Abstract:Abstract: The energy crisis has become one of the major problems hindering the development of the world．The emergence of microbial fuel cells provides a new solution to the energy crisis． Microbial solar cells，integrating photosynthetic organisms such as plants and microalgae into microbial fuel cells，can convert solar energy into electrical energy. Microbial solar cell has steady electric energy，and broad application prospects in wastewater treatment，biodiesel processing and intermediate metabolites production． Here we reviewed recent progress of microbial solar cells from the perspective of the role of photosynthetic organisms in microbial fuel cells，based on a vast amount of literature，and discussed their advantages and deficiency． At last，brief analysis of the facing problems and research needs of microbial fuel cells are undertaken． This work was expected to be beneficial for the application of the microbial solar cells technology.

Abstract:Abstract: Mycobacterium tuberculosis infection kills two million people every year，and the chemotherapy has led to significant amount of drug resistance． Signal transduction systems are used by bacteria to survive or adapt to their living environment，but the relationship to drug resistance is not well understood． In this article，we introduced the twocomponent signal transduction systems of M． tuberculosis and analyzed their relationship with drug resistance． We identified five two-component system pairs involved in the formation of drug resistance． Therefore，these two-component systems are good targeting sites for small biochemical drugs to target so as to reverse the drug resistance and virulence．

Abstract:Abstract:Ochrobactrum anthropi is a gram-negative bacillus，usually known as an opportunistic pathogen． Mostly its infection is related with systemic or local lower immunity，and manifested as bacteremia，meningitis，purulent infection．Recently，along with expanded infection，it has become an important human pathogen．The prevention，clinical diagnose and treatment become complicated because varied clinical symptoms increased antibiotic resistance and cross immune reaction with others pathogens． In this review，we summarized the biological characteristics，differential diagnosis，immunity，resistance and genomic characteristics of Ochrobactrum anthropi，to provide reference for prevention，control and treatment management of this disease．

Abstract:Abstract:Approximately 185 million people are or have been infected with Hepatitis C virus (HCV) worldwide． HCV causes not only severe liver problems but also extra hepatic manifestations，such as insulin resistance (IR) and type 2 diabetes mellitus (T2DM)． Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) is a transcription factor coactivator that plays an essential role in cellular energy metabolism，and cumulative studies link the abnormal high expression of PGC-1α to IR and T2DM． Besides，HCV hijacks host lipid metabolism for its infection，and the very low density lipoprotein (VLDL) secretory pathway is exploited to facilitate HCV assembly and secretion; coincidently，PGC-1α is reportedly important in VLDL assembly through a downstream factor．Therefore，we hypothesize that，on the one hand，HCV infection results in WT-PGC-1α/L-PGC-1α high expression which will further lead to T2DM，on the other hand，WT-PGC-1α and L-PGC-1α demonstrate proviral functions in HCV production through the regulation of VLDL．Combining previous studies in the literature with our current findings，we elaborate the relationship between HCV and PGC-1α，and discuss the mechanism how HCV infection upregulates PGC-1α.

Abstract:Abstract:［Objective］Denitrifying bacteria play an important role in the biological nitrogen removal process．However，there are few studies about hypothermia nitrite denitrifying bacteria．We isolated a hypothermia and aerobic nitritedenitrifying bacterium (named as Y-11) from the long-term flooded paddy soil．Aims of this paper were to clarify the phylogeny and denitrifying characteristics of strain Y-11．［Methods］ Morphological observation，specific phospholipid fatty acid and 16S rＲNA analysis were employed to identify strain Y-11． Denitrification characteristics of strain Y-11，such as temperature，shaking speed，initial pH and carbon source were investigated by using shaking culture in Erlenmeyer flask．［Results］ Strain Y-11 with high removal efficiency of nitrite and total nitrogen was identified as Pseudomonas tolaasii． The optimum conditions of Y-11effectively removing nitrite nitrogen and total nitrogen were: initial pH7.0; 15 ℃; shaking speed 200 r/min; inoculum size 1.5×108 CFU per 100 mL medium; sodium acetate as carbon source; and nitrite nitrogen 10 mg/L．Strain Y-11 can remove nitrite nitrogen and total nitrogen up to 100% and 61.28% within 48 h.［Conclusion］Strain Y-11 was identified as Pseudomonas tolaasii with its potential nitrite polluted water treatment during early winter and late spring．

Abstract:Abstract:［Objective］ We intended to obtain and characterize lactic acid bacteria with high capacity of cholesteroldegrading．［Methods］ We chose Jiangshui as the experimental material，screened lactic acid bacteria by the culture medium with high cholesterol，and studied other features of lactic acid bacteria like salt-tolerant，acid resistance，then identified the species of lactic acid bacteria by combining physiological and biochemical methods and 16S rDNA sequence．［Results］All lactic acid bacteria isolated had the capacity of cholesterol-degrading to some extent．There were 4 strains had high cholesterol-degrading rate (＞75%)．Four strains were Lactococcus lactis subsp． lactis，two were Brevibacterium casei，and one was Lactococcus raffinolactis．［Conclusion］Cholesterol-degrading lactic acid bacteria were screened from Jiangshui，with application potential for cholesterol degradation.

Abstract:Abstract:［Objective］ Rsc1285 is one of the putative T3SS-regulated factors in Ralstonia solanacearum，and the regulation of Rsc1285 on T3SS and pathogenicity was characterized.［Methods］ The rsc1285 deletion mutants were constructed by homologous recombination and characterized by complementation.［Results］ The rsc1285 mutant was significantly less virulent than the wild-type strain to infect tomato plants. Rsc1285 controls the expression of hrpB and HrpB-regulating genes，but it is dispensable for the expression of hrpG and prhG.［Conclusion］R.solanacearum uses Rsc1285 to control the T3SS and pathogenicity via a novel pathway，and this finding provides insights into overall infection mode of R.solanacearum.

Abstract:Abstract:［Objective］Curdlan is produced by Agrobacterium sp．ATCC 31749 under nitrogen limiting condition．The biosynthesis of crudlan is a typical aerobic bioprocess，and the production of curdlan would be severely restricted under micro-aerobic and anoxic conditions．Proteomic analysis of Agrobacterium sp． was conducted to investigate the effect of dissolved oxygen on the crucial enzymes involved in curdlan biosynthesis.［Methods］Two-dimensional gel electrophoresis was performed to separate and visualize the differential expression of the intracellular proteins extracted from Agrobacterium sp．ATCC 31749 cultured under various dissolved oxygen levels (75%，50%，25% and 5%). In addition，a comparative proteomic analysis of the intracellular proteins expression level under various dissolved oxygen levels was done． Significant differently expressed proteins were identified by MALDI-TOF/TOF.［Results］Finally，we identified 15 differently expressed proteins involved in polysaccharide synthesis，fatty acid synthesis，amino acid synthesis pathway．Among these proteins，phosphoglucomutase and orotidine 5-phosphate decarboxylase were the key metabolic enzymes directing curdlan biosynthesis.［Conclusion］Oxygen could affect the expression of the proteins taking charge of curdlan synthesis significantly.

Abstract:Abstract:［Objective］It is of great significance to improve the utilization of lignocellulosic material，the most abundant renewable resource on earth.［Methods］We studied the stress tolerance (temperature，ethanol and osmotic tolerance) of five xylose utilizing yeasts，Scheffersomyces stipitis，Candida tenuis，Spathaspora passalidarum，Candida amazonensis and Candida jeffriesii．We also tested their utilization ability of multiple carbon and nitrogen sources.［Results］ S．passalidarum could tolerate at 44C and utilize various carbon and nitrogen sources effectively. S．passalidarum could metabolism xylose rapidly to produce ethanol，with an ethanol yield of 0.43 g/g under oxygen limiting condition． C．amazonensis could also torelate at 42C．Moreover，C．amazonensis could converse xylose to xylitol with ethanol as the main by-product.［Conclusion］ S．passalidarum is a potentially valuable workhorse in industrial utilization of lignocellulosic for its excellent characteristics． In addition，C．amazonensis may be a promising xylitol producer．

Abstract:Abstract: ［Objective］ To characterize uracil-DNA glycosylase from acidophilic and thermophilic Sulfolobus acidocaldarius.［Methods］We cloned udgIV and udgV genes from S.acidocaldarius，expressed the two recombinant UDG proteins in E.coli species BL21 (DE3) Rosetta-pLysS，purified the recombinant UDGs and characterized the removal of dU by UDGs.［Results］We successfully expressed two S.acidocaldarius UDGs and found both UDGs having the activity of dU removal. In comparison to UDGV，UDGIV was more efficient in dU removal，with a 750-foldactivity.［Conclusion］In comparison to UDGV，UDGIV from S． acidocaldarius was a more efficient enzyme responsible for the removal of dU from DNA in vitro.

Abstract:Abstract:［Objective］The endoglucanase from Fusarium sp.Q7-31T was isolated，purified，identified and characterized to provide data for enzyme system of Fusarium sp.［Methods］Strain was cultured in liquid fermentation with oat strawas carbon source，the endoglucanase was purified by using Sephacry S-100 chromatography and DEAE-sepharose ionexchange column chromatography and the enzymatic properties were studied．The protein was identified using MADILTOF-TOF.［Results］ An endoglucanase was purified and named Egn20． The molecular weight was 55.37 kDa and isoelectric point (pI) was 7.44． Egn20 had optimal activity with carboxymethyl cellulose at 40 ℃ and pH6. 0，stabilized at 45 ℃ and pH5.0－7.0，activated by Fe2+，inhibited by Na+，Ca2+，Mg2+，Zn2+，K + and inactivated by Hg2+．The enzymatic properties and MADIL-TOF-TOF results suggested that Egn20 belongs to GH7 family.［Conclusion］ Our results may provide important data for the study of Fusarium sp．enzyme system.

Abstract:Abstract:［Objective］The aim of this study was to analyze the bacterial diversity of urban section of Nanming river as well as to study relationship between the bacterial diversity and environmental factors.［Methods］The high throughput sequencing on PCR-amplified 16S rDNA V4 fragments was used to determine the bacterial diversity of samples from five sites of Nanming river．The ordination technique of redundancy analysis was used to analyze the effects of the environmental factors on bacterial community composition.［Results］ Diversity index analysis of bacterial community composition in Nanming river showed that the Shannon-Wiener index of bacterial diversity in Nanmng River was about 7.5．The Shannon-Wiener index of 5 sampling site had an order as Wudang bridge＞Shuikou Si＞Wuyan bridge＞Huaxi bridge＞Guanzhou bridge．Based on the sequencing results，there were 11 phyla (327 genera) in the samples，of which proteobacterice (66.1%±3.30%) was the dominant phyla，Gamma proteobacteria (54.76%±4.86%) was the dominant subgroup and Pseudomonas (16.92%±0.02%) was the dominant genera．In addition，there are some flora and rare flora undetermined． The result of RDA suggested that the influence of different environmental factors on different microbes were different． Bacterial community Ⅳ had significant positive correlation with total nitrogen and total phosphorus in the environment.［Conclusion］This research provides references for the association of bacterial composition and diversity with environmental factors.

Abstract:Abstract:［Objective］This study was aimed to improve the thermal stability of carboxylesterase from Geobacillus sp．ZH1 by directed evolution.［Methods］ A library of carboxylesterase mutants was constructed by introducing random mutagenesis using error-prone PCR to screen mutant enzymes with improved thermostability．After induction，expression and purification，the mutant enzyme was characterized.［Results］After screening，one mutant strain 65 was obtained with improved carboxylesterase thermal stability． Sequence analysis revealed two amino acid substitutions，including T113S and M160K． According to homologous modeling，T113S was located on the fifth β-sheet. Another mutant site M160K was located on a loop between the fifth and the sixth α-helix，being on the surface of the mutant enzyme． The mutated Lys160 formed an extra hydrogen bond with nearby Thr162． The half-life of mutant enzyme 65 and the parent enzyme at 90 ℃ was 3.1 h and 1.9 h，respectively． The mutant enzyme 65 had a better thermal stability than the parent enzyme.［Conclusion］Directed evolution by error-prone PCR of Geobacillus sp． ZH1 carboxylesterase gene is effective to improve the thermal stability.

Abstract:Abstract:［Objective］To observe cell membrane and nucleus in bacteria for subcellular localization.［Methods］FM4-64 and Hoechst were dyed that can label cell membrane and nucleus，respectively． Both dyes were used to co-stain the membranes and nucleus of eight bacterial strains ( Escherichia coli，Staphylococcus aureus，Pseudomonas aeruginosa，Klebsiella pneumoniae，Yersinia pestis，Legionella pneumonia，Vibrio cholerae and Bacillus anthracis)． E.coli was dyed with different dye concentrations and times and then observed by confocal fluorescence microscopic imaging.［Results］Fluorescence intensity of cell membrane and nucleus is affected by dye concentrations and times． The optimal conditions were determined as follows: staining cell membrane with 20 μg/mL FM4-64 for 1 min and cell nucleus with 20 μg/mL Hoechst for 20 min．Gram-negative bacteria were dyed better than gram-positive bacteria with FM4-64dye．［Conclusion］FM4-64 and Hoechst can be used to stain membrane and nucleus in different types of bacteria．Co-staining bacterial membrane and nucleus provides the reference to observe cell structure in prokaryotes for studying subcellular localization．

Abstract:Abstract:［Objective］ We used Shewallena oneidensis MR-1 to produce selemium (Se) nanobars and studied the influence of Se(IV) concentrations and incubation time on nanobars production.［Methods］We incubated Shewallena oneidensis MR-1 under anaerobic condition with Luria-Bertani (LB) liquid medium containing 0.1，1.0，10.0 or 100.0 mmol/L Se(IV) in Na2 SeO3，to determine the optimal Se(IV) concentration for bacterial growth．Then，we incubated Shewallena oneidensis MR-1 with the optimal Se (IV) concentration and collected deposits 24 and 72 h after anearobic incubation．We used scanning electron microscopy，energy-dispersive X-ray and X-ray diffraction to analyse the deposits.［Results］The cross sectional diameter and length of deposits that were produced by Shewallena oneidensis MR-1 after 24 h incubation with 1 mmol/L Se(IV) was around 80 nm and 2-3 μm，respectively． However，the deposits after 72 h incubation exceeded the size limit of nano material． Furthermore，the energy-dispersive X-ray and the X-ray diffraction spectroscopy confirmed that the deposits were elemental Se.［Conclusion］This study provides a viable method for the biosynthesis of Se nanobar. Shewallena oneidensis MR-1 can produce a large number of Se nanobars at exponential phase under 0.1 mmol /L Se(IV).