Abstract:Abstract:Polycyclic aromatic hydrocarbons (PAHs) are a recalcitrant group of contaminants in the environment．PAHs degradation has been extensively studied and well understood under aerobic conditions，whereas little is known about anaerobic degradation of PAHs． Here，we reviewed recent progress in anaerobic degradation of PAHs． We focused on naphthalene and phenanthrene as model compounds． We addressed the main rate-limiting factors involved，including the bioaccessibility of PAHs，the amendment of nutrients and elector acceptors，the degrading microorganisms，and the biochemistry of the initial activation and subsequent enzyme reaction involved in the pathway． Prospects on this field are also discussed．

Abstract:Abstract: Co-culturing Bacillus megaterium and Ketogulonigenium vulgare is widely applied to 2-keto-gulonic acid production． For optimizing the process，numerous researchers studied on the symbiotic molecular mechanism of the coculture process． The research was promoted greatly owing to omics technologies，bioinformatics，high throughput technologies and physiology． Recently，the proteomic，metabolomic，comparative genomics and transcriptomics were performed to the research． These omics data provided us the interaction network of the artificial ecosystem in multilevel．Combining with the physiological validation based on the high throughput method，we can elucidate the molecular mechanism in detail，which will facilitate us to develop strategies for metabolic engineering． The paper reviewed the recent developments of symbiotic molecular mechanism research in this co-culture process and its applications． In addition，we propose the future research needs.

Abstract:Abstract:Entomopathogenic fungi as potential agents for bio-control have been widely applied in the control of insect pests in agriculture． However，the application remains in laboratory scale for the control of ectoparasites．Owing to the need to combat the short lasting period of chemical acaricides and reduction of pollution，it is urgent to develop sufficient，stable and safe measures for tick control． We reviewed the primary scientific achievements in utilization of environmental microbes for controlling of ticks．Studies conducted in this field may benefit to sustainable development，environmental protection，maintaining ecological balance and production of green products．

Abstract:Abstract:［Objective］ Vibrio parahaemolyticus causes acute gastroenteritis by secreting a number of virulence factors including two sets of type VI secretion systems (T6SS1 and T6SS2)．However，it remains unknown how T6SS is regulated in the bacterium and what kinds of effects the systems have on adhesion onto and invasion into the host cells． This study was attempted to examine if VPA1045 and VPA1049 regulate T6SS2．［Methods］Vpa1045 and Vpa1049 deletion mutants were constructed by homologous recombination． Real-time PCR was performed to examine the transcription level of the translocon protein gene hcp2 in V．parahaemolyticus clinical strain HZ and its mutants． Western blot was used to analyze the levels of expression and translocation of Hcp2．［Results］Both VPA1045 and VPA1049 contain the Che-Y domain，and belong to the two-component regulators． Deletion of either Vpa1045 or Vpa1049 did not affect expression and transcription of Hcp2，but decreased translocation of Hcp2 in the supernatant of V． parahaemolycus． Bacterial adherence to the HeLa monolayers was also significantly reduced as compared with their parent strains．［Conclusion］ The twocomponent regulators VPA1045 and VPA1049 regulate T6SS2 of V． parahaemolyticus post-translationally by up-regulating Hcp2 translocation．

Abstract:Abstract:［Objective］Expression and subcellular location of NSm protein of Tomato spotted wilt virus were studied using plant and insect cells． ［Methods］First，the NSm gene，located on the ambisense M RNA segment of tomato spotted wilt virus，was cloned into the pCHF3 vector which includes a GFP gene． Agrobacterium-mediated transient expression from N．benthamiana leaves was used to study the location of NSm in plant cells． Second，to test whether plant-specific components were involved in tubule formation，the NSm gene was also expressed in a heterologous expression system，i.e.，insect cells. T. ni (Tn) cells were infected with a recombinant baculovirus expressing the NSm gene．［Results］NSm-GFP fusion proteins diffused in the tobacco epidermal cells and were located at the edge of the cell walls． These proteins can also form discontinuous green fluorescent spots at the plasmodesmata，which were sometimes present in pairs between two neighboring cells． However，GFP proteins expressed alone distributed evenly around the cell wall and in the nucleus． In the entomic Tn cells，NSm proteins formed a large number of tubular structures extending from the surface．Conclusion］These findings suggest that NSm protein target the plasmodesmata specifically in plant cells，and they also could form tubular structures on the surface when expressed in entomic Tn cells．

Abstract:Abstract:［Objective］ Elucidating the correlation between the secondary structure of the leader peptide of lantibiotic bovicin HJ50 and its modification and processing．［Methods］The variants with mutated leader peptide were synthesized by semi-in vitro biosynthesis，and their modification pattern were then analyzed by MALDI-TOF MS．At the same time，the effect of leader peptide mutants on processing the modified propeptide was examined by HPLC and antimicrobial activity．［Results］ We constructed 6 mutants (F-16A，V-15E，E-14L，E-8P，L-7D，L-4K) involved in forming secondary structure of the bovicin HJ50 leader peptide． F-16A，V-15E，L-4K showed very little effect on modification and processing whereas E-14L and E-8P caused changes in modification． In addition，we found that L-7D strongly affected the processing．［Conclusion］The conserved helix structure in the leader peptide of bovicin HJ50 was closely related to the activity of BovM and BovT150，and the presence of secondary structure was very important to modification and processing of bovicin HJ50．

Abstract:Abstract:［Objective］To study the bacterial community change during the phase II composting of Volvariella volvacea substrate of cotton waste and to clarify the predominant bacteria at different composting stages． Methods］ The 16S rDNA-DGGE (denaturing gradient gel electrophoresis) and clone strains sequencing methods were used to track the change of bacterial community during composting．［Results］ The DGGE profile shows that the diversity of bacterial community was rich and bands diversity decreased with the composting progress． The dynamic changes of predominant community and relative intensity were observed． The 23 predominant strains belong to 3 classes of Proteobacteria，Bacteroidetes and Firmicutes，6 families of α，β，γ-Proteobacterium，Bacteroidetes，Sphingobacteria and Clostridia，11 genera，in which 19 strains were thermophilic bacteria． The genera of Stenotrophomonas，Comamonas，Sphingobacterium and Sinorhizobium were predominant bacteria in the stages of high temperature and drop of temperature during composting．［Conclusion］The bacterial community structure and predominant community change dynamically during the phase II of Volvariella volvacea composting，especially in the course of entering the stage of high temperature．

Abstract:Abstract:［Objective］To identify the relationship between salicylate 5-hydroxylase activity and the degradation rate of phenanthrene by moderately halophilic Martelella sp． AD-3， and to investigate their enzymatic characteristics．［Methods］ The products resulted from degradation of salicylic acid using the crude enzyme produced by AD-3 was analyzed using HPLC analysis，and salicylate 5-hydroxylase activities at different conditions was calculated according to the change of NADH absorbance at 340 nm． ［Results］The salicylate 5-hydroxylase activity was higher during log-phase and early stationary phase of AD-3，and the enzyme activity was in consistent with phenanthrene degradation rate． The enzyme production was induced by phenanthrene and salicylic acid． The highest enzyme activity，132.8 nmol/(min·mg)，from strain AD-3 was obtained under the phenanthrene concentration of 200 mg/L，3% salinity and a pH of 9.0．The optimum conditions for degradation of salicylic acid using this enzyme were 30℃，pH 7.5，and salinity 3%．The Vmax and Km for the enzyme were 200 nmol/(min·mg) and 8.7μmol/L，respectively．［Conclusion］The salicylate 5-hydroxylase was produced in the degradation of phenanthrene in AD-3． The enzyme activity was related to phenanthrene degradation rate．

Abstract:Abstract:［Objective］To cultivate various yet-to-be cultured heterotrophs from anaerobic granule sludge，we used a selective culture medium with low concentrations of substrates supplemented a variety of antibiotics.［Methods］An obligate anaerobic，thermophilic，hydrogen-producing bacterium，strainVM20-7T，was isolated from an upflow anaerobic sludge blanket ( UASB) reactor treating high-strength organic wastewater from isomerized sugar production processes．［Results］Cells of strain VM20-7T are non-motile，spherical，pear or teardrop shaped，occurring singlyo r as aggregates (0.7－2.0μm×0.7－2.0μm)．Spore formation was not observed． Growth temperature ranges from 35－50℃ (optimum 45℃)，pH ranges from 6.0－8.3 (optimum 7.0－7.5)，NaCl tolerant concentration ranges from 0%－0.5% (w/v，optimum 0%)．Nitrate，sulfate，thiosulfate，sulfite，elemental sulfur and Fe (III)-NTA were not used as terminal electron acceptors． Strain VM20-7T utilizes a wide range of carbohydrates，including glucose，maltose，ribose，xylose， sucrose，galactose，mannose，raffinose，pectin，yeast extract and xylan． Acetate and H2 are the main end products of glucose fermentation． The G+C content of the genomic DNA was 60.9 mol%．16S rRNA gene sequence analysis revealed that it is related to the Pirellula-Rhodopirellula-Blastopirellula ( PRB) clade within the order Planctomycetales (82.7－84.3% similarity with 16S rRNA genes of other known related species)．［Conclusion］ The first obligate anaerobic bacterium within the phylum Planctomycetes was isolated with low concentration of carbohydrates and antibiotics．On the basis of the physiological and phylogenetic data，the name Thermopirellula anaerolimosa gen．nov.，sp. nov．is proposed for strain VM20-7T (= CGMCC 1. 5169T = JCM 17478T = DSM 24165T)．

Abstract:Abstract:［Objective］The purpose of this study is to examine the relation between the sex ratio of Ericerus pela and its symbiotic bacterial Arsenophonus． ［Methods］ The symbiotic bacterial diversity in male Ericerus pela was determined through sequencing 16S rDNA gene library． PCR amplification for Arsenophonus was performed by using two 16S rDNA specific primers and 23S rDNA specific primer． The molecular detection of Arsenophonus in six geographic populations of E． pela，namely Zhaotong，Kunming，Jinkouhe，Hangzhou，Changchun，and Jianghua，were performed by semiquantitative PCR． The absolute concentrations of Arsenophonus in E． pela of Zhaotong，Kunming，Jinkouhe geographic populations were determined using absolute quantitative real-time PCR． ［Results］ Two different 16S rDNA sequences were obtained; the sizes were 445bp and 1462bp respectively． A 23S rDNA sequence was obtained，the size was 582bp．Some E． pela individuals of Hangzhou and Jianghua were not infected with Arsenophonus． The contents of Arsenophonus in E． pela of Zhaotong were significantly higher than that of Kunming and Jinkouhe，while the contents of Arsenophonus from the latter two geographic populations were not significantly different． ［Conclusion］Arsenophonus is not responsible for the sex ratio of E．pela．

Abstract:Abstract:［Objective］To detect the diversity of the degradation bacteria of halogenated-alkane form the surface seawater of the Arctic Ocean． ［Method］Twelve surface-water samples from the Arctic Ocean were collected and enriched using C16 H33 Cl as the sole carbon and energy source． Bacteria from the enriched cultures were isolated on marine agar，and followed by 16S rRNA gene identification and phylogenetic analysis． Further，their degradation ability was tested with C16 H33 Cl． The bacterial community structures were further examined by denaturing gradient gel electrophoresis (DGGE)．［Result］In total 112 isolates were obtained from the 12 samples，of which 19 isolates degraded C16 H33 Cl． Bacteria of Alcanivorax and Rhodococcus exerted good emulsification and degradation，whereas bacteria of Marinobacter also had the degradation capacity，but less． DGGE analysis revealed that Alcanivorax，Parvibaculum and Thioclavawere dominated in the enriched consortia．［Conclusion］ The C16 H33 Cl degradation bacteria in the Arctic marine environment mainly belonged to α-proteobacteria，γ-proteobacteria，actinobacteria and bacteroidetes．This is the first report on the diversity of degradation bacteria of halogenated alkane in the Arctic Ocean． Our result contributed to the knowledge about the arctic environment and the biodiversity of degrading bacteria.

Abstract:Abstract:［Objective］To investigate the contribution of an outer membrane protein OmpW to tolerance neomycinsulphate and ampicillin of Escherichia coli K12. ［Methods］The ompW knock-out mutant (ΔompW) of E． coli K12 was generated using λ-Red recombination system． Then the minimal inhibitory concentration (MIC) and the survival rates under 1/2 MIC of neomycinsulphate or ampicillin of ΔompW and E． coli K12 were determined respectively． ［Results］The ΔompW was successfully obtained through confirmation of PCR analysis at the gene level and Western blot analysis at the protein level． The MIC of neomycinsulphate of ΔompW is 1.7 μg/mL．The value is much lower than that of E． coli K12，which is 8.0μg/mL． Difference of survival rates under 1 /2 MIC of neomycinsulphate of ΔompW and E． coli K12 was also observed，and their survival rates are 39% and 98% ，respectively． The MIC of ampicillin of ΔompW is 3.3 μg/mL．The value is also lower than that of E． coli K12 (16.0μg/mL)．The survival rates under 1/2 MIC ampicillin of ΔompW and E．coli K12 are 30.3% and 70.38%， respectively．［Conclusion］ The ΔompW is much more sensitive to neomycinsulphate and ampicillin than its parent strain． The result indicated that OmpW played crucial role in bacteria resistance of drug．

Abstract:Abstract:［Objective］The aim of the study was to understand the mechanism of Cytophaga hutchinsonii adhension to cellulose．［Methods］ The effects of different factors on the bacterial adhesion to cellulose were studied，including bacterial age，pH，temperature，cell surface charge，cell viability，cell surface protein，extracellular polysaccharides，and cellulose derivates．［Results］Treatments with heat and protease reduced the adhesion remarkably． But treatments with NaN3，formalin，glutaraldehyde，Congo red and NaIO4 had only slight effect on the adhesion． The adhension of Cytophaga hutchinsonii cells to microcrystalline cellulose was specific and not inhibited by cellobiose or carboxymethyl cellulose．［Conclusion］The adhesion of Cytophaga hutchinsonii to cellulose was closely related to cell surface proteins，while cellular metabolic activity and extracellular polysaccharides had only slight effect on it． It is speculated that there might be some specific cellulose binding proteins on the cell surface．

Abstract:Abstract:［Objective］This paper provides an overview of Desulfovibrio (DSV) incidence and its effect on bacterial diversity in human gastrointestinal tract of four groups: ulcerative colitis (UC)，colorectal cancer (CRC)，polypus (PP) and the healthy control (H)．［Methods］ Real time fluorescence quantitative PCR (RT-PCR) assays were used to enumerate DSV in gastrointestinal tract of 58 subjects． Diversity of gut microbiota was analyzed by PCR-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) and 16S rRNA V3 sequencing．［Results］ RT-PCR detected DSV in all samples． Significantly increased numbers of DSV were observed for UC and PP groups compared with CRC and H groups．No significant difference was observed for CRC and H groups with gene copy numbers of DSV． Alterations of DSV and gut microbiota were observed in disease groups． ［Conclusion］ We found that quantity and diversity of DSV are significantly increased in UC and PP compared to controls． The increased numbers of DSV in disease groups suggests a possible harmful role．

Abstract:Abstract:［Objective］We studied the biological function of Brucella phosphoglucomutase (pgm) gene，and detected the changes of human trophoblast cell invaded by the Brucella pgm mutant and PGM protein．［Methods］Human trophoblast cells were infected by the pgm mutant and PGM protein． The changes of cytokines were detected by enzyme-linked immunosorbent assay，and morphology of cells was identified．［Results］PGM protein was purified，and pgm mutant was constructed．The sera of mice immunized by pgm mutant were negative by agglutination test and Standard Tube Agglutination Test for Brucellosis． The cellular morphology of human trophoblast cells infected pgm mutant or PGM protein changed． The adhesion and infection of the pgm mutant reduced more than Brucella vaccine strain M5-90，and human trophoblast cells partially cracked off． The activity of IL-6，TNF-α or lactic dehydrogenae increased in human trophoblast cells infected by the pgm mutant more than Brucella vaccine strain M5-90 (P＜0.01)，but not for IL-10. Lactic dehydrogenae in human trophoblast cells infected by the PGM Protein increased more than sodium phosphate buffer (P＜0.01)，whereas IL-6 and TNF-α decreased in human trophoblast cells less than sodium phosphate buffer (P＜0.05)．［Conclusion］The results suggest that the pgm mutant of brucella and PGM protein had the cytotoxic effect for human trophoblast cells with cellular morphology and changes of cytokines．