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Abstract:[Objective] The aim of the present study was to isolate and identify the pathogen of Pelteobagrus fulvidraco eggs suffering from saprolegniasis, and study its asexual reproduction characteristics. [Methods] Filamentous fungal strains were first isolated from the Pelteobagrus fulvidraco eggs suffering from saprolegniasis using the traditional method. The pathogenic strain was further confirmed through artificial infection experiment, and identified by using morphological observation and phylogenetic analysis based on its ITS rDNA sequence. Additionally, its asexual reproduction characteristics was studied using single factor method. [Results] Four filamentous fungal strains were isolated form Pelteobagrus fulvidraco eggs with saprolegniasis, and strain HP was proved to be pathogenic to Pelteobagrus fulvidraco eggs by artificial infection. Therefore, morphology and asexual reproduction characteristics of strain HP were studied, and the phylogenetic analysis based on its ITS rDNA sequence was further conducted. The experimental results showed that the hyphae of strain HP were aseptate, transparent and seldom branched. Its zoosporangia were often clavate and renewed internally. Primary zoospore was discharged in Saprolegnia fashion. New sporangium generated from the base of old sporangium by the way of internal proliferation. Spherical oogonia were attached by monoclinous or diclinous antheridium hyphae. The ITS rDNA sequences of strain HP were naturally clustered with ITS rDNA sequences of Saprolegnia sp. in GenBank with 99% of homology, and had closest relationship with Saprolegnia ferax strain Arg4S (GenBank accession number: GQ119935). Combined morphological characterization with phylogenetic analysis based on ITS rDNA sequence, strain HP was identified as Saprolegnia ferax. In addition, strain HP could produce zoospores at 5 °C?35 °C and pH 4?10, its optimum temperature and pH for the zoospore production were 20 °C and 7, respectively. It was greatly inhibited by 5?25 mg/L formalin and 0.25?1.25 mg/L dithiocyano-methane. [Conclusion] The pathogen of Pelteobagrus fulvidraco egg saprolegniasis was isolated and identified in the present study, and its asexual reproduction characteristics was also determined, which could serve as a foundation for the control of Pelteobagrus fulvidraco egg saprolegniasis.

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Abstract:[Objective] We did this research to analyze the impact on the soil bacterial population of the transgenic carnation, which laid the foundation for the safety assessment of GM carnation. [Methods] Bacterial 16S rDNA gene clone libraries of GM and non-GM carnations were constructed, and the soil bacterial populations of these carnations were compared. [Results] The results showed Alphaproteobacteria, Betaproteobacteria, Planctomycetes and Acidobacteria were shared with GM and non-GM carnation. Some differences were found in Actinobacteria, Verrucomicrobia and uncultured bacterium clone. [Conclusion] The results indicated that high bacterial diversity was found in these GM carnation soil bacterial libraries, and the cultivation of genetically modified carnation did not have a significant impact on the soil bacterial community structure.

Abstract:[Objective] A bacterium MU2A-22T, which was isolated from 131-year-old volcanic deposits of Miyake-jima island (Japan), has been characterized for its capability of thiosulfate oxidizing. [Methods] The culture-based method was used to isolate and identify strain MU2A-22T for its phenotypic characteristics and taxonomic position. [Results] The strain MU2A-22T was Gram-negative, short rod- to coccus-shaped. This bacterium could utilize D-glucose, L-arabinose, gluconate, adipate and dL-malate as sole carbon source. Strain MU2A-22T was able to use thiosulfate as an energy source with the optimum concentration of 2.5 mmol/L. The optimum growth condition was 25 °C?30 °C and pH was 6.0?8.0 respectively. 16S rRNA gene sequence analysis indicated that this strain was closely related to Paracoccus solventivorans 6637T within Alphaprotebacteria (97% 16S rRNA gene sequence similarity). Its possess of the large-subunit gene of ribulose 1,5-bisphosphate carboxylase/oxygenase (rbcL) has also been identified. The cellular fatty acid profiles was characterized of the genus Paracoccus. The major fatty acids (>10%) were C18:1(74.7%) and C18:0(12.1%). DNA-DNA relatedness between strain MU2A-22T and P. solventivorans 6637T was 49.3%. G+C contents was 66.5%?66.7%. [Conclusion] As for the above results, strain MU2A-22T seemed to be a novel species in the genus Paracoccus with its accession number of GQ452286 and the name of Paracoccus scorialis sp. nov. was proposed.

Abstract:[Objective] The purpose was to develop some bacterial strains that could decolorize reactive black 5 effectively. [Methods] We isolated a bacterial strain which has strong decolorization ability, by the method of domestication with gradient concentrations, from activated sludge of Songjiang sewage treatment plant in Shanghai. [Results] According to its morphological, physiological characteristics and the analysis of 16S rRNA gene analyses for strain identification, >99.86 % of gene sequences in isolated strain RB5-M1 were similar to Aeromonas hydrophila compared to available gene sequences in the NCBI BLAST gene bank. [Conclusion] When the strain was cultivated in anaerobic cultural incubator (nitrogen 85%, carbon dioxide 6%), 35 °C, pH 8.0; it showed a decolorization rate performance of 94.1% for average value, 99.8% for maximum value.

Abstract:[Objective] Most microorganisms can not grow under organic solvents of high concentration due to their toxicity. To elucidate the mechanisms of organic-solvent-tolerant (OST) of microorganism, an OST mutant P. putida JUCT1 capable of growing in the presence of 60% (V/V) cyclohexane was obtained by gradient adaptation in cyclohexane. [Methods] Two-dimensional gel electrophoresis (2-DE) was used to compare and analyze the total cellular protein of JUCT1 when growing in the presence of 60% (V/V) cyclohexane or not. [Results] From 22 proteins whose intensity values show over 50% discrepancies under different solvent conditions, 3 high abundance protein spots were identified by MALDI-TOF/TOF spectra as 3-hydroxyisobutyrate dehydrogenase, protein chain elongation factor EF-Ts, and isochorismatase superfamily hydrolase, and their corresponding genes mmsB, tsf, and PSEEN0851 were expressed in the E. coli respectively. These the solvent tolerance of JM109 was significantly increase by these three proteins, particularly 3-hydroxyisobutyrate dehydrogenase. [Conclusion] In this work, proteomics analysis was proven to be an effective strategy for exploring OST mechanism of microbial cells. Importantly, this work provides molecular basis for constructing OST whole-cell catalyst for industrial applications.

Abstract:[Objective] This study is aimed to isolate and characterize antagonistic bacteria from soil, and evaluate their in vitro inhibition and control efficacy against Rhizoctonia solani, the causing agent of rice sheath blight in a green house. [Methods] Serial dilution method and dual culture technique on agar plate were used for screening bacteria. Strain identification was based on morphological and physiological characteristics, and phylogenetic analysis of 16S rDNA sequence. Control efficacy against rice sheath blight was evaluated by seed bacterization tests in a green house. [Results] An antagonistic bacterial strain against Rhizoctonia solani was isolated and screened from vegetable rhizosphere soil. The strain, designated as kwkjT4, exhibited excellent in vitro inhibition against the fungal pathogen. Its control efficacy against rice sheath blight was comparable to that of jinggangmycin. It was preliminarily identified as a strain of Chromobacterium pseudoviolaceum. The optimal growth conditions of the strain were as follows: pH 7.0, temperature 32 °C, incubation time 36 h. Inconsistence with those for the bacterial growth, the optimal conditions for accumulating inhibitory substances were pH 6.0, temperature 28 °C, and incubation time 48 h. [Conclusions] Strain kwkjT4 had potentials for the biological control of rice sheath blight. This is the first report on the antagonism of C. pseudoviolaceum against Rhizoctonia solani.

Abstract:[Objective] Chlorella high density training and lipid extraction condition optimizing. [Methods] Single factor experiments were used to research different mediums and environmental factors on Chlorella cell growth effects, and the ultrasonic extraction method was employed by orthogonal experiment for algae powder oil extraction conditions. [Results] The optimal condition of Chlorella ellipsoidea Y4 under heterotrophic culture to get high biomass were: BG11 medium with 50 g/L of glucose as the carbon source and 2 g/L KNO3 as the nitrogen source. The optimum culture temperature, shaking rate and the inoculums size were 29 °C, 180 r/min and 20%. By inoculating the preculture to a fermentation tank of 1 L capacity, we got dry cell weight 18.25 g/L. Based on the oil extraction condition optimization, Y4 lipid extraction yield increased from 25% to 60.2%, with lipid extraction yield raised by 35.2%. [Conclusion] Optimization of chlorella culture conditions and lipid extraction conditions were studied, and the result promoted the exploitation and utilization of chlorella resources.

Abstract:[Objective] To clone and express protein InternalinA (InlA) from Listeria monocytogenes (Lm) and prepare the polyclonal antibody against InlA. To provide basis for preparing the immunomagnetic beads which separated Lm efficiently and specifically. [Methods] Use biological software to design the primers of inlA gene, amplify the inlA gene from Lm by PCR and construct the gene into prokaryotic expression vector PET28a(+), then transform the gene into Escherichia coli BL21 and express optimally; purify the recombinant product InlA by nickel affinity chromatography, identify the recombinant protein by mass spectrometry analysis, and test the immunogenicity by ELISA. The purified protein is used as antigen for immunization of rabbit to prepare polyclonal antibody and the binding affinity between polyclonal antibody and Lm is determined. [Results] The recombinant InlA protein with relatively molecular mass of 92 kD was over-expressed in E.coli BL21. The InlA antiserum were obtained with a titer as high as 1:100 000. The antibodies had no cross reaction with other pathogenic microorganisms except Staphylococcus aureus. Immunofluorescent staining showed that it only binds to the cell surface of Lm but not L. welshimeri. [Conclusion] The polyclonal antibodies which binds to the cell surface of Lm specifically are prepared successfully. These results would provide basis for preparing the immunomagnetic beads which separated Lm efficiently and specifically.

Abstract:[Objective] A Streptomyces spiramyceticus WSJ-IA strain (herein designated as an isomycin I producer) with high proportion and high production of isovalerylspiramycin Ⅰwas obtained by cloning and expression of acyB2 (Regulatory gene) and ist (Isovaleryltransferase gene) into an isovalerylspiramycin Ⅰproducting strain. Taxonomic studies were carried out to define the engineered isomycin I producer and its original parent strain Streptomyces spiramyceticus F21. [Methods] 16S rRNA gene sequencing and five housekeeping genes (atpD、gyrB、rpoB、recA and trpB) coding proteins sequencing combining the traditional taxonomic studies, such as morphological, cultural, physiological and biochemical characteristics were performed for both strains. [Results] The Streptomyces spiramyceticus WSJ-IA and Streptomyces spiramyceticus F21 share highly similar phenotypes and 16S rRNA gene sequences as well as in the phenogenetic analysis of the five housekeeping gene protein sequences. While their 16S rRNA gene sequences and the five housekeeping gene protein sequences phylogenetically were located in different clades comparing with all other strains so far described. And the closely related strains with each gene coding protein were also different,none of them was as spiramycin producer reported. [Conclusion] Our results suggested that Streptomyces spiramyceticus F21 was possible a new Streptomyces sp. of spiramycin producer.16S rRNA gene sequence and five housekeeping genes (atpD、gyrB 、rpoB、recA and trpB ) coding proteins sequences could be served as genetic markers in identifying the engineered strain’s stability in long term of the commercial production.

Abstract:[Objective] Analyze the effects of iron deficiency on Streptococcus pyogenes, and find the key proteins in the iron acquisition systems. [Methods] Streptococcus pyogenes was cultured in THY medium with or without iron. Total proteins were extracted for the 2DE-gel analysis. The altered proteins upon iron depletion were identified by mass spectrometry. Further bioinformatics analyzed the relationship between key differentially expressed proteins. [Results] The 20 alterated protein were identified. With Cytoscape analysis of the betweenness of these proteins, 5 bottleneck proteins were detected. [Conclusion] The results showed that iron depletion affect the cellular biosynthetic processes, the metabolic process of compound containing nitrogen and the macromolecular metabolic process etc. This study laid a foundation for further studying the mechanisms of the iron metabolism in bacteria.

Abstract:Oligotrophic bacteria are widely distributed in natural environments, especially in oligotrophic environments where they play an important role in biogeochemical cycling. Recently, there have been an increased number of reports on oligotrophic bacteria due to application of molecular techniques. Isolation and cultivation techniques of oligotrophic bacteria, their ecological function and applications are among the frontier research topics in the fields of microbiology and environmental science. Here we summarized the findings in these aspects and reviewd the future development trends.

Abstract:Norovirus is the major cause of acute non-bacterial gastroenteritis worldwide and often lead to sever food safety incidents. Water is one of the important vectors of norovirus transmission. The paper gives an overview about the environmental resistance, concentration, detection and epidemiology of norovirus in water. At the same time, the outstanding problem and developmental direction of norovirus detection is also enclosed.

Abstract:Hand, foot, and mouth disease (HFMD) outbreaks have been reported in many areas, especially in Aria. Enterovirus 71 (EV71) is the major causative pathogen of HFMD in children and infants, its infection usually accompanied with severe neurological complication which causes high mortality. In recent years, the molecular biology study of EV71 and the progress of antiviral therapies development provide us new strategies for the treatment and prevention of EV71 infection. This paper reviewed the latest achievements in virology and antiviral agents of EV71, including drugs, vaccine, and RNA interference etc, which may be expected to serve as references for related research.

Abstract:Pathogen associated molecular patterns (PAMPs) recognized by host cell surface localized pattern-recognition receptors (PRRs) are pathogen conservation molecules. So far, a few pairs of characterized PRR/PAMP in plants provided useful models to study the specificity of ligand-binding and likely activation mechanisms. For example, recognition models of FLS2-flagellin, EFR-Tu (EF-Tu), CEBiP/CERK1-chitin and XA21-Ax21 have been extensively studied. The perception between PRR and PAMP triggers immune response (PTI) to resist pathogens. However, to successfully grow and proliferate on their hosts, virulent pathogens had to override the PTI, for which, these pathogens evolved a variety of strategies, such as injecting effector proteins into the plant cell or sequestering their PAMPs. Based on the knowledge on the interaction of PRR-PAMP, researchers are trying to engineer PRRs ( chimeras of PRRs) to develop new strategies in molecular breeding for achieving durability and a broad-spectrum disease resistance. We reviewed the recent findings about recognitions of PRRs-PAMPs, the engineered PRRs, and discussed the future prospects and several issues in researches on PTI.

Abstract:According to the specialties and laws of pharmacy industry, the idea and corresponding measures on the construction of productive practice-base for the higher vocational education of bio-pharmacy were researched and discussed in this paper. We also discussed the reformation of the higher vocational education and talent-cultivation mode with wok-integrated learning concerned with the practice-base. The college-leading construction and running mode is effective which was made for the practicing and innovative abilities cultivation of students and the skillful-talent cultivation.

Abstract:In the reform of medical microbiology teaching, Problem Based Learning (PBL) was compared to traditional tuitional methods. The result indicated that the PBL group’s scores of analysis problems, scores of theories and the total scores in examinations were significantly higher (P<0.01) than those of the traditional group. In the PBL teaching practice, major factors influencing teaching effect were found as the following: difficulties of role changing between teachers and students, student being easily puzzled by secondary problems, shortage of time and equipments, and defects in assessment methods. Therefore, corresponding countermeasures are provided in the present study to improve the teaching effect.