Abstract:Lipopeptides produced by Bacillus subtilis JA antagonized a broad spectrum of fungal pathogens. Crude lipopeptides were extracted with methanol from the precipitate which was obtained by adding 6 mol/L HCl to the cell-free culture broth. The crude extract was run on Diamonsil C18 column (5 mm, 250 mm×4.6 mm) in reverse phase HPLC system to purify the lipopeptides. Inhibitory ability and IC50 values of lipopeptides towards various microorganisms were determined by agar diffusion method. The results showed lipopeptides exhibited strong inhibitory activity against some important plant pathogenic fungi, including R. solani and F. oxysporum. The ability of B. subtilis JA to antagonize against the growth of the post-harvest pathogen-B. cinerea was tested in vitro. Spore germination of B. cinerea was strongly inhibited in the presence of JA cell suspension. Furthermore, B. subtilis JA can produce antifungal volatiles which strongly inhibited the spore germination and mycelial growth of B. cinerea. As a biocontrol agent, the synergic effect of lipopeptides and volatiles may play a major role in controlling the pathogens by B. subtilis JA.

Abstract:The gene of hevein-like peptide AbAMP1 was cloned into the vector pPIC9 successfully. After linearized with restriction enzymes, the recombinant plasmid pPIC9-Ab was transformed into Pichia pastoris SMD1163 by electrotransformation. The transformants were screened on MD plate medium, and then identified using PCR method. The transformant AS16 with Mut＋ phenotype was used for inducing expression and other assays. A protein band of about 4.7 kD was detected on the gel by a tricine-SDS-PAGE analysis of induced culture supernatant, which indicates the protein content of the supernatant of culture after 72 h induction are almost the target peptide AbAMP1. A conspicuous inhibition band formed on a double-layered B. thuringiensis-containing plate where AbAMP1 gel band located after acid-native PAGE. This suggested the recombinant expressed AbAMP1 retains its natural antimicrobial activity. The supernatant of induced AS16 culture showed remarkable inhibitory effect on Fusarium oxysporum f. sp. cubense and Bacillus thuringiensis, B.

Abstract:258 yeast strains were isolated from the surface of grapes,collected from wine grape cultivation areas in Xinjiang, Gansu, Shaanxi, Ningxia and Shandong Provinces.These strains were identified mainly based on the 26S rDNA D1/D2 domain sequence analysis and morphological and physiological characterization. Among them, 26 species belonging to 13 genera were recognized. The dominant genera identified were Hanseniaspora (5 species), Candida (4 species), Pichia (4 species) and Issatchenkia(2 species). D1/D2 sequence variation were compared among the strains of the same species from different areas.

Abstract:To understand the enolase (eno) gene and its product in Streptococcus suis serotype 2 (S. suis 2), bioinformatics was adopted to analyze the whole genome sequence of the Chinese strain 05ZYH33 of S. suis 2. A highly homologous eno gene was unveiled by the genome-wide mining. A pair of specific primers was designed for the eno, and the target DNA fragment of 1.3 kb was successfully amplified using the genomic template of 05ZYH33. Subsequently, eno gene was inserted into pMD18-T vector, and then subcloned into prokaryotic expression vector pET32a, generating a recombinant expression plasmid pET32a::eno. The resulting plasmid was confirmed by direct DNA sequencing and transformed into E. coli BL21 (DE3) competent cells. Protein expression analysis showed that a 75 kD protein can be observed in 12% SDS-PAGE, indicating that the recombinant 6His-fused ENO protein can be produced in E. coli under the induction of IPTG. Western-blot experiment demonstrated clearly it shares strong specific antigenicity. Moreover, ELISA result suggested that ENO can occur on the surface of 05ZYH33 strain. Together, our data supported that ENO can function as a novel antigen, and may play pivotal roles in the severe infection of S. suis 2.

Abstract:Rapid species identification of Mycobacterium tuberculosis by rpoB gene micro array. Based on the gene micro array of rpoB, the standard strains of 21 mycobacteria and 8 non-mycobacteria ,126 clinical isolated of mycobacteria were detected by PCR-reverse dot blot hybridization assay. 360bp DNA fragment was amplified from all mycobacteria tested and was not found in all nonmycobacteria except hemolytic streptococcus and corynebacterium pseudodiphtheriticum. The result of specimens were detected by the probe which is composed of 21 oligonucleotide was that probe-Mycobacterium fortuitum cross hybridizated with Mycobacterium platypoecilus while the other probes were specific. The 89 strains of the all 126 strains isolated from clinical specimens were identified to be mycobacterium tuberculosis, the percentage was 70.6%(89/126), while the other 9 strains were identified to be unmycobacterium tuberculosis and the the percentage was 9.2%(9/98). Identification of Mycobacteria by rpoB gene micro array is a rapid and effective method which is of considerable value in clinical territory.

Abstract:To construct gene knock-out mutant of a two-component signal transduction system named 2148hk/rr in Streptococcus suis type 2 virulent strain 05ZYH33. Recombinant gene knock-out vector was constructed consisting of Spcr cassette with flanking homology regions to the target genes, the isogenic 2148hk/rr-deficient mutant was screened by allelic replacement. PCR analysis and Southern hybridization confirmed that the coding genes of 2148hk/rr were replaced completely by spcr cassette. Conclusion The mutant of 05ZYH33 2148hk/rr system was successfully constructed, which laid the foundation for farther research on the role of this two-component signal transduction system during infection.

Abstract:Three healthy women and three patients with BV were selected and diagonsed respectively according to the Amsel and Nugent criteria. Total microbial community DNA was extracted from their vaginal discharges, and 16S rRNA gene clone libraries were constructed. ARDAR fingerprinting patterns and sequences analysis of positive clones from each library showed that clones representing Lactobacillus crispatus and L. iners accounted for a major proportion respectively in the libraries for healthy women, where L. vaginalis and L. jensenii clones were present in a small amount. In the libraries for patients with BV, the microbial varieties increased remarkably, but both Gardnerella vaginalis and Atopobium vaginae clones constituted a greater portion, while Lactobacillus clones were not detected. It is therefore concluded that the vaginal microflora of healthy women is simple, predominated by single Lactbacillus species, and L. iners is one of the dominant species. The vaginal microflora of BV patients is complicated and various, but predominated by both Gardnerella vaginalis and Atopobium vaginae.

Abstract:An oxygen-tolerant denitrifying strain designated as H1 was screened by the procedures of shallow shaking and continuous aeration cultures. With the aid of an nnrS-gfp fusion responsive to nitric oxide (NO) and acetylene inhibition-GC procedure, it was shown that strain H1 was able to produce NO and N2O but not N2 under denitrifying conditions. Denitrifying processes were thus determined as NO3–→NO2–→NO→N2O, with N2O as the end product. Strain H1 could denitrify under shallow shaking conditions as well as in the initial atmospheric oxygen concentration ranging from 0~21%. Denitrification processed normally under continuous aeration at the rate of 2 L air per min in a 150 mL medium, but stopped under high aeration rate as 5 L air per min. 16S rRNA gene sequence revealed that strain H1 shared 98% similarity to its closet relative Ralstonia taiwanensis, the genus where denitrifying bacteria are frequently found.

Abstract:One slightly halophilic marine actinomycete strain JMC 06001 was isolated from a saline mud sample collected from the Island Naozhou in the South China Sea, near Zhanjiang, a city of southern China. The fermentation broth of strain JMC 06001 strongly inhibited the growth of Staphylococcus aureaus, Sarcina lutea, Bacillus subtilis, Escherichia coli, Micrococcus luteus and Proteus vulgaris. The combination of morphology, physiological and biochemical characteristics, chemotaxonomic data and 16S rRNA gene sequence analysis supported the view that strain JMC 06001 belong to a known species of the genus Steptomyces, S. peucetius. The strain studied grown well on most media tested, with white aeriel hyphae and pale yellow to pale brown substance hyphae. Yellow diffusible pigments were produced on oatmeal agar (ISP 3), potato extract agar and glucose/asparagines agar, and pale brown to deep brown diffusible pigments were produced on yeast extract/malt extract agar (ISP 2), glycerol/asparagine agar (ISP5), peptone-yeast ext-Fe agar (ISP 6) and nutrient agar. Growth occurred at 4 ℃~40 ℃ and pH 6.0~9.0, with optimum growth at 28 ℃ and pH 7.0. The tolerant range of NaCl was 0~1.5 mol/L, with best growth occurring in media containing 0.2~0.5 mol/L NaCl.

Abstract:A technology of L-cystine production was studied in this paper, which included microbial enzymatic conversion of DL-2-amino-?2-thiazoline-4-carboxylic acid (DL-ATC) to L-cysteine, subsequent oxidization of L-cysteine to L-cystine and its purification. The cells of Pseudomonas putida TS1138 could be repetitively used as the enzyme sources to convert the substrate DL-ATC to L-cysteine. After being oxidated by 2% dimethy-sulforide (DMSO), L-cystine could be harvested and further purified by the positive ion-exchange resin 001×7. High Performance Liquid Chromatography (HPLC) identified the purified L-cystine as having a total recovery of 78.55% and purity of 99.12%. This study demonstrated an efficient and convenient method for L-cystine production, which overcame the instability of enzymes, troublesome procedures and high cost of enzyme immobilization as contrasted to the traditional method. All in all, it provides a new approach for industrial production of L-cystine as well as L-cysteine.

Abstract:

Abstract:An extracellular α-amylase (AmyL) from a Bacillus sp WS-3L was purified 345 fold and had a recovery of 15.5%. The amylase was capable of hydrolyzing starch to yield a series of maltooligosaccharides. It was optimally active at 45℃ and pH values around 6.5 and showed stability at the temperature below 40℃ and pH 7.0-8.0. The amylase was inhibited by Cu2+、NH4+、Ag+、Hg+ and EDTA、SDS. Michaelist constants (Km) of the AmyL for were 2.81 mg/mL、8.37 mg/mL、1.80 mg/mL, and maximum velocity (Vmax) of the enzyme for soluble starch, amylose, amylopectin were 11.67μmol/(min·mL)、10.00μmol/(min·mL)、13.33μmol/(min·mL) respectively. It was suggested that amylopectin is the better hydrolysis substrate for the enzyme. It was observed that the adsorption and digestion of the enzyme on different raw starches was remarkably different. Raw corn starch exhibited high adsorption of the enzyme. It was suggested that the highly stable enzyme was able to be obtained and applied very fast by corn starch chromatography.

Abstract:The culture conditions of Saccharomyces cerevisiae sp. strain by 1.1b were optimized for the production of D-(-)-mandelate dehydrogenase which is useful for the asymmetric bioreduction of benzoylformate to form D-(-)-mandelate. The optimum medium (per liter)consistes of 60 g peptone, 30 g maltose, 0.5 g MgSO4, 0.01 g ZnSO4, 1.0 g KCl. After optimization of the culture medium, the enzyme production in shake flasks is enhanced from 2.56 to 20.21 U/L. The optimum fermentation conditions were determined as follows: medium volume 100 mL (i.e., 40% for a 250-mL shake flask), pH 6.5, inoculum size 10 %, temperature 30 ℃, and cultivation time 25 h.

Abstract:Producing cellulase conditions such as different temperature, inoculum size, liquid level and pH level by Trichoderma aureoviride in the shaking bottle were studied by orthogonal design method. The results showed that the main factor affecting the producing cellulase was temperature among the orthogonal conditions. The optimum conditions were as follows: cultivating solution initial pH was 6, cultivating temperature was 28℃, inoculation size was 8%, liquid level was 40 mL in 150 mL triangle bottle, rotation speed was 170 r/min.

Abstract:Five kinds of probiotic bacteria are immobilized and cultured continuously in simulated intestinal systems with corn fiber as the carrier. The biomass and the colonization in biofilm are investigated by selective culture methods and scanning electron microscope. Bifidobacterium longum TQ21-2-2, Lactobacillus acidophile CICC06005, Clostridum butyric TO-A, Bacillus mesentericus TO-A and Enterococcus faecalis T-110 can coexist stably . The biomass of five probiotics in the immobilized phase is greater than that of liquid in the continuous shake flask reactor. Five kinds of probiotic bacteria formed biofilm on corn fiber which be observed by SEM. Continuous culture of immobilized cells could be used better model than that of liquid , the model can be used to study for microecology and microecologocal agent.

Abstract:A 460 bp internal fragment of the AcrA gene from Vibrio alginolyticus strain HY9901 was amplified by PCR with designed primers and the unknown flanking sequence of 5′- and 3′- ends of the AcrA gene was finally characterized by inverse PCR and nested PCR. Sequence analysis showed the AcrA gene contained 1101 bp ORF encoding 366 amino acids and the deduced amino acid sequence of the precursor from Vibrio alginolyticus strain HY9901 showed significant homology with the putative protein of other Vibrio species. The AcrA shows 76%, 73%, 71% and 70% homology with V. vulnificus strain YJ016, V. parahaemolyticus strain RIMD 2210633, V. splendidus strain 12B01 and V. cholerae O1 biovar eltor str. N16961 respectively.

Abstract:One pair of primers was designed according to the N genes of canine distemper virus strains reported in GenBank. The N protein gene of CDV-FOX-TA was amplified with the primers by RT-PCR. The PCR product was cloned into pMD18-T. And the positive recombinant was identified, sequenced and analyzed. As a result, the large open reading frame of the N gene of CDV-FOX-TA included 1572 bp, which encoded 523 amino acids. The nucleotide homology of the N genes between CDV-FOX-TA and CDV Ondertepoort strain was 96.0%, and it was 95.9% between CDV-FOX-TA and CDV Convac strain. However, the nucleotide homologies of the N genes of CDV-FOX-TA and the CDV wild strains, was from 98.4% to 98.9%. A nine-peptide sequence in the N protein of CDV-FOX-TA was Tyr-Pro-Ala- Leu-Gly-Leu-His-Glu-Phe, which was T lymphocyte defined antigen and senstized target cells. On the basis of phylogenetic analysis, it implied that CDV-FOX-TA and the CDV wild strains had the same ancestor.

Abstract:Mutagenesis and screening of hydrogen-producing photosynthetic bacteria, Rhodobacter sp. R7 strain, was investigated by using the combination mutation of ultraviolet ray and LiCl and layer plating methods. A carotenoid mutant named R726 strain was obtained. The plate phenotype properties in carotenoid mutant were different from that of parent strains. Living cells spectra showed that absorption peak of 550 nm was appeared in carotenoid mutant, but not in parent strain. The absorption spectra of extraction of pigment further confirmed the difference of carotenoid composition between the mutant and parent strains. The result of TLC on silica gel plate showed that mutant has a lack of yellow carotenoid composition which occurs in parent strain. H2 productivity and biomass in carotenoid mutant was higher than that of parent strain. These results revealed that mutant has a modified carotenoid biosynthesis pathway.

Abstract:A series of experiments were conducted to study the mutation of Kloechera apiculata by many kinds of treatments such as UV and UV+LiCl. The optimal dosage disposal was determined: 15 W 30 cm under Ultraviolet irradiation for 20 s, UV+LiCl under Ultraviolet irradiation for 20 s and added LiCl 0.3% (w/v). One strain (UV20-13) which had obvious physiological characteristic was obtained. the incidence of blue and green mold of citrus was reduced by 25.56% and 10.00% in vivo experiment after 7 days respectively. The strain UV20-13 was tested by the experiments of subculture and dynamic growth, and the results showed that the strain UV20-13 was better than K.apiculata in the growth characteristics, and it did not appear retrogression, reversion mutation ect after subculturing 10 generations. Therefore the strain UV20-13 had genetic stability.

Abstract:Twenty Newcastle disease virus (NDV) strains were isolated from diseased chicken and geese in field outbreaks during 2005 and 2006 in some regions of Jiangsu and Guangxi, and the antigenic analysis of the all NDV isolates had been done based on the reaction spectrum with a panel of monoclonal antibodies to the HN glycoprotein. The entire ORFs encoding HN protein of these NDV isolates were amplified by RT-PCR successfully, cloned and sequenced. The resultant sequences of HN genes of 13 isolates of chicken origin and 7 isolates of goose origin were gained and analyzed. The results of reaction spectrum showed that there were some distinct differences in the antigenic epitopes among the 20 NDV isolates. And the sequences revealed that the coding regions of the HN genes of these isolates all consisted of 1716 nt characteristic of virulent strains of NDV, coding for 571 amino acids. Neucleotides sequence homology were found to be from 94.8% to 100% among 18 NDV isolates of genotype Ⅶ, and the neucleotides sequence homology be- tween all the isolates and the other genotype Ⅶ strains of recent years in China ranged from 92.1% to99.6%. The deduced amino acid sequences and the receptor-binding regions of HN proteins between the NDV isolates of chicken origin and of goose origin were compared and analyzed. The results showed that some unique amino acid substitutions were found in the genome of the NDV isolates, and the close genetic similarity provided evidence for epidemiological linkage between the NDV isolates of chicken origin and of goose origin in the same period.

Abstract:Fluoroquinolones are synthetic antimicrobial agents that are active against a broad spectrum of pathogenic Gram-negative and -positive bacteria by selectively inhibiting DNA gyrase and used in a wide variety in clinic because of their good pharmic kinetics and curing effects, thus causing environmental pollution. The physicochemical characteristics of fluoroquinolones and their environmental effect, identification, monitoring and bioremediation in soil were summarized in this paper.

Abstract:In this mini review, some research advance on Marinomonas from domestic and overseas was briefly summarized, mainly including of its classification、ecological distribution、functional genes and bioactive molecules. Furthermore, some suggestion and perspectives for further studies on Marinomonas were also proposed.

Abstract:The astaxanthin synthesized by Phaffia rhodozyma is a commercially valuable carotenoid. Related advances in the biosynthetic pathway of astaxanthin and the regulatory mechanisms of biosynthesis in Phaffia rhodozyma in recent years were reviewed. The innovating research aspects in related fields in China were also proposed.

Abstract:Agarases are glycoside hydrolases. They are grouped into a and b types, which hydrolyze a-1, 3 linkages and b-1, 4 linkages respectively. The paper is about advance in research of agarase including the research of biology, the classcification, the crystal structure, the catalysis mechanism and application of agarases.

Abstract:The growth predominance and culturing potential of transgenic Synechococcus sp. PCC 7002 with mouse metallothionein-Ⅰgene are characterized and expatiated by room temperature absorption spectra, photosynthetic oxygen evolution rate, growth kinetic parameters. The results show that the spectral absorption, maximum net photosynthetic rate and saturated light intensity of transgenic Synechococcus sp. PCC 7002 are higher than wild strain, whereas its the respiration rate and compensating light intensity are lower than wild strain. The transgenic cells exhibit a higher growth rate, and the maximum cell concentration is 1.74 times higher than wild ones when cultured in shaking flask. The air lift photobioreactor is suitable for bringing its growth potential into play.

Abstract:In view of the predominance problems in present experimental teaching of medical microbiology, we reformed the experimental contents and experimental teaching methods, to establish an entire experimental curriculum teaching system to be suitable for seven-year system and long educational system students, which manifests the creative teaching idea.

Abstract:This paper discussed the differences in teaching arrangement, material construction, teaching pattern, and teaching methods been used in medical microbiology teaching between China and the United State.

Abstract:Bilingual teaching is adapted to the development of higher education in china. Based on actual fact of college, teaching mode, evaluation and effect of bilingual teaching on medical microbiology were studied, which started with necessity of bilingual teaching to use original edition teaching material in English. The result would provide some gist to choice the suitable pattern of bilingual teaching for other subject of our college.

Abstract:Obtaining soil bacterial DNA of good quality is a key step in soil bacterial ecology study. A quick, efficient, sensitive and stably method of DNA extraction from soil were established by combining strongpoints of two kits ( Soilmaster kit and DNA IQTM kit). In addition, the 16S rDNA gene and T-RFLP (Terminal restriction fragment length polymorphism) were used in the analysis of soil bacterial community diversity and the result show that T-RFLP is a powerful tool for bacterial community study.

Abstract:In order to evaluate the effect of trehalose in protecting straw mushroom (Volvariella?volvacea) strain at low temperature, the viability, growth rate, chlamydospore, metabolites, and genetic fingerprinting of Volvariella?volvacea was tested. Results showed that straw mushroom strain remained viable at 4~6℃ at least for 8 months under trahalose preservation. HPLC analysis of metabolites and molecular fingerprinting indicated that trehalose didn’t change the genetics character of Volvariella?volvacea . The recovered straw mushroom strain stored at 4~6℃ for 8 months with the trehalose preservation kept viable and produce chalmydospores when stored in water for one month.

Abstract:A two-layer plate was developed for in situ detection of siderophore from halophilic archaea. Halophilic archaea could grow on the upper nutrient layer without addition of iron and excrete siderophore under iron-limited stress. The lower layer was the detection agar, which contained universal blue-coloured ferric-CAS complex. The presence of the siderophore was indicated by the decolorization of the blue complex, resulting in a yellow-orange halo around colonies growing on the upper nutrient layer, when the excreted siderophore penetrated from the upper nutrient layer into the lower detection agar. The results showed that the two-layer plate method was applicable to the detection of siderophore from halophilic archaea, which was more convenient and definite than former approach for halophilic archaea siderophore detection.

Abstract:Vibrio parahaemolyticus is an important food-borne pathogenic bacterium that widely exists in all kinds of seafood. As the traditional media and method were very costly-time and money, a new chromogenic medium (HKC vibrio) was designed in this assay. Through detecting the artificially contaminated samples and natural samples, the sensitivity, specificity and detection effect of HKC vibrio were studied and compared with CHROMagar vibrio and TCBS. The results showed that HKC vibrio had the same sensitivity as CHROMagar vibrio and TCBS, also had highly specificity. In conclusion, HKC vibrio was an invaluable medium which may improve the detection efficiency of Vibrio parahaemolyticus dramatictly.

Abstract:Pyrosequencing technology is famous for its application in detection of SNP site and DNA methylation. At the end of 2005, pyrosequencing technology was used to sequence the whole genome and it has become the most developed next generation high-throughput sequencing technonlogy. In this article, we introduce the theory, operation process and wide application field of the second generation genome sequencer FLX system provided by Roche