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Abstract:To quantify the population size of total methanogens changing with environments, season and depths of Zoige plateau, the plasmids and standard curves of species were constructed by using real - time absolute quantitative PCR. The concentration of the standard plasmids was 160 mg/L, with the coefficient being 0.992, and the amplification efficiency was 98.6%. The results showed that in April the population size of total methanogens in wetland ecosystem and grassland ecosystem were nearly the same. In wetland ecosystem, the population size of total methanogens decreased in the order of September, July, and April, while increased with the sampling depth in September and July, In grassland ecosystem, however, the population size of total methanogens did not change significantly with season and depth.

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Abstract:One demulsifying strain of Alcaligenes sp. S-XJ-1, isolated from the oil-contaminated soil, could grow at initial cultivation pH ranging from 6.0 to 11.0 and the optimum pH was observed at 10.0. Cultivated at initial pH 10.0, the biomass yield reached highest at 4.8 g/L and the emulsion breaking ratio achieved over 85% within 24 h when the biodemulsifier was dosed at 1000 mg/L. Meanwhile, this demulsifying strain S-XJ-1 had a higher cell surface hydrophobicity with ratio of microbial adhesion to hydrocarbon at 72.7% and water contact angle at 115° when it was cultivated at initial pH 10.0. To compare the demulsification process of demulsifiers produced at pH 7.0 and pH 10.0, kerosene-water model emulsion (W/O) mixed with the demulsifier was analyzed using Turbiscan method. Compared with the biodemulsifier produced under initial pH 7.0, the biodemulsifier produced at initial pH 10.0 remarkably increased the particle size of the dispersed phase, and then greatly improved the emulsion breaking rate.

Abstract:Most strains with capability of producing 2,3-butanediol (2,3-BDO) from glucose were isolated from different natural environment samples. The Strain 6-7 with high capability of producing 2,3-BDO was screened from the isolated strains and the production of 2,3-BDO reached 49.6 g/L. In addition to general morphological and biochemical characteristics, the strain 6-7 was identified by 16S rDNA sequence and systematic analysis. The results showed that 16S rDNA sequence of strain 6-7 had similarity of 99% with Bacillus subtilis strain BIHB332, suggesting that the strain 6-7 is one of Bacillus subtilis species. It is an environmentally friendly strain and Bacillus subtilis is generally regarded as safe microorganism used for industrial production. This strain showed the potential application in the future.

Abstract:The strain HDFE1, producing feruloyl esterases, was isolated from rotten wood fiber. It was identified as Penicillium citrinum Thom by study of morphology and rDNA ITS1-5.8S-ITS2 sequence and phylogenetic analysis. The optimum conditions for its growth were pH 6.0 and 30oC. At 30oC, pH 6.0, and 200 r/min for 60 h, the strain could produce feruloyl esterases at a yield 25 of 20.75 U/L.

Abstract:Twenty two bacterial strains with a capacity of denitrification were isolated from fish pond, of which eight strains have the high rate of denitrification while one strain named HS-N62 has the strongest effect of denitrification. The results showed that the denitrifying rate of strain HS-N62 reached 96% in 12 hours with initial nitrate nitrogen concentration of 140 mg/L and no nitrite nitrogen accumulation. The growth rate and characteristics of HS-N62 were further studied, and the results showed that the optimum growth temperature ranged from 30°C to 37°C, pH value from 6.0 to 8.0 and the optimal C/N ratio 10:1. Meanwhile strain HS-N62 could utilize a variety of carbon sources for growth. The most suitable denitrification condition for strain HS-N62 was confirmed by using a series of the orthogonal test. This denitrifying strain HS-N62 also has good ability of phosphorus removal, and the removal rate within 12 hours was up to 67.7% (at initial phosphate concentration 57 mg/L). Strain HS-N62 showed 99% 16S rRNA gene sequence similarity to many Pseudomonas strains. Based on the morphological characteristics, physiological and biochemical characteristics, the strain HS-N62 was identified as Pseudomonas sp.

Abstract:To identify reference strain CMCC(F)98003, which cited in Chinese Pharmacopoeia (CHP), polyphasic approaches including morphological features, Biolog identification system, ITS rDNA sequence, specific positions based on the ITS region and β-tubulin gene sequences analysis were used. Results indicated that CMCC(F)98003 was identified as Aspergillus niger and consistent with the scientific name in CHP. Although A. brasiliensis is close to A. niger, they have been classified as two different species and their morphology, phylogenesis and metabolic profilies are distinct. To maintain the consistency of international Pharmacopoeia, whether CHP replaces the new representative of filamentous fungi strain is worth studying.

Abstract:Two pairs of degenerate primers were designed according to the conserved amino acid sequences of several mitogen-activated protein kinase kinase kinases (MAPKKK) from basidiomycetes. Based on the conserved DNA sequence, which was obtained by nested degenerate PCR, a whole DNA sequence of MAPKKK of Volvariella volvacea (VV-MAPKKK) was obtained by blasting with Volvariella volvacea genome. VV-MAPKKK gene, containing 4 introns and codeing for a 1405 aa protein (VV-MAPKKK), is 4434 bp in length. The similarity of VV-MAPKKK compared with Hog-MAPKKK protein from Cryptococcus neoformans, Paracoccidioides brasiliensis and Cochliobolus heterostrophus is 58%, 57% and 56%, respectively. Phylogenetic analysis showed that VV-MAPKKK and Hog-MAPKKK protein homolog belong to the same clade. These data supported that VV-MAPKKK protein is a Hog-MAPKKK protein homolog from Volvariella volvacea.

Abstract:Soybean (Glycine max Merrill) seedlings were inoculated with arbuscular mycorrhizal (AM) fungi, Glomus mosseae, G. etunicatum, or/and soybean cyst nematode (SCN) Heterodera glycines in split-root systems. The dynamic changes of colonization of AM fungi, penetration rate of SCN, disease index, activities of peroxidase (POD), phenylalanine ammonia lyase (PAL), β-1,3-glucanase and chitinase in roots were analyzed. Both two arbuscular mycorrhizal (AM) fungi were able to decrease the disease index and penetration rate of SCN whether in one compartment or the other compartment of the split-root systems, the AM fungus and SCN inoculation in the same one compartment showed greater effectiveness than that in the two compartments. Compared with the treatment with SCN, the number of cysts in rhizospheric soil, cysts on roots and SCN in roots decreased by 47.4%, 58.9%, 46.6% and 50.5%, 67.0%, 57.5% respectively in the treatment inoculated with G. mosseae or G. etunicatum, and inoculated with SCN 3 weeks after AM fungal inoculation. It was indicated that AM fungi could significantly inhibit the development of nematode. The activities of the four enzymes in roots colonized by G. mosseae or G. etunicatum could be induced in a period of time. The AM fungus not only competed with SCN for colonization sites in one compartment, but also activated the defense mechanism of soybean, elicited the defensive enzymes in the other compartment. It was suggested that AM fungi can both systemically and locally antagonize SCN.

Abstract:Four mating types of basidispores were determined by using three-cycle mating system, three strains of Panus giganteus were used as test materials. Microscopical examination revealed that basidia of P. giganteus produced four basidiospores. The results of mating tests showed that P. giganteus has a tetrapolar heterothallism mating system. χ2 tests indicated that the distribution of the four mating types among spore monokaryons was in accordance with the 1:1:1:1 law of segregation in two strains, but one strain did not display the expected segregation ratio of basidiospores.

Abstract:The changing laws of bacteria community in different pit ages of luzhou-flavor liquor pit were analyzed using PCR-SSCP technique. The results were as follows: bands from No. 9 to No. 22 were showed clearly in all pit mud samples, which included 7 bands with higher dominant degree. But the changing laws of dominant degree among bands were different. Besides, the mean diversity index of all samples kept between 1.93 and 2.82. With the increasing pit age, the diversity index of samples from the same spots generally showed increasing trend. The similarity index of PCR-SSCP pattern of samples from different spots in the same pit was higher, between 0.63 and 1.00. While the similarity index of samples from different pit ages was lower, between 0.34 and 0.76.

Abstract:The antimicrobial mechanisms of tea polyphenol against Gram-positive S. aureus and Gram-negative P. aeruginosa were investigated by determining the changes in electric conductivity and total sugar concentration of broth for bacteria treated by tea polyphenol, as well as the changes in phosphorous metabolism and protein expression of bacteria. As the results showed, tea polyphenol had antimicrobial activity against S. aureus and P. aeruginosa, but stronger against the former. The facts that the electric conductivity and total sugar concentration of microbial broth increased indicated that tea polyphenol could damage the structure of cell membrane, which resulted in the increase of permeability of cell membrane and release of cell components. Besides, the consumption of phosphorous decreased in the tea-polyphenol-treated bacteria, which seriously influenced the synthesis of important cell components such as nucleic acid and phospholipid and energy metabolism. SDS-PAGE assay demonstrated that tea polyphenol could block the protein expression in bacteria, which influenced the cell structure composition and catalyzing activity of enzyme, and finally leading to the lost of normal physiological function of bacterium.

Abstract:To develop a more economical, simple and rapid detecting and differentiating Vibrio cincinnatiensis Differential Medium (VciDM), V. cincinnatiensis is one species of the major pathogens in seafood. Based on the specific enzyme systems and the corresponding metabolisms of V. cincinnatiensis, according to the resistibility to different antibacterial ingredients, VciDM was designed for the rapid separation, identification or detection of V. cincinnatiensis. The tests of color effects, plating efficiency, sensitivity and specificity were done to evaluate the efficiency of VciDM. The results showed that: VciDM had good selectivity and specificity. After incubation for 16?24 h at 37°C ± 0.1°C, the V. cincinnatiensis formed yellow colonies on VciDM. The other species of bacteria did not form colonies or formed green colonies on VciDM. VciDM showed a mean plating efficiency of V. cincinnatiensis cells of (82.14 ± 4.45)% and its detection limit was 101 CFU/mL. As compared with the conventional methods, VciDM used for isolating and detecting V. cincinnatiensis, which is simpler operation, lower cost, more convenient for observation, higher sensitivity and specificity. Accordingly, it is suitable for kinds of inspection agencies to detect V. cincinnatiensis, especially for the use in rapid detecting and monitoring V. cincinnatiensis in seafood in the primary production and processing plants. VciDM can be used to rapidly and initiatively detect V. cincinnatiensis, which is usefull to rake quick infection control measurees.

Abstract:A novel mutation approach, namely, the atmospheric pressure glow discharge (APGD) plasma jet driven by a radio frequency (RF) power, was used to treat the spores of Streptoverticillium mobaraense 03-10 for the selection of transglutaminase (TGase) producer. The mutant with high TGase production was quickly screened according to the formation of color on the double-layered plate and the different appearances of colonies. The total mutation rate was over 42.8% and the positive mutant rate was 20.6%. The obtained mutant G2-1 has good genetic and morphological stability and TGase activity reached 2.73 U/mL, which was higher 82% than that of original strain.

Abstract:Developing a new method to isolate and proliferate Chlamydia pneumoniae is meaningful. This new method begins with isolating peripheral blood mononuclear cell from blood samples, and use polyethylene glycol to break peripheral blood mononuclear cells which are positive with Chlamydia pneumoniae antigen, then centrifugate these broken peripheral blood mononuclear cells together with Hep-2 cells. After 7-day′s culture, these cells were broken by freeze-thaw cycle, and put into new Hep-2 cells, then centrifugated together to finish the first passage of Chlamydia pneumoniae. The second to the fourth passages were conducted in the same way. At the same time, we used Micro-immunofluorescence and PCR methods to detect Chlamydia pneumoniae in Hep-2 cells, also used a genus-specific, fluorescein isothiocyanate-conjugated monoclonal antibody to Chlamydia lipopolysaccharide, to stain inclusions, and got the IFUs counts of both imported and isolated strains after each passage. With the method of Micro-immunofluorescence, we found that Hep-2 cells centrifugated with peripheral blood mononuclear cells, Hep-2 cells of the first passage, Hep-2 cells of the second passage were all strong positive with Chlamydia pneumoniae antigen, Hep-2 cells of the third passage was positive, and the fourth passage negative. We also detected Chlamydia pneumoniae DNA existing in Hep-2 cells of the second passage with the method of PCR. So this simplified way can successfully achieve the isolation of Chlamydia pneumoniae from peripheral blood mononuclear cells. The phenomenon of degeneration appeared in the fourth passage of isolated strain, which was still superior to imported strain, but it will not largely affect the culture and passage of Chlamydia pneumoniae from peripheral blood mononuclear cells.

Abstract:Streptococcus pyogenes is a common pathogenic Gram-positive bacterium causing worldwide diseases with high morbidity and mortality every year. Metalloproteins have been highlighted for their essential roles in the metabolisms and virulence of pathogens. In this study, Cu-binding proteins of Streptococcus pyogenes were isolated by using immobilized metal ion chromatography and identified with LC-MS/MS. Totally, 21 proteins were identified and the network of interactions of the proteins was established. These proteins function in many biological processes such as translation, metabolism and ion transporting.

Abstract:We found a new Chinese record of the genus Trichoderma using the method of ITS and morporlogy from the east China. The species is Trichoderma koningiopsis/Hypocrea koningiopsis Samuels, C. Suarez & H.C. Evans sp. nov.. Percurrently proliferating phialides is the typical morphology of this species on PDA and CMD, while it doesn’t exist on MA.

Abstract:The capsular polysaccharides-producing Lactobacillus strain isolated from traditional fermented products was used in this study. Using Lactobacillus plantarum C88 as an original strain for treatment with nitrosoguanidine and screening with negative staining, the capsule-de?cient mutant strain was obtained, it was named L. plantarum C88M3. On the basis of the results of 16S rDNA sequence analysis, growth test and RAPD analysis, compared with the wild type strain C88, the mutant strain C88M3 showed the difference in genetic characteristics and capsular polysaccharide production. In this paper, a capsule-de?cient mutant strain was obtained by inducing mutation methods, and the results of this work would provide further insight into the function and mechanism of probiotic action.

Abstract:The technology of enzymatic cell disruption can not only improve the efficiency of intracellular products extraction, reduce energy consumption, but also reduce the usage of amount of chemical reagents, which is more friendly to environment. This paper reviewed the recent research progress of enzymatic disruption of microbial cells, such as bacteria, fungi, microalgae, protest and so on, the condition of industrialization as well as application prospect.

Abstract:Anaerobic ammonium oxidation (ANAMMOX) is a process that the bacteria of anammox convert NH4+-N into N2 with the NO2?-N as the primary electron acceptor under anaerobic condition. It is considered as a very promising nitrogen removal technology in future, because of its cost effectiveness and environmental friendly characteristics. Here, we review its mechanism, influence factors, application situation and the bacteria of anammox. Some suggestions are given for the development of anammox application in wastewater treatment.

Abstract:Lipid A is the major component of lipopolysaccharide, which forms the outer monolayer of the outer membrane in most Gram-negative bacteria. Lipid A is responsible for the bioactivity of endotoxin. After entering the host, lipid A can be recognized by immune cells, which may lead to diseases. The biosynthetic pathway of lipid A in bacteria is relatively conservative, but structure modifications can occur during its transport to the bacterial surface. These modifications differ in bacteria in order to adapt to different external environment. They are not necessary for survival, but are tightly regulated in the cell and closely related to the virulence of bacteria. This review summarizes recent advances on the modification of lipid A and its relationship with the virulence of bacteria. Furthermore, applications of such research in pathogen control, vaccine development, and fermentation industry are proposed.

Abstract:Some new progress about Ophiocordyceps sinensis were summarized and discussed, including the relationship between Ophiocordyceps sinensis and its host; genetic variation, cryptic species and associated species; somatic hybridization of high active compounds; its artificial culture and product standards and so on.

Abstract:We integrated a group of related experiments focusing on isolation, cultivation and mutation breeding of protease-producing bacteria into an experiment module and applied it in microbiological experiment teaching. The experiment module included preparation and sterilization of media, isolation of protease-producing bacteria, optimization of cultivation conditions, characterization of the strain, mutation breeding of the strain by UV exposure.

Abstract:Microbiology experiment is an important compulsory course in contemporary life science. In this paper, based on the students’ characteristics in the university for Ethnics and the features of bio-engineering major in our college, we discussed that microbiology experiment teaching system was divided into three types: Basic, Designing and Comprehensive. The principle of experiment teaching was that, with students’ open experiments and teachers’ supplementary assistance, students should fully function as the main body of experiment teaching. By normalizing experiments, cultivating self-learning skills, arousing students’ sense of originality, and students’ appliance capacity could be achieved.