 h. The optimal fermentation conditions of the selected recombinant bacteria were: culture the organisms with modified M9-CAA media at 37℃ and 160 r/min to (A 600 )≈2.5, then add IPTG to the final concentration 100 ?mol/L to induce the expression of target fusion protein for 5 h. Conclusion:The engineering bacterium containing 3 copies interest peptide recombinant expressing plasmid is the best candidate for the production of peptide antibiotic hPAB-?,and its fermentation parameters are confirmed.

Objective: Identification of the attachment site of phage PaP3 within the genome of Pseudo-monas aeruginosa PAS. Methods:The full genome of lysogenic bacteria was cleaved by Pst Ⅰ and produce a large fragment of more than 45 000 bp, which was subsequently digested by EcoR Ⅰ. Then the fragment containing DNA sequence of phage and bacteria was cloned into pFastBacTMHT A vector, and the result of sequencing indicated the right hybrid site attR. AttL was isolated by PCR on the base of integration mechanism. And then attP and attB were indentified according to the nucleotide sequences of attR and attB. Results:A sequence of 21 bp(5'-GGTCGTAGGTTCGAATCCTAC-3') was defined to be the core site of integration, which was located at t-RNAPro gene in the genome of phage PaP3 and t-RNALys gene in the genome of Pseudomonas aeruginosa PA3. The attP and attB flanked with a set of inverted repeat and direct repeat. Conclusion:The integrated site of PaP3 within the genome of PA3 was identified and characteriged, which could be of value in investigating the mechanism of integration and gene flow between different species in the natural world.