Abstract:

Abstract:An extracellular chitinase from Thermomyces lanuginosus SY2 was produced when SY2 was grown in mineral liquid medium containing colloidal chitin as the only carbon source. The chitinase was stable at 50℃ for 1h, and the half-life time of the enzyme at 65℃ was 25 min. when it was kept at room temperature for 12 week, the chitinase activity was retained about 45% activity. The pH stability was kept in the range 3.0-9.0, and the enzyme was able to obtain 70% of the full activity, when the enzyme was incubated in the buffer (pH 2.5). The chitinase activity was enhanced obviously by metal ion Ca2+, but inhibited under the high content chemical reagents. The results suggested that the chitinase from Thermomyces lanuginosus SY2 was a novel enzyme due to its high activity and stability under the high temperature and acid environment, which make it applicable for biotransformation and other biotechnological purposes.

Abstract:Halotolerant bacterium NJ82 was screened from 129 strains of Antarctic sea ice bacteria. Optimum salinity for the growth of this strain was 12% (W/V), and the highest salinity tolerance was 18% (W/V). The 16S rRNA gene sequences homology and phylogenetic analysis showed that strain NJ82 belonged to the genus Pseudoalteromonas. The contents of protein, proline, Malondialdehyde(MDA)and cell membrane permeability growing at different salinity were analyzed. When salinity was in the range of 3.3%-12.0% (W/V), the protein and praline content both greatly rose with the increase of salinity, but the MDA content and cell membrane permeability varied little. When the salinity was above 12.0 % (W/V), protein content decreased, while MDA contents and cell membrane permeability significantly increased with the increase of salinity. These changes of important physiological parameters would offer significant information to understand the adaptation mechanism of sea ice bacterium to high salinity conditions.

Abstract:A facultative anaerobic bacterium. Bacillus TP-1 isolated from oil field wastewater could produce viscous polysaccharide and gas under oil reservoir condition at 55℃.The polysaccharide can produced 5.5 g/L and the output of gas was 22 mL/L. The viscous polysaccharide production was favorable in the lower concentration of CaCl2, MgSO4 and AlCl3. The results of core simulated tests showed that pressure was increased and oil recovery was enhanced by 7.37% after the bacteria injection. TP-1 strain has most of the desirable properties for microbial profile modification.

Abstract:The analysis results of reservoir characteristics, properties of fluids and microbiological characteristics of the formation waters of the Kongdian oilfield of the Dagang oilfield demonstrated that this oilfield is a high temperature ecosystem with formation waters characterized by low mineralization. The concentrations of nitrogen and phosphorus compounds, as well as of electron acceptors, are low. Oil and oil gas are the main organic matter sources. The oilfield is exploited with produced water-flooding. The oil reservoir was inhabited mostly by anaerobic thermophilic microorganisms, including fermentative bacteria (102 cells/mL-105 cells/mL) and methanogenic (103 cells/mL) microorganisms. Aerobic bacteria were detected mainly in the near-bottom zone of injection wells. The rate of sulfate reduction aried from 0.002 to 18.9 mg S2-/(L·d), and the rate of methanogenesis from 0.012 mg CH4/(L·d) to 16.235 mg CH4/(L·d). Aerobic thermophilic bacteria were capable of oxidizing oil with formation of biomass, the products of partial oxidation of oil (volatile acids), and surfactants. During growth on the culture liquid of oil-oxidizing bacteria, methanogenic communities produced methane and carbon dioxide, which also had oil releasing capabilities. Using various labeled tracers, the primary filtration flows of injected solutions at the test site were studied. Our comprehensive investigations allowed us to conclude that the method for microbial enhancement of oil recovery based on the activation of the strata microflora can be applied in the Kongdian oilfield.

Abstract:Plasma Membrane of Antarctic yeast Rhodotorula sp. NJ298 was purified from microsome in a two-phase aqueous system including Dextran T 500 and PEG 3350. The effects of the polymer and KCl concentration in the system on the plasma membrane partition were studied. The result indicated that the system with 6.0% (W/W) Dextran T 500 and PEG 3350, 4 mmol/L KCl was suitable for the plasma membrane isolation in Rhodotorula sp. NJ298. The electron micrograph stained with phosphotungstic acid and the purity identification analyzed by marker enzyme activities proved that the above two-phase system could obtain sealed positive plasma membrane vesicles with the purity of up to 78.2%. This paper was a basic about studying adaptation mechanism of Rhodotorula sp. NJ298 by isolation the plasma membrane.

Abstract:The cloning and expression of a β-galactosidase gene (TM_0310) from Thermotoga maritima MSB8 was studied. The gene consists of 2019 bp, and the translated protein encodes 672 amino acids and its molecular mass is approximately 78.972 kD. The homology analysis of the deduced amino acid sequences showed that the enzyme shared 95% identity with a putative β-galactosidase from Thermotoga petrophila RKU-1 and a β-galactosidase from Thermotoga sp. RQ2. The galactosidase activity was up to 2.08 U/mg after the recombinant E. coli BL21 was induced by IPTG. The crude lysate remained about 70% activity after treated at 80℃ for 10 min, indicating that the recombinant enzyme is thermostable and may be used at high temperatures.

Abstract:In this study, nearly 200 endophytic bacteria were isolated from different part of Huperzia serrata, over 60 bacterium with clear antifungal activity were selected from those cultures. Among them, strain H-6 exhibited the highest antifungal activity which was strongly inhibits the growth of many plant pathogenic fungi such as Sclerotinia scleroliorum, Fusarium graminearumt, Sclerotinia libertiana, Phytophthora capsici Leonia and Sesame fusarium wilt. According to the characteristics of morphology, physiology and biochemistry tests and the comparison of 16S rDNA sequence, the strain H-6 was similar to the Burkholderia. So strain H-6 was identified as Burkholderia sp. H-6. The results also showed that Burkholderia sp. H-6 was markedly different from Burkholderia cepacia that was applied widely in agriculture as antagonistic bacteria. The medium and culture conditions of the strain all were optimized by single factor and orthogonal ex-periments. In the investigation of the culture condition, growth was carried out in a basal medium (potato juice) and gradually supplemented with the various ingredients to be investigated. The major ingredients be-ing investigated included carbon sources and nitrogen sources. The optimal antifungal activity production condition is growth in a medium (potato juice with 2.5% mannitol and 0.1% NaNO3), initial pH 4.0 at 28℃.

Abstract:The IS-PCR and Rep-PCR were used to analyze 19 strains of Xanthomonas oryzae pv. oryzae from China,Japan and Philippines. Four specific primers, especially, IS1113 and ERIC could distinguish the strains from different countries. Using UPGMA analysis, most strains were in group 2 and 3. No relationship were observed between UPGMA groups and pathotypes.

Abstract:120 strains of endophytic bacteria identified by ERIC-PCR were isolated from wild and cultivated Glycyrrhiza uralensis plants which collected from Erdos Innermongolia province. The identified results indicated that Glycyrrhiza uralensis plants has plenty of endophytic bacterium in density and population, and the density is higher in root and leave than in stem. Partial sequence analysis of 16S rDNA gene of 82 strains indicated that these strains were in a high similarity with 19 known genus which belong to α、β、γ-Proteobacteria、Firmicutes and Actinobacteria. The dominant genus were Bacillus sp., Pseudomonas sp., Pantoea sp. and Serratia sp..

Abstract:A strain no. H5 isolated from Rhizophora stylosa Griff in Zhanjiang had a good antagonistic activity against Aspergillus niger, pathogen of Dracaena Sanderiana black-rot disease. It was identified as Bacillus licheniformis. Dual culture, mycelium growth rate and inhibitory zones were used to test the effect. Strong inhibition was shown against A. niger. Inhibitory ratios of H5 germ-free fermented filtrate on mycelium growth and conidial germination were 91.9% and 100% respectively. In addition, mycelia on the edge of antagonistic band became abnormal and over-branching. Meanwhile, a lot of vesicles appeared on the surface. When treated with heat, acid and alkali, the filtration of H5 was always with stable activity. Precipitate in 55% saturated ammonium sulfate dissolved in phosphate buffer solution maintained most of the activity after high pressure steam sterilization for 25 minutes. It was preliminarily considered as a kind of heat resistant protein.

Abstract:A pairs of primers were designed according to the fusion protein (F) gene sequences of canine distemper virus (CDV) in GenBank. A 369 bp fragment aimed signal peptide fragment of F gene was amplified. The PCR products from viscera samples, blood, urine of fur animals including foxes, minks and raccoon dogs, which collected in the years 2005-2007, were cloned to pMD18-T Vector and sequenced. We obtained 13 positive signal peptide fragments from wild-type strains. The results indicated there was obviously genetic diversity between the wild-type strains and CDV3 and other vaccine strains. The homology with CDV3 is 80.7%－83.2% in nucleotide, and 64.8%－71.3% in amino acid. The analysis for the hydrophobic regions indicated the function of signal peptide fragment may be changed. This study can offer academic data to research of CDV genetic variation and epidemiology.

Abstract:Based on the gene sequences encoding human antibacterial peptide LL-37 as registered in Gen- Bank (serial number in GenBank is CAA86115), using the preferential condon of P. pastoris, the antibacterial peptide LL-37 gene 141 bp in length was designed and synthesized. Especially a Kex2 signal cleavage site was fused in 5′end of the antibacterial peptide gene. The modified antibacterial peptide gene was clonedinto the pPICZa-A vector to construct the recombinant expression vector pPICZa-A-LL-37. The SacⅠlinearized plasmid pPICZa-A-LL-37 was transformed into P. pastoris X-33 by electroporation. The transformants were identified by PCR using R2 and 5’ AOX1 specific primers. The concentration of the secreted LL-37 was 206 mg/L. The new peptide, which has a weight of 4.5 kD, could remain its inhibition activity after being treated for more than 3 hours in boiled water. Agrose diffusion assay showed that LL-37 had broad-spectrum antibacterial abilities not only to Gram-negative bacteria but also to Gram-positive bacteria, the MIC to Staphylococcus aureus (CowanⅠ), E. coli K99 and Salmonella pullorum were 1.56 mg/mL, 3.12 mg/mL and 1.56 mg/mL, respectively.

Abstract:Rhodotorula glutinis (Fresenius) Harrison was irradiated with 80 MeV/u carbon ions. primary selection of yeast high in lipids-yield was performed with culture medium supplemented cerulenin, an inhibitor of fatty acid synthetase (FAS). The quantity of the lipids of selected strains was analyzed by phosphoric acid-vanillin reaction and traditional methanol-chloroform extraction methods. The results showed that the growth of Rhodotorula glutinis (Fresenius) could be inhibited efficiently by cerulenin. The inhibition rate was up to 98% at cerulenin concentration of 8.96×10-6 mol/L, which was considered suitable for mutant selection. Through the phosphoric acid-vanillin reaction, it was found that the quantity of the lipids was a positive linear relation with the OD at 530 nm. The positive mutant rate of primary selection reached to 65%. With the advantage of rapid and easy to perform, it can be considered as a good method to select yeast high in lipid-yield. By these methods, 2 mutant strains with lipid yield improved 90% compared with control was selected out.

Abstract:Two parental strains BY-14 and BY-6, with high leavening ability in lean and sweet dough respectively, were selected. Through spore production and separation, two haploids with opposition types were selected for cross-breeding. At last one hybridization strain was obtained, with good fermentation ability as BY-14 in lean dough and better than BY-6 by 25% in sweet dough.

Abstract:To assay the influence of dendritic cells (DCs) on the function of anti-infective immunity to Penicillium marneffei. DCs were generated from peripheral blood mononuclear cells (PBMC) and pulsed with Penicillium marneffei yeasts. DCs morphology was observed by the inverted microscope and cell surface markers of DCs were analyzed by flow cytometry. The concentrations of IL-12p70 were detected by ELISA. Mixed lymphocyte reaction was performed to assay the proliferation of T cells. The mRNA of CCR7 and CXCR4 were detected by the Real-time PCR quantifications. The acquired DCs exhibited irregular appearance and numerous long dendrites under light microscope. DCs and Penicillium marneffei yeasts were co-cultured for 24 h, numerous yeasts were observed inside the cells; an enhanced expression of the cell surface markers CD86、CD83、HLA-DR and CD40 were demonstrated; the expression of CCR7 and CXCR4 mRNA were also increased; the improved proliferation of T cells were observed in the mixed lymphocyte reaction. Yeasts-pulsed DCs secreted more IL-12p70 than that of non-pulsed, but less than that of LPS-pulsed DCs. DCs can engulf the Penicillium marneffei yeasts. When pulsed with Penicillium marneffei yeasts, DCs improved their expression of the co-stimulatory molecules and chemokine receptor CCR7、CXCR4, enhanced their capacity to process antigen. DCs play an important role in host defense against Penicillium marneffei infection. But the low level of the IL-12p70 production may lead to deficiency in the cell-mediated immunity against Penicillium marneffei.

Abstract:Actinobacillus succinogenes A3 was mutagenized by ultra high hydrostatic pressure for improving the production ability of succinic acid. The effects of pressure, rate of pressure changes and growth periods on the lethality rate of the strain were investigated. The strain in stationary phase was mutagenized at 200 MPa with the pressure changes at the rate of 50 MPa/min. As a result, a mutation strain Actinobacillus succinogenes B19 was obtained, and the concentration of succinic acid could reach 32.2 g/L, which was 17.9% higher than that of the original strain, and in the meanwhile the concentration of acetic acid was decreased by 11.5%. After six generation, the mutant also has good stability of descendiblity for succinic acid production.

Abstract:The fast development of the molecular biology and the further research on the nucleic acid set a solid foundation for the development of genosensor. Genosensor is the result of combining molecular biology with microelectronics, electrochemistry, optics and etc, which will build a bridge between the life science and the information science and become one of the most important technologies for DNA information analysis and detection. The working principle, classification of genosenor and the recent research on its application in the detection of functional genes of environmental microorganisms are discussed according to the latest literature. And it is pointed out that the application in the determination of microorganism functional genes in compost is an important development orientation of genosensor.

Abstract:With the constant rise of energy price, it has a great practical meaning of using lignocellulose to produce ethanol. Xylose is a kind of monosaccharide whose content is only less than glucose in most lignocellulosic hydrolysates. There is some difficulty of producing ethanol from lignocellulose by the traditional ethanol production strain Saccharomyces cerevisiae, because it cannot metabolize xylose. People have tried to use genetic engineering technology and cell fusion method to modify Saccharomyces cerevisiae to make it metabolize xylose and produce ethanol for many years. This review indroduced the progress in this field.

Abstract:Receptors are primary determinant of viral tropism and disease pathogenesis. Heparan sulfates (HS) are ubiquitous, polyanionic carbohydrate chains linked to core proteins in cell membranes and extracellular matrices of all eukaryotes. HS have also been demonstrated to function as receptors or co-receptors for a number of different viruses. To date, HS and four RGD-dependent integrins, αvβ3, αvβ6, αvβ1, and αvβ8 have been reported to serve as receptors for Foot-and-mouth disease virus (FMDV). Different receptors may be used to interact with host cells during FMDV infection. Studies on the structure and function of receptors are very important for understanding the interaction between host cells and FMDV. Here, We mainly reviews the progress on the biological characteristics of HS and its roles in FMDV infection.

Abstract:Swine influenza virus (SIV) is one of the major pathogens associated with swine respiratory disease. The co-infection between SIV and other pathogens make the epidemic situation even more complex, so far the SIV have spread throughout the world. Pigs play an important role in the evolution and ecology of influenza A virus. Due to their susceptibility to both avian and human influenza viruses, pigs have been postulated to serve as an intermediate host for the interspecies transmission of avian influenza viruses to humans or as a “mixing vessel” for the generation of human, avian, and/or swine reassortant viruses. Currently, three predominant subtypes of influenza virus are prevalent in pig populations worldwide: H1N1, H3N2, and H1N2, and these include classical swine H1N1, avian-like H1N1, human-like H3N2, reassortant H3N2 and various genotype H1N2 viruses. There is evidence suggesting that avian influenza viruses had been transmitted to pigs in China. Introduction of avian viruses into pigs co-infected with human H3N2 or swine H1N1 viruses provide a favorable opportunity for the generation of reassortants containing avian genes and would thereby pose a significant pandemic threat to pigs farming and human health.

Abstract:Predictive food microbiology is an emerging multidisciplinary area of microbiology. For the purpose of understanding the basic principles of predictive food microbiology, studying the usage of mathematics model in predictive microbiology, improving the efficiency of food sanitary detection and guarantee the food safety, this paper provides a review on different sorts of predictive model with emphasized on the tertiary model. It is included that the classifications of global modeling, research background, recent advances, operation approaches and also the analysis and evaluation of these models, which could be helpful for practical use. Baranyi & Roberts, Response surface, ComBase models are better than the others models.

Abstract:Atomic force microscope (AFM) has become a powerful tool for the characterization of bio-samples surfaces. In this paper, the working principles and methods of AFM were explained and the applications of the sample preparation, image analysis, force curve and the dynamic analysis in the biological field were reviewed.

Abstract:According to the practice and understanding in the process of microbiological experiment teaching, organizational thinking and form, the teaching contents and methods of this course are induced and summarized. It is put forward that the experimental teaching is organized as the form of research project, the students are principal part and the teachers play a leading role. Meanwhile the main problems of the teaching module and resolved measures are analyzed.

Abstract:Some measures were adopted in the fermentation engineering experiment teaching to explore its important role in the quality education. Good effect is achieved in the aspects of cultivating the ability of combining theory with practice, creativeness, thoroughness, and the spirit of hard-working and team cooperation of the students.

Abstract:PBL teaching method is a new mode of teaching which is originated from the West and implemented into China in recent years with an expectation that it would mainly develop the students’ self-learning ability, and enhance their skills of comprehensive thinking and solving actual problems. The author summarizes the practical experience of using PBL teaching methods in the theory teaching in Department of Medical Microbiology and Human Parasitology, China Medical University in the past three years, and then proved this method is very helpful to improving the students’ integrated thinking by analysis of sample .At the same time the results also suggested that the students showed high enthusiasm in discussing the cases. By this way, the students showed great subjective intiative in their studies.

Abstract:Base on the goal of the cultivation in the higher vocational education, this article provides some specific suggestions and recommendations?with the thorough?thoughts pertaining to the text materials, teaching format, test methods and construction of pharmaceutical microbiology technique training base in the class of pharmaceutical microbiology for the higher vocation education, They are: compiling text books with technology as a main stream, theoretical teaching serving practical teaching, training technical skills with modules, executing two to three alternating experiments arranged both scientifically and reasonably, utilizing an examination approach with a combination of oral tests, on-site operational evaluation, and written tests, constructing a realistic training base by modeling pharmaceurical production enterprise.

Abstract:In order to change the situations such as students’ passivity and low enthusiasm in the traditional experimental teaching of Microbiology and improve students’ comprehensive qualities, exploration and attempt on experimental teaching reforms including teaching contents, teaching modes, laboratory management and evaluation system of examination were done. Teaching practices showed that the normalized experiment syllabus based on the correct orientation of experimental teaching of Microbiology, the actualization of teaching mode of basic skill training-integrated experiment-designed experiment and the management of opening laboratory were effective measures in improving experimental teaching of Microbiology.

Abstract:A multiplex PCR assay for detection of Escherichia coli O157:H7 was developed by using 3 sets of primers that specifically amplify segments of the rfbE、fliC and eaeA genes. The target genes fragment of the PCR assay were 291 bp, 625 bp and 368 bp, respectively. Analysis of 30 strains demonstrated that this PCR system was specific. The detection limit of the PCR was 91.35 pg with genomic DNA. This multiplex PCR assay did not cross-react with the background Salmonella?typhimurium and could detect 1.4 CFU/mL in artificial inoculated meat sample after enrichment at 37℃ for 6 h. Three of 30 meat samples were detected positive. These results indicated that the multiplex PCR assay can be used for specific and sensitive detection of E. coli O157:H7.

Abstract:The effects of different carbon source, nitrogen source, proportion of carbon and nitrogen source, microelement and buffer salts on the growth of Lactobacillus casei Zhang isolated from Koumiss were studied. The enrichment medium for Lactobacillus casei Zhang was optimized by response surface methodology and its composition was glucose 20.9 g/L, soy peptone 10.45 g/L, yeast extract 10.45 g/L, K2HPO4 3.5 g/L, sodium acetate 14.6 g/L, sodium citrate 2.35 g/L, MgSO4?7H2O 1.0 g/L, MnSO4?5H2O 54 mg/L, CuSO4?5H2O 10 mg/L, tween 80 1.0 g/L. After cultivated in enrichment medium for 18h at 37℃, the living cells of Lactobacillus casei Zhang were 4.78×109 CFU/mL, which was about 10 times higher than in MRS (4.8×108 CFU/mL).

Abstract:The high molecular weight genomic DNA of yeast was extracted using three methods. Products were separated on agarose gel electrophoresis, quantified by spectrophotometer ND-1000 and restricted by EcoRⅠand MesⅠ. The result was shown that the genomic DNA extracted by modified benzyl chloride method was the best. The products of wild isolates supported it, too. This method was suitable for restriction of genomic DNA from yeast.

Abstract:The combination effect of high hydrostatic pressure and moderate heat on the inactivation kinetics of Bacillus coagulans spore in phosphate buffer and UHT (Ultra High Temperature) whole milk was investigated. The pressure come-up time and corresponding log-reduction of spore inactivation were considered during pressure-thermal treatment. Bacillus coagulans spore had a much higher resistance to pressure in UHT whole milk than in phosphate buffer. Survival data were modeled using the linear, Weibull and log-logistic models to obtain relevant kinetic parameters. The tailing phenomenon occurred in all survival curves, indicating the linear model was not adequate for describing these curves. The log-logistic model produced best fits to survival curves, following by Weibull model.

Abstract:Bacillus cereus TS02 is a functional strain separated by our laboratory. RAPD was used to analyse the specificity of TS02 in contrast to other five Bacillus bacteria (Bacillus licheniformis, Bacillus subtilis, Bacillus coagulans, Bacillus megaterium and Bacillus pumilus) that are highly homologic to TS02 according to the conventional taxonomy. A specific marker TSR1 (533 bp) was obtained, cloned and sequenced, a specific primer pair P1/P2 was designed based on the TSR1 sequence. P1/P2 can specifically amplify the objective band which is only in TS02 and not found in other control strains. The results showed that the specific RAPD marker had been transformed to the steady SCAR marker, and the specific SCAR marker can correctly detect the Bacillus TS02 in specie’s lever.

Abstract:The cholesterol oxidase producing strain Brevibacterium sp. DGCDC-82 was treated with NTG (1 mg/mL) under ultrasonicztion(200 W, 50 kHz). A red mutant named Brevibacterium sp. DGCCN-25 showed higher and stable production of cholesterol oxidase was obtained. The enzyme activity was increased by 140%, it is 1.24 U/mL.Then dealed with DGCCN-25 using the same method, two revertants were obtained, one was white and the other was rose pink. The enzyme activity of two revertants was obvious decrease, they are 0.17 U/mL and 0.69 U/mL.The results showed the positive correlation between COD acticity and red pigment producing by Brevibacterium sp.. The relativity model can be used as a method of screening for mutation and directed evolution.

Abstract:A Salmonellae sample offered by CNCA was detected by VIDAS、API 20E and SN 0170-92 respectively in the experiment. Each detected methods’ advantages and disadvantages was discussed in the paper.