Abstract:[Objective] D190V mutation was introduced into the lipase from Rhizopus chinensis CCTCC M201021 by site-directed mutagenesis to improve its optimum temperature and the thermostability. [Methods] The mutant lipase D190V and wild-type lipase r27RCL were expressed in Pichia pastoris and the enzymatic properties were characterized. [Results] The optimum temperature of D190V was 5 °C higher than that of the wild-type, and the half-life (T1/2) of D190V at 65 °C exceeded that of r27RCL by 1-fold, other enzymatic properties were similar to r27RCL. [Conclusion] According to the analysis of structures, the reason of improved thermostability for the variant by only an amino acid substitution D190V was probably due to the improved stability of the α-helix located and the strengthened hydrogen bonding force in the protein structure.

Abstract:[Objective] To find out the mechanisms of yeast aging. [Methods] We performed continuous inoculation of Saccharomyces cerevisiae FFC2146 from generation to generation. We also observed the morphogenesis of Saccharomyces cerevisiae which has different generation numbers (2, 10, 15) through microscope, and measured absorbance in 600 nm to signify flocculation after sedimentation and determined residual glucose by DNS. Proteomic analysis of yeast cell wall proteins from the 2th and 15th generation was observed by Two-dimensional electrophoresis. [Results] Results showed that, the 15th generation yeast has rougher cell surface, higher flocculating velocity and lower metabolic level than the 2th and 10th generation, indicated that continuous inoculation accelerates yeast recession. Proteins were obtained by dithiothreitol and phenol abstraction. 309 proteins were detected and presented 11 changes responded to cell recession, 6 spots reduced by more than 2-fold in the 15th gel, 4 spots appeared in the 15th gel only and 1 spot appeared in the 2th only. [Conclusion] 11 Proteins from Saccharomyces cerevisiae cell wall changed after continuous inoculation 14 times, the changes of expression levels among these proteins were connected to yeast aging.

Abstract:[Objective] By adjusting carbon, nitrogen and phosphorus ratio and domestication model, to improve the ability of active sludge synthesis PHB. PCR-DGGE technology was used to study microbial diversity of domesticated flora. [Methods] In A/O alternate cycle SBR, we used sodium acetate as substrate, gradually improve carbon source concentration and limit concentration of nitrogen source, to create nutrition disequilibrium to gradually improve the content of PHB within activated sludge. [Results] When the COD reach 1 200 mg/L and COD/N/P=1 200/9.6/30, activated sludge synthetized PHB concentration reached the maximum of 64.2 wt% of the dry weight of cells. [Conclusion] In the process of domesticated sludge accumulation of PHB gradually increased, Sudan black, Albert staining and transmission electron microscopy images results showed improve carbon concentration and limit the concentration of carbon which domestication way promote the activated sludge accumulation PHB. DGGE was periodically used to identify the community diversity during the course of domestication and culture period. The population of the activated sludge was belonged to Acinetobacter, Bacillus, Bacteroides sp., Chryseobacteria sp. and proteobacteria.

Abstract:[Objective] For the study of the deposit pattern of the microbial fouling attaching on the surface of the heat exchanger, the deposit properties represented, respectively, through the alternating elliptical axis tube and pure tube were discussed by experiments. [Methods] The scheme was framed by taking iron bacteria as the strain, which is refined and purified from the natural Songhua River. In this work, the fouling dynamic simulation system was invited, together with the contrast experiments mean, it helped to achieve the influence analyses of fouling formation preformed by iron bacteria with the change of the flow rate and variation of water quality parameters under the industrial environments. [Results] The results demonstrated that, due to the increasing the flow turbulence caused by the alternating elliptical axis tube, the fouling precipitation amount in the alternating elliptical axis tube was less than that in the pure tube; moreover, the higher the flow rate was, the lower of the average precipitation amount of iron bacteria in the heat exchanger tube was. In addition, two parameters, including working fluids’ pH in the alternating elliptical axis tube and electrical conductivity, would increase first, and then tended to be stable; whilst the other parameters, involving the Fe2+, COD, DO’s content would show the decline tendency along with the accumulation of microbial fouling. [Conclusion] In general, the anti-fouling capacity of the alternating elliptical axis tube is superior to the pure tube, and the formation of the microbial fouling does have evident and remarkable effect on the water quality parameter of cooling water.

Abstract:[Objective] To discover the eukaryotic microbes diversity in sediment from a disused thermal vent in Yangbajing, Tibet A. R.. [Methods] To constructed the ITS-rRNA gene library of total DNA extracted from sediment by analyzed ITS-rRNA gene. Positive clones from the library were analyzed randomly by amplified ribosomal DNA restriction analysis (ARDRA). Phylogenetic trees based on eukaryotic ITS-rRNA gene sequences were built up by using MEGA 4.0 program. [Results] There were Ascomycota, Chytridiomycota, Basidiomycota, Cercozoan, Metazoan and uncultured fungus in sediment from Yangbajing thermal vent. Chytridiales sp., Physoderma maydis, Powellomyces sp., Candida parapsilosis, Zygosaccharomyces rouxii, Aureobasidium pullulans and Lecane bulla, all of them have not yet been reported to be inhabited in hot springs or thermal vents. [Conclusion] There were lots of eukaryotic microbes communities in sediment from the disused thermal vent in Yangbajing, Tibet A. R..

Abstract:[Objective] Several fed-batch fermentation modes were studied to investigate the effect on cell growth and astaxanthin synthesis of Phaffia rhodozyma. [Methods] Biomass, astaxanthin concentration and residual sugar concentration were detected when two Phaffia rhodozyma strains (JMU-VDL668 and JMU-MVP14) were fermented in 7 L bioreactor by batch and fed-batch culture. [Results] The highest biomass (64.6 g/L) of Phaffia rhodozyma JMU-VDL668, which was more than 2.2 times of batch culture, was obtained from DO-stat feeding culture; and pH-stat feeding culture brought the highest astaxanthin concentration (20.6 mg/L), which was 1.5 times of batch culture. Differently with the results of Phaffia rhodozyma JMU-VDL668, the highest astaxanthin concentration (414.1 mg/L) of Phaffia rhodozyma JMU-MVP14 was obtained by Pulse-fed culture, which increased by 200.2% compared with batch fermentation. Actually, biomass (38.5 g/L) and astaxanthin concentration (403.2 mg/L) were also improved significantly when DO-stat feeding culture was used, increased by 133.1% and 192.3% compared with batch fermentation respectively. [Conclusion] The production of astaxanthin had a significant effect due to different fed-batch fermentation modes. What’s more, the highest astaxanthin concentration of Phaffia rhodozyma JMU-VDL668 was obtained by pH-stat feeding culture while Pulse-fed culture was optimal for Phaffia rhodozyma JMU-MVP14 to product astaxanthin.

Abstract:[Objective] Different types, quantities and varying patterns of the AHLs released from pure cultured Pseudomonas fluorescens and Pseudomonas aeruginosa as the standard strains of Pseudomonas spp. were studied in this research. [Methods] AHLs in the pure culture solution were extracted via ethyl acetate and then identified through HPLC-MS-MS. [Results] The results showed that C4-HSL, C6-HSL, C8-HSL, 3-oxo-C10-HSL, 3-oxo-C12-HSL, 3-oxo-C14-HSL were the main signaling molecules released from Pseudomonas fluorescens while C4-HSL, C6-HSL, C8-HSL, C10-SL, C12-HSL, C14-HSL, 3-oxo-C8-HSL, 3-oxo-C10-HSL, 3-oxo-C12-HSL, 3-oxo-C14-HSL were the corresponding signaling molecules in Pseudomonas aeruginosa. [Conclusion] Quantities of signal molecules from the two strains were changing with time, when the number of colonies at 109?1010, reached the peak of the signal molecule. Also, significant differences of signaling molecules contents released from the 2 strains were found in this research.

Abstract:[Objective] In order to analyze the microbial community in the fermentation process of Chinese liquor, the interactions between Bacillus licheniformis and Saccharomyces cerevisiae which were crucial microorganisms to the quality of soy-sauce flavor liquor was studied. [Methods] By building the co-culture system of B. licheniformis and S. cerevisiae, the interaction was investigated. The molecular, heat-resistance activity and protease sensitivity of the inhibitors produced by S. cerevisiae were also analyzed. [Results] The growth of B. licheniformis could be inhibited, due to acidic environment caused by the growth of S. cerevisiae. Besides, S. cerevisiae also produced certain inhibitors (>10 kD), which is sensitive to heat and protease treatment, inhibiting the growth of B. licheniformis. [Conclusion] S. cerevisiae could result in an acidic environment and inhibit the growth of B. licheniformis. This work would promote the understanding of the microbial community in the Chinese liquor fermentation process.

Abstract:[Objective] In order to improve the detection efficiency of high-pathogenicity island (HPI) in avian Escherichia coli isolates, investigate the homology of its int genes and irp2 genes, and finally reveal the transfer regularity of HPI in avian E. coli. [Methods] Orthogonal experimental design was used to optimize multiple-PCR amplification system for irp2 and fyuA, which belong to the core genes of HPI, and avian E. coli clinical isolates were detected with this method. The genetic homologies of irp2 and int genes amplified from seven detected HPI-positive E. coli strains were analyzed. The distribution characteristic of int was analyzed comparing with the ERIC-PCR result of the seven HPI-positive E. coli strains. [Results] The core genes of HPI were specifically amplified by the multiple-PCR method. ERIC-PCR analysis shows that the degree of difference between the HPI-positive strains was higher than 5%. A great conservation (higher than 99% homology) of irp2 genes in HPI-positive E. coli strains was found, and all of the int genes were located in the vicinity of asn-tRNA, but not all of them were highly conserved. [Conclusion] We have established a multiple-PCR method which can be applied to the laboratory diagnosis test and epidemiological investigation of HPI, and suppose that the way of HPI horizontal transfer may be mainly based on the homologous recombination in the HPI-adjacent sequences.

Abstract:[Objective] Stability and antioxidant activity of the yellow pigments from Eurotium cristatum were evaluated. [Methods] Taking preservation rate of the pigments as an indicator, the effect of different temperature, light and pH on the stability were assessed. Antioxidant activity of the yellow pigments was investigated by three methods: reducibility, DPPH· scavenging activity and inhibition of erythrocyte hemolysis induced by H2O2. [Results] The results of stability test showed that preservation rate of the pigments was more than 98.88% after low-temperature treatment for 7 days and declined as the temperature increasing. Light, especially sunlight, resulted in an obvious loss of stability of the pigments. Better stability of the pigments was observed in the range of pH 2?10. However, preservation rate was lower than 46.22% at pH 12. At low concentration the pigments had higher reducibility, DPPH· scavenging activity and inhibition rate of erythrocyte hemolysis than VE, and the hemi-inhibitable concentration (EC50) to DPPH· was lower than 50 mg/L. [Conclusion] The yellow pigments from Eurotium cristatum had better stability in the condition of heat and acid but alkali and sunlight were not. What′s more, the pigments had higher antioxidant activity.

Abstract:[Objective] This study was aimed to isolate and identify the actinobacteria with antitumor activity isolated from a soil sample collected from the Ba-yi town, Nyingchi, Tibet, China. [Methods] Actinobacteria were isolated and purified by agar plate dilution method planting in Gause 1 and glucose/asparagines agar media. To test the biological active effects in vitro of the actinobacteria fermentations and its’ crude extracts, we used MTT assay with 5 human tumor cell lines to monitor the antitumor activity, paper-dish method with 7 indicative microorganism strains (bacteria and fungi), and 4 antibiotics to detect the antimicrobial activity and resistance. The polyphasic taxonomies of the antitumor active strains were studied according to morphological, cultural, physiological, biochemical characteristics and 16S rRNA gene sequence analysis. [Results] We isolated 29 actinobacteria strains of which 6 strains with good antitumor activities were obtained (20.7%). All of the crude extracts of the 6 strains had remarkable inhibiting effects against the 5 human tumor cell lines and different degrees of antimicrobial activity against the indicator microorganisms. The crude sample of 4 of them had the inhibition rate of more than 80% on Hela cell line. Only one active strain had good tolerance for 4 kinds of antibiotics. Taxonomic studies showed that all of the 6 antitumor active strains were related to Streptomyces. These 6 strains may be variants of the three known Streptomyces species (Streptomyces galbus, Streptomyces mirabilis, Streptomyces olivochromogenes) respectively. [Conclusion] The actinobacteria in Ba-yi town of Nyingchi are rich in Streptomyces with antitumor activities and may be a potential microbial resource for antitumor drugs.

Abstract:[Objective] Leptospira spp., including the pathogenic Leptospira interrogans and the saprophytic L. biflexa, can synthetise abundant bacterial storage in cell bodies, which may be one of the primary reasons why Leptospira spp. can survive in barren environments for a long time. In this study, the leptospiral polyhydroxybutyrate (PHB) storage was examined qualitatively and quantitatively. The major functional genes for PHB synthesis were complementarily annotated by the genome analysis. The integrity of the PHB synthesis pathway was verified by the molecular biology methods. This study laid foundation for further research on the relationship between the leptospiral storage synthesis and the stress tolerance. [Methods] The leptospiral PHB storage was determined qualitatively and quantitatively by the lipid-specific Nile Red dyeing and the concentrated sulfuric acid oxidation-ultraviolet spectrophotometer method. The storage synthesis genes were identified by the bioinformatics methods (BLAST and InterProscan/InterPro2Go) through the homolog analysis and the functional domain search. The expression of the predicted PHB synthesis genes were verified by gene cloning, sequencing and quantitative RT-PCR. [Results] By the Nile Red dyeing and the oxidation-colorimetric assay method, Leptospira spp. was proved to synthetise PHB, a common bacterial storage. The synthetic amounts of L. interrogans and L. biflexa were 42%?45% and 64%?68% of their dry weights, respectively. Though no integrated PHB synthesis pathways were defined in the leptospiral genomes, the homologs of the major functional genes for PHB synthesis (phbC) were identified in the genomes of L. interrogans and L. biflexa by the comprehensively bioinformatics analysis in this study. By cloning, sequencing and qRT-PCR, most of the PHB synthesis genes (phbA/B/C) were proved to be transcribed in Leptospira spp., which suggested that the leptospiral PHB synthesis pathways were primarily integrated, and some highly-expressed genes may be the main functional genes involved in the leptospiral PHB synthesis. [Conclusion] L. interrogans and L. biflexa all can synthetise PHB storage and have primarily integrated PHB synthesis pathways.

Abstract:[Objective] In this paper, the influence to bacteria intracellular macromolecular biosynthesis after antimicrobial peptides BF2-A and BF2-B, two analogues of buforin Ⅱ, interacted with E. coli had been researched. [Methods] The influence of peptides on the synthesis of bacterial DNA and RNA had been determined by ultraviolet spectrophotometry. The influence of peptides on the synthesis of bacterial total protein had been determined by Coomassie brilliant blue method. Inhibition of β-galactosidase and alkaline phosphatase activities of E. coli cells by antibacterial peptides had been measured by ONPG and PNPP, respectively. [Results] Peptides didn’t primarily influence the synthesis of DNA and there was a lag phase. Thus the preferential inhibition of biosynthesis of RNA and protein appeared to be the primary target of BF2-A/B and the effect of the peptides on DNA-synthesis appeared to be secondary. On the same concentration, BF2-B caused a more marked inhibition of RNA-synthesis than BF2-A. Interestingly, BF2-A induced a more remarkable inhibition of protein synthesis than BF2-B. The results of activity measuring of two endocellular enzymes, β-galactosidase and alkaline phosphatase, further proved that the biosynthesis of protein was inhibited. [Conclusion] Both peptides binding to nucleic acid didn’t primarily inhibit the replication function of DNA, but primarily inhibit the transcription function of gene. Moreover, the preferential inhibition of protein-synthesis mostly embodied at the translation level.

Abstract:[Objective] Exopolysaccharides produced by Bifidobacterium animalis RH were fractionated into two peaks by anion exchange chromatography, named as EPSa and EPSb. The aim of the study was to obtain the optimal conditions for high yield of total EPS, especially EPSb. [Methods] In this paper, the effects of medium types, nitrogen source, carbon source, carbon concentration, initial medium pH, cultivation temperature and cultivation time on the yield and proportion of EPSa and EPSb were evaluated. [Results] The highest yield and favorable proportion were obtained in PTYG broth medium (pH 7.0) containing 5% sucrose when B. animalis RH was anaerobically cultivated at 35 °C for 60 h. [Conclusion] Under these conditions, the yield of EPSa and EPSb were 0.982±0.003 g/L and 0.312±0.001 g/L, respectively.

Abstract:[Objective] Hydrogen production and the exoelectrogen activity under complex substrate microbial electrolysis cell (MEC) are of great significance to its application in wastewater treatment. [Methods] The characteristics of exoelectrogens were investigated with the single-chamber MEC fed by the artificial dairy wastewater under different applied voltages in this study. [Results] The maximum current could reach up to 261 A/m3 and the volumetric H2 production rate reached to 0.048 m3 H2/m3 d with the applied voltage of 1.2 V, which was increased by 467% and 700% compared with the applied voltage of 0.4 V, respectively. The COD and protein removal could be achieved by 59% and 74%, respectively. The COD removal at 1.2 V was improved by 22.5% compared with that at 0.4 V. The PCR-DGGE community analysis demonstrated that Geobacter sp., one of well-know exeoelectrogens, existed in anode colonies as the dominant bacteria. There might be a synergies relationship between exoelectrogens and non-electrochemically active bacteria. [Conclusion] MEC can use dairy wastewater as fuel, achieve the purpose of efficient degradation and produce hydrogen gas at the same time, which provides research ideas for the practical application of MEC.

Abstract:Cyanobacteria are the only prokaryotes that are able to produce clean, renewable fuel hydrogen gas through oxygenic photosynthesis. The hox-encoded bidirectional Ni-Fe hydrogenases in some cyanobacteria species, capable of evolving hydrogen gas, has continued to attract interest due to their application potential. However, the regulation of their enzymatic activity remains largely unexplained. In this review, we summarized the structure, ecological distribution and expression regulation of Hox hydrogenases in cyanobacteria. Besides, we briefly introduced our recent studies on two hypothetic genes, ssl2420 and sll1225 in the hox operon of Synechocystis sp. PCC 6803, and discussed the possible roles of this gene pair in the differential expression of hox components.

Abstract:The heat shock response (HSR) in Escherichia coli is de?ned as the cellular response to temperature increase. A set of proteins are synthesized when E. coli is stressed with elevated temperatures. These proteins are known as heat shock proteins (Hsp) many of which are molecular chaperones, proteases and folding factors. Some of heat shock proteins can promote proper folding of proteins and the degradation of misfolded proteins. This paper introduces the characterization and regulation of the heat shock proteins, the application of heat inducible secretion vector pHsh-ex to recombinant protein expression, and the resent research progress on chaperone co-expression systems.

Abstract:Osmotic stress seriously affects the physiological function of lactic acid bacteria, which has caused some difficulties in the development process of some related products. In recent years, compatible solutes as the functional substances in response to the osmotic stress of lactic acid bacteria have received extensive attention. In this paper, types, properties and transport mechanisms of the osmotic stress-related compatible solutes for lactic acid bacteria are detailed and the prospect of the follow-up research is also made.

Abstract:The multidrug resistance of ESBL-producing bacteria poses a serious problem in the clinical therapy. In recent years, some studies indicate that integrons are closely linked to the antibiotic resistance in bacterial pathogens. Class I integron is the most ubiquitous among clinical microbes and remains the focus of numerous investigations. Integrons are specialized genetic elements capable of capturing exogenous gene cassettes and ensuring their expression under the action of integrases. Integrons are natural cloning and expression systems in the function of integration and excision. It has been demonstrated that integrons can continuously capture and integrate multiple genes that confer resistance to antibiotics. The conjugative plasmids and transposons associated can serve as vehicles for the transmission of drug-resistance genes, leading to the serious trend of multidrug resistance. This paper reviews the structure of class I integron, the integration of gene cassettes by class I integron and the relationship between class I integron and multidrug resistance in ESBL-producing bacteria.

Abstract:The effect of electronic concept maps on promoting the teaching of Medical Microbiology was investigated. The students were divided into two groups, test and control groups. The test group was required to accomplish the electronic concept maps and questionnaire, then took the same closed-book exam with the control group. The students’ test scores were analyzed by SPSS (solutions statistical package for the social sciences) and the completed questionnaire were discussed and evaluated. In the course of the study, teachers made the scaffolds of the concept maps and the students in the test group completed the mappings on them, and the teacher gave feedbacks afterwards. Significant difference in the total scores and the scores of term explanation was found between two groups. The results of the questionnaire showed that most of the test group students thought that the electronic concept maps were helpful to promote their understanding and memory. Concept maps reveal the thinking process of human brain, and show the divergent thought. Therefore, concept maps can improve the understanding and the scores in Medical Microbiology studies and are a powerful assistant in Medicine teaching.

Abstract:General biology is the elementary course for biological science in colleges and universities. It contains a mass of contents that involve almost all the subjects of life sciences. Some teaching contents are uninteresting with strong theory, and some contents are already learned from senior high school, which makes the students’ learning interests not very high. They didn’t realize the importance of course learning. To some extent, the quality of biology education was low because of this activity. The Nobel Prize in Physiology or Medicine represents the highest level of life science and medical science and has a significant attraction for the students. By the combination of the Nobel Prize in general biology teaching, including the story of the gainers, progress of investigation, and the design of experiments, it may inspire students’ studying interest, improve students’ understanding and knowledge obtaining, and cultivate students’ creative thinking ability. It will be of great importance in general biology teaching.

Abstract:[Objective] Essential oils are aromatic oily liquids obtained from some aromatic plant materials by distillation and squeezing. In recent years, essential oils have attracted more attention due to their antimicrobial activity. The objective of this study was to analyze the chemical constituents and the antimicrobial activity of essential oils, and the correlation between them. [Methods] Six typical essential oils were selected as experimental target, including cassia oil, litsea cubeba oil, clove oil, citronella oil, rosemary oil and garlic oil. Then the chemical compositions of the above oils were analyzed by GC-MS. Moreover, the antifungal activity against Aspergillus niger and Penicillium funiculosum, and the antibacterial activity against Escherichia coli and Staphylococcus aureus were investigated with poisoned food technique. [Results] GC-MS analyses showed that the chemical composition of cassia oil, litsea cubeba oil, citronella oil, and rosemary oil were all mainly aldehydes and alcohols, the main composition of clove oil was eugenol. Garlic oil was composed of a variety of thio ethers; especially di-2-propenyl trisulfide (allicin) was the highest content in them. The poisoned food technique results revealed that different kinds of essential oil have diffident antimicrobial activities. The antifungal activity order of six essential oils was: cassia oil (highest activity) >garlic oil>clove oil>litsea cubeba oil=citronella oil>rosemary oil, and the antibacterial activity order was: cassia oil (highest activity) >litsea cubeba oil>clove oil>citronella oil=rosemary oil>garlic oil. [Conclusion] The antimicrobial activity of essential oils was closely related to their composition. The high efficient antimicrobial activity of cassia oil, litsea cubeba oil, citronella oil and rosemary oil is possible due to the composition of aldehydes and alcohols; antimicrobial activity of clove oil is result from the composition eugenol; and the high antifungal activity of garlic oils should be related to the composition of thio ethers. The different effective compositions in different essential oils suggest that different oils have different antifungal/antibacterial mechanism.

Abstract:[Objective] Comparing the variability of the maximum specific growth rate, μmax, of 9 different pathogenic and non-pathogenic V. parahaemolyticus strains in TSB (3% NaCl, pH 8.0) at 15 °C, 20 °C and 25 °C. [Methods] An automated turbidimetric system, Bioscreen C, was used to determine the μmax of strains of V. parahaemolyticus. [Results] The coefficient of variation of μmax among 9 V. parahaemolyticus strains was 20.72%, 17.5% and 15.98% at 15 °C, 20 °C and 25 °C, respectively. The variability of μmax among different V. parahaemolyticus strains increased as temperature was decreased. [Conclusion] A quantitative microbial risk assessment of V. parahaemolyticus infection and illness based on the growth characteristics of a single strain of V. parahaemolyticus, introduces a bias in the assessment. It’s necessary to develop stochastic models as the more precise and effective predictive model to be utilized in quantitative microbial risk assessment.

Abstract:

Abstract:[Objective] A strain of bacterium, strain FP6, with the high ability of removing nitrite nitrogen was isolated from the bottom of the shrimp pond, and its phylogeny and denitrifying characteristics were studied. [Methods] Sequence of the 16S rRNA gene, physiological and biochemical properties were analyzed. Factors that affected the denitrifying ability of strain FP6 were investigated, including carbon sources, C/N ratio, initial pH, temperature, shaker speed and NaCl concentration. Moreover, the ability to remove ammonia and nitrate of the strain was also studied. [Results] Among the isolated strains, strain FP6 showed the highest ability to remove nitrite nitrogen and was identified as Bacillus licheniformis. Sucrose was identified as the best carbon source for its growth and denitrification. Under the conditions of C/N ratio 15?25, initial pH 7.0?10.0, temperature 20 °C?37 °C, shaker speed 0?200 r/min and NaCl concentration 0?40 g/L, strain FP6 kept high removing nitrite nitrogen ability. Strain FP6 showed the ability of removing ammonia and nitrate and no nitrite nitrogen was accumulated when removing nitrate. [Conclusion] Strain FP6 possesses excellent removing nitrite nitrogen ability, with wide range of temperature, pH and salinity.

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