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Tetrachloroethylene （PCE） and trichloroethylene （TCE） are typical volatile halogenated organic compounds in groundwater that pose serious threats to the ecological environment and human health. To obtain an anaerobic microbial consortium capable of efficiently dechlorinating PCE and TCE to a non-toxic end product and to explore its potential in treating contaminated groundwater， an anaerobic microbial consortium W-1 that completely dechlorinated PCE and TCE to ethylene was obtained by repeatedly feeding PCE or TCE into the contaminated groundwater collected from an industrial site. The dechlorination rates of PCE and TCE were （120.1 ±4.9） μmol·（L·d） -1 and （172.4 ±21.8） μmol·（L·d） -1 in W-1， respectively. 16S rRNA gene amplicon sequencing and quantitative PCR （qPCR） showed that the relative abundance of Dehalobacter increased from 1.9% to 57.1%， with the gene copy number increasing by 1.7×10 7 copies per 1 μmol Cl - released when 98.3 μmol of PCE was dechlorinated to cis -1，2-dichloroethylene （ cis -1，2-DCE）. The relative abundance of Dehalococcoides increased from 1.1% to 53.8% when cis -1，2-DCE was reductively dechlorinated to ethylene. The growth yield of Dehalococcoides gene copy number increased by 1.7×10 8 copies per 1 μmol Cl - released for the complete reductive dechlorination of PCE to ethylene. The results indicated that Dehalobacter and Dehalococcoides cooperated to completely detoxify PCE. When TCE was used as the only electron acceptor， the relative abundance of Dehalococcoides increased from （29.1 ±2.4）% to （7.7 ±0.2）%， and gene copy number increased by （1.9 ±0.4）×10 8 copies per 1 μmol Cl - released， after dechlorinating 222.8 μmol of TCE to ethylene. The 16S rRNA gene sequence of Dehalococcoides LWT1， the main functional dehalogenating bacterium in enrichment culture W-1， was obtained using PCR and Sanger sequencing， and it showed 100% similarity with the 16S rRNA gene sequence of D. mccartyi strain 195. The anaerobic microbial consortium W-1 was also bioaugmented into the groundwater contaminated by TCE at a concentration of 418.7 μmol·L -1 . The results showed that （69.2 ±9.8）% of TCE could be completely detoxified to ethylene within 28 days with a dechlorination rate of （10.3 ±1.5） μmol·（L·d） -1 . This study can provide the microbial resource and theoretical guidance for the anaerobic microbial remediation in PCE or TCE-contaminated groundwater.

We studied the effects of the lidocaine on the hERG K(+) channels with a focus on the electrophysiology of the heart. The hERG current was recorded using the conventional whole-cell patch clamp technique and the channel protein expression level was measured with Western blot in HEK 293 cells stablely expressed hERG K(+) channels. The langendorff perfusion system was used to record the ECG from isolated rabbit heart. Lidocaine inhibited hERG current in a concentration-dependent manner at 0.3-1 000 μmol·L(-1), the IC(50) value was 88.63 ±7.99 μmol·L(-1). The inhibitory action was enhanced by positive votalge without changing the votalge-dependent activation of the channel. However, lidocaine inhibited hERG current in a frequency-dependent manner. In addition, chronic incubation of lidocaine did not change the hERG K(+) channel protein expression. ECG recordings in the isolated perfused rabbit heart demonstrated that lidocaine( > 100 μmol·L(-1)) did not affected QTc interval, but decreased the heart rate and prolonged the PR interval and QRS duration. Our results demonstrate that lidocaine potentially inhibits the hERG K(+) current at a high concentration, but does not prolonged the QTc of ECG.

The challenge of the emergence of drug-resistant influenza strains, which is caused by wide spread utilization of direct-acting antivirals (DAAs), accelerates the research and exploration towards host targeted agents. In contrast to DAAs targeting viral replication components, host targeted agents, which regulate host factors and pathways linked to viral replication, can interfere the replication of influenza. Additionally, the innate immune system is activated by influenza during the early stage of infection, so manipulating the innate immune response may prevent the viral infection. However, the excessive inflammatory response induced at the late phase of influenza infection would lead to severe tissue injures. Thus, it is very important to explore drugs with anti-inflammatory actions to suppress these immune imbalances and tissue injures. Here we overview the current progresses about host targets related to anti-influenza drugs.

This study is to investigate the effect of recombinant human interferon alpha 2b against broad-spectrum respiratory viruses in vitro. At the cellular level, the effect of the recombinant human interferon alpha 2b on influenza A virus was detected using real-time fluorescence quantitative RT-PCR. The effects of the recombinant human interferon alpha 2b on influenza B virus, parainfluenza virus, respiratory syncytial virus (RSV) and coronavirus were detected using cytopathic effect (CPE) method. In this study, the therapeutic index of recombinant human interferon alpha 2b anti-HPIV was 1476.63, the therapeutic index of recombinant human interferon alpha 2b anti-RSV was 141.37, the therapeutic index of recombinant human interferon alpha 2b anti-coronavirus was more than 2820.76, and the antiviral effect of recombinant human interferon alpha 2b was better than ribavirin (RBV). Recombinant human interferon alpha 2b has a stronger inhibitory effect on different influenza A virus RNA than drug control. The therapeutic index of recombinant human interferon alpha 2b anti-influenza B virus was 2.74, with modest effect. Recombinant human interferon alpha 2b in vitro has broad spectrum antiviral activities, low toxicity and high therapeutic index. Recombinant human interferon alpha 2b is expected to become the efficient medicine in clinical against respiratory viruses, as well as provide better services for prevention and treatment of respiratory viruses' infections.

APOBEC3 is a class of cytidine deaminase, which is considered as a new member of the innate immune system, and APOBEC3G belongs to this family. The research about APOBEC3G is a new direction of innate immune defense mechanism against virus. APOBEC3G has the restrictive activity on many viral replications, which deaminates dC to dU in the viral genome and then induces extensive hypermutation. APOBEC3G can also interrupt viral replication at several phases such as reverse transcription, replication, nucleocapsid and so on by non-deamination mechanisms. However, virus can encode viral proteins to counteract the restriction activity of APOBEC3G. Elucidation of the antagonistic interaction between APOBEC3G and the virus will be contributed to development of new antiviral drugs in the future.

Thirty-three compounds were isolated from the root decoction of Isatis indigotica by using a combination of various chromatographic techniques including silica gel, macroporous adsorbent resin, Sephadex LH-20, and reversed-phase HPLC. Their structures were elucidated by spectroscopic data as (+)-dehydrovomifoliol (1), (S)-(+)-abscisic acid (2), vomifoliol (3), cyclo (L-Phe-L-Leu) (4), cyclo(L-Phe-L-Tyr) (5), cyclo(L-Tyr-L-Leu) (6), cyclo(L-Pro-L-Tyr) (7), evofolin B (8), (+)-syringaresinol (9), (-)-(7R,7'R,8S,8'S)-4,4'-dihydroxy-3-methoxy-7,9';7',9-diepoxy-lignan (10), (-)-medioresinol (11), (+) -(7R,7'R,8S,8'S) -neo-olivil (12), (-) -5-methoxyisolariciresinol (13), 1,3-dihydro-2H-indol-2-one (14), isalexin (15), dihydroneoascorbigen (16), indican (17), (-) -(S) -cyanomethyl-3-hydroxyoxindole (18), isoformononetein (19), calycosin (20), stigamast-5-ene-3beta-ol-7-one (21), acetovanillone (22), 3, 5-dimethoxy-4-hydroxyacetophenone (23), dihydroconiferyl alcohol (24), dihyroferulic acid (25), 3-hydroxy-1-(4-hydroxyphenyl) propan-1-one (26), beta-hydroxypropiovanillone (27), 4-aminobenzoic acid (28), 3-(4-hydroxyphenyl) propan-1-ol (29), 4-(2-hydroxyethyl) phenol (30), 2-methoxy-4-vinylphenol (31), pyrocatechol (32), and 4-pentenamide (33). These compounds were isolated from the root of I. indigotica for the first time. In preliminary in vitro assays, compound 19 showed activity against the influenza virus A/Hanfang/359/95 (H3N2), the herpes simplex virus 1 (HSV-1), and Coxsackie virus B3 (Cox-B3), with IC50 values of 2.06, 6.84, and 8.70 micromol x L(-1), respectively, but other compounds were in-active at a concentration of 1.0 x 10 x (-5) mol x L(-1).

Animal model is very important for anti-EV71 (enterovirus 71) drug and vaccine development. 1-day-old suckling EV71 mouse model is the main in vivo model used in China. 1-day-old suckling EV71 mouse is too small to perform antiviral experiment. And the route of administration and dosage capacity are also restricted. A strong virulence EV71 virus strain was selected after screening from five EV71 strains with 1-day-old suckling mice. A mouse-adapted EV71 strain with increased virulence in 12-day-old suckling mice, EV71-M5, was generated after five serial passages of the parental EV71 strain in mice. Virus titers of EV71 infected mice heart, liver, spleen, lung, kidney, small intestine, brain and muscle tissue were determined by cytopathic effect (CPE) assay. The virus used in this model is the first isolated EV71 strain in China. And 2-week-old suckling mice were used in this model. This is a supplement for the EV71 animal model in China. Establishment of this EV71 model will provide an attractive platform for anti-EV71 vaccine and drug development.

Aminoglycoside antibiotics, due to their strong antibacterial effects and broad antimicrobial spectra, have been very commonly used in clinical practice in the past half century. However, aminoglycoside antibiotics manifest severe ototoxicity and nephrotoxicity, and are one of top factors in hearing loss. In this study, three members of the aminoglycoside antibiotics family, gentamycin, neomycin and streptomycin, were chosen as the representatives to be investigated for their toxicity to the embryonic development and the larva hair cells in zebrafish, and also to their target genes associated with hearing-related genes. The results showed that: (1) the lethal effect of all three drugs demonstrated a significant dependence on concentration, and the severity order of the lethal effect was streptomycin > neomycin > gentamycin; (2) all the three drugs caused the larva trunk bending in resting state at 5 dpf (day past fertilization), probably due to their ototoxicity in the physical imbalance and postural abnormalities; (3) impairment and reducing of the hair cells were observed in all three cases of drug treatment; (4) four genes, eya1, val, otx2 and dlx6a, which play an important role in the development of hearing organs, showed differential and significant decrease of gene expression in a drug concentration-dependent manner. This study for the first time reports the relevance between the expression of hearing genes and the three ototoxic antibiotics and also proved the feasibility of establishing a simple, accurate, intuitive and fast model with zebrafish for the detection of drug ototoxicity.

In order to find antiviral compounds with novel structures, geldanamycin and lamivudine with different antiviral mechanisms were conjunctively synthesized to acquire a new compound TC-GM, and the antiviral activity of TC-GM was measured. The antiviral activity against HIV-1 was examined by p24 antigen ELISA kit. The activity against HBV was examined by dotblot. The activity against HSV and CoxB virus was examined by CPE. TC-GM exhibited broad-spectrum antiviral activities similarly like geldanamycin. TC-GM inhibited the replication of different viruses, including HIV-1, HBV, HSV 1 and 2, CoxB6. TC-GM showed more potent inhibitory activity against HIV-1 and HBV than other detected virus.

Scavenger receptor CD36 could bind and endocytose oxLDL into macrophages which were then differentiated into foam cells that constitute the atherosclerotic lesion core, and was considered to be a potential target to treat atherosclerosis. In the establishment of the compound library of berberine (BBR, 1) analogues, we discovered that 13-hexylberberine (2) showed an antagonistic activity against CD36. Taking 2 as the lead compound, 21 derivatives were synthesized and their antagonistic activities were evaluated via an ELISA-like high-throughput screening (HTS) model. The primary structure-activity relationships were studied. It was indicated that the introduction of suitable groups at the 2- and 3-position of the aromatic ring A or at the 9-position of the aromatic ring D could enhance the activity. Among the 21 studied compounds, 7g bearing a benzyloxyl group at the 9-position provided a highest CD36 antagonistic activity with the IC50 value of 7.7 micromol L(-1). Besides, its antagonistic activity was further verified with Sf9 insect cell HTS model. So berberine analogues are a new family of CD36 receptor antagonists and worthy to be studied further.

Liver cancer is one of the most common neoplastic diseases with high mortality in China. Currently, antimicrotubule drugs such as paclitaxel (PTX) and vincristine (VCR), are used as the common agents in the clinical chemotherapy for liver cancer. However, the responses of patients to these drugs vary markedly. Successful identification of intracellular factors influencing liver cancer's sensitivity to antimicrotubule drugs would be of great clinical importance. In this study, by engineering human hepatoma cell HepG2 to overexpress synuclein-gamma (SNCG), we investigated if SNCG is a molecular factor associated with the sensitivity to antimicrotubule drug treatment. Real-time RT-PCR and Western blotting assays showed SNCG was successfully overexpressed in HepG2/ SNCG cells compared with HepG2/Neo cells. The overexpressed SNCG altered the proliferation activity in HepG2 cells, which was 66% higher than that of HepG2/Neo cells through MTT method. The overexpressed SNCG also reduced sensitivity of HepG2 cells to antimicrotubule drugs: after PTX or VCR treatment, the proportion of HepG2/SNCG cells in G2/M arrest was significantly lower than that in HepG2/Neo cells. Correspondingly, HepG2/SNCG cells showed significantly lower mitotic index than HepG2/Neo cells. Meanwhile, HepG2/SNCG cells showed higher resistance to PTX and VCR than HepG2/Neo cells, with resistance index 21 and 15 respectively. Our studies suggested that the overexpression of SNCG could confer resistance to antimicrotubule drugs in hepatoma cells; and it indicated that SNCG may be as a potential response marker for antimicrotubule drugs in liver cancer chemotherapy.

Ten pharmacophore models of beta-tubulin inhibitors were established from the training set of seventeen beta-tubulin inhibitors (two categories) with comformer analysis by using the Catalyst software. The optimal pharmacophore model with two hydrophobic units and two hydrogen bond acceptor units were confirmed (RMS = 0.43, Correl = 0.98, Weight = 2.06, Config = 15.97). This pharmacophore model is able to predict the activity of known beta-tubulin inhibitors and can be further used to identify structurally diverse compounds with higher activity.

Influenza virus is a virus causing upper respiratory tract infection disease with high morbidity and mortality. China is considered as an area with high rate of influenza morbidity. Prevention and treatment of influenza currently rely on vaccines and antiviral agents in the world. In addition, traditional Chinese medicines also have been used in clinical for influenza therapy. In vitro anti-influenza virus activities of 10 traditional Chinese medicines were studied by cytopathic effect (CPE). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Guangdong Luohu/219/2006 (H1N1); Yinhuang oral liquid had strong antiviral activity against influenza virus A/Hanfang/359/95 and A/Yuefang/243/72 (H3N2). Qingkailing oral liquid (factory G) had strong antiviral activity against influenza virus A/Jifang/15/90 (H3N2). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Jifang/15/90, A/Yuefang/243/72 (H3N2) and virus B.

Ribavirin is a broad-spectrum inhibitor against several unrelated DNA or RNA viruses in vitro and in vivo. In this paper the in vitro and in vivo study of anti-influenza virus activity of ribavirin (RBV) injection had been reported. The in vitro antiviral activity of ribavirin injection against influenza virus A and B was studied by CPE. The in vivo protective action of ribavirin injection against influenza A/FM/1/47(H1N1) mouse adapted strain infected mouse was studied with mouse model. The results showed ribavirin injection has strong inhibitory activity against 7 virus strains tested in vitro. Ribavirin injection could significantly increase virus infected mouse survival rate and survival days and improve lung pathogen and lung index.

For obtaining new structural compounds with unique resistance profiles or novel mechanisms of action on HIV-1 from natural products, anti-HIV-1 drug screening models were used in vitro. Norcantharidin (NCTD), a derivative from cantharidin, was found to have inhibitory activities on HIV-1(IIIB) p24 antigen in lymphocyte lines MT-4, CEM and H9. It inhibited HIV-1 strain 018a (sensitive to zidovudine) from replicating with EC50 (50% effective concentration) of 14.9 micromol L(-1) and also inhibited HIV-1 strain 018c (resistant to zidovudine) from replicating with EC50 of 20.2 micromol L(-1) in primary lymphocytes peripheral blood mononuclear cells (PBMC). Norcantharidin showed synergistic activity with zidovudine on HIV-1(IIIB) in MT-4 cells, the combination index was less than 0.3. But, it was not active on HIV-1 integrase, reverse transcriptase or protease in vitro. As the structure of norcantharidin is unique and different from that of all clinic drugs approved, it would be possible to obtain new and effective compounds against HIV-1 with low toxicities after modification of norcantharidin.

Cycloheximide (CHX) inhibits protein synthesis in most eukaryotic cells and it is a well-known tool commonly used in biochemical research. In this paper, the antiviral spectrum of CHX against several DNA and RNA viruses have been evaluated. CHX showed strong inhibitory activities against several RNA viruses such as HIV-1, influenza viruses, coxsackie B virus, enterovirus (EV71) and several DNA viruses such as HSV and HCMV. Especially the strong inhibitory activities of CHX against coxsackie B virus and enterovirus caught our attention, since effective drugs available in clinic are limited. The SAR of CHX derivatives also has been discussed in the paper. The hydroxyl group at C-2' and carbonyl group at C-2" of CHX are essential for its antiviral activity. And modification to these groups results its derivatives' antiviral activities reduced or lost.

Strict regulation of HIV-1 PR function is critical for efficient production of mature viral particles. During viral protein expression and viral assembly, HIV-1 PR located within Gag-Pol precursor must be inactive to prevent premature cytoplasmic processing of the viral Gag and Gag-Pol precursors. Premature activation of HIV-1 precursors leads to major defects in viral assembly and production of viral particles. A cell-level premature activation of HIV-1 precursors assay using bioluminescence resonance energy transfer (BRET) was established. Three thousand compounds were screened to evaluate this assay. The results showed that the assay is sensitive, specific and stable (Z' factor is 0.905).

The HIV-1 Rev protein facilitates nuclear export of unspliced and singly spliced viral transcripts containing RRE RNA through the CRM1 export pathway. Inhibition of Rev-mediated RNA nuclear export can arrest HIV-1 transcriptional process, which clearly, reveals a target for anti-HIV drug development. In this work, a cell-based assay has been established for screening anti-HIV compounds targeting the Rev-mediated RNA nuclear export. This assay utilized a codon-optimized green fluorescent protein (GFP) as reporter gene, which expression is in a Rev-dependent manner. Any compound that inhibits the Rev-mediated RNA nuclear export is identified by reducing emission of GFP. The Z' score of this model is 0.8220. Three thousands compounds were screened and the positive rate was 9.3% with a cutoff at 50% inhibition. IMB7C7, one of the positive compounds, efficiently inhibits viral production from HIV-1 infected cells.

Apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 protein G (APOBEC3G) is part of the innate immune system of host cells and has cytidine deaminase activity. It specifically incorporates into the virion during HIV-1 replication. The incorporation of APOBEC3G needs its interaction with HIV-1 Gag. In the HIV-1 reverse transcription process, APOBEC3G deaminates dC to dU in the first minus strand cDNA, and then induces extensive hypermutation in the viral genome. Besides deamination, APOBEC3G also inhibits HIV-1 by some kinds of non-deamination mechanisms which need to be further elucidated. HIV-1 Vif counteracts the activity of APOBEC3G by an ubiquitin-proteasome-mediated degradation of APOBEC3G. As a broad spectrum inhibitor of viruses, APOBEC3G also inhibits various retroviruses, retrotransposons and other viruses like HBV. Upregulating the expression of APOBEC3G or blocking the Vif-mediated degradation of APOBEC3G might be novel strategies to treat HIV-1 infection in the future.

Objective: To study the chemical constituents in the root of Salvia yunnansis., Method: Compounds were isolated and purified by Diaion HP20, Sephadex LH - 20, ODS chromatography. Their structures were determined by spectral analysis and chemical evidence., Result: Twelve compounds were isolated and identified from the root of S. yunnansis protocatechaldehyde (1), caffeic acid (2), ferulic acid (3), rosmarinic acid (4), salvianolic acid A (5), salvianolic acid C (6), lithospermicacid (7), lithospermicacid B (8), 9'-methyl lithospermate B (9), 9"'-methyl lithospermate B (10), 9',9'''-dimethyl lithospermate B (11), 9'-ethyl lithospermate B (12)., Conclusion: The compounds 1, 2, 3, 5, 6, 9, 10, 11 and 12 were first isolated from S. yunnanensis.

Atrazine could be used as the sole carbon, nitrogen and energy sources for growth by strain Arthrobacter sp. AG1, and the atrazine-degrading genes of AG1 were found to be the combination of trzN, atzB and atzC. The atrazine chloride hydrolysase gene trzN was cloned by PCR amplification,whose sequence shared 99% identity with that of Norcardioides sp. C190. Two large plasmids were found in AG1,and trzN and atzB were confirmed to be localized on the larger plasmid pAG1 by the method of southern hybridization. Subculture of AG1 in liquid LB for three generations, 34% of the subsequent cells were found to lose degrading activity, however, neither plasmid was lost. PCR amplification results showed that the mutants had only lost the trzN gene instead of atzB and atzC. It was deduced that mutation might be due to the trzN gene deletion from the plasmid. This study provided new evidence that atrazine metabolic genotypes were resulted from horizontal gene transfer between different bacteria under environmental selective pressure.

Pseudomonas putida DLL-1 is a high effective methyl parathion (MP) degrading strain, which is also of chemotaxis to MP. cheA, responsible for coding histidine kinase, plays an important role in bacterial chemotaxis signal transduction. In order to study the effect of bacterial chemotaxis on in-situ biodegradation of pesticides, cheA in chromosome of P. putida DLL-1 was mutated by gene-targeting and successfully obtained a MP-chemotaxis mutant DAK. The mutant DAK shows the same growth ability as wild-type DLL-1 in LB medium. The degrading rate of 50 mg/kg MP in non-sterile and sterile soil of chemotaxis mutant DAK is about 20%-30% lower than that of wild-type bacterial DLL-1. Lose of chemotaxis in DLL-1 would decline its degradation ability of MP. It was demonstrated that chemotaxis plays an important role in the in-situ biodegradation of pesticides.

Atrazine (AT), a kind of herbicide for the pre and post-emergence control of annual and broad leaved weeds and perennial grasses, had been widely used in the world. However, the extensive use of atrazine had led to widespread environmental pollution. A bacterium strain SA1, which could degrade AT completely, was isolated from an atrazine-degrading consortium by long-time repeated alternative cultivation and plate striking. Combining cultural and physiobiochemical characteristics with 16S rDNA sequence analysis, SA1 was identified as Pseudomonas sp.. SAl could use atrazine as the sole carbon, nitrogen and energy sources for growth, and the main product of AT biodegradation was cyanuric acid. AT degrading activity of SA1 was not affected by the addition of nitrogen resources. However, cyanuric acid could be degraded quickly to an undetectable level when glucose was added. The optimal temperature and pH value for SAl growth was 37 degrees C and pH7, respectively. Atrazine could be degraded efficiently by the resting cells of SAl under the conditions of 10 degrees C - 40 degrees C or pH value 4-11, and SA1 had a wide range of temperature and pH value for AT degradation when compared with ADP. atzABCD and conserved sequence of tnpA gene of IS1071 could be amplified from SA1, and these genes could be lost during subculture.

Extended-spectrum beta-lactamases (ESBLs), mediated by plasmids, can hydrolyze and cause resistance to penicillins, broad spectrum-cephalosporins, and monobactams. Most ESBLs are derived from the widespread broad-spectrum beta-lactamases TEM-1 and SHV-1. There are also other families of ESBLs, including CTX-M and OXA-type enzymes as well as novel unrelated beta-lactamases. This article reviews recent advances in the classification, characteristics, and other molecular biological aspects of ESBLs.

The salinity tolerance characteristic of Pseudomonas putida DLL-1 and the environmental factors affecting the salinity tolerance of DLL-1 were investigated. The result showed that the enrichment of culture medium influenced the salt tolerance of DLL-1, in complete medium DLL-1 could survive higher salinities than in chemically defined medium. When inoculated to complete medium with 1mol/L NaCl, the least initial biomass guarantee DLL-1 surviving was 1/100(V/V) of the medium volumes. But when inoculated to chemically defined medium with 1mol/L NaCl, the least initial biomass guarantee DLL-1 surviving was 1/10(V/V) of the medium volumes. The effects of glycine betaine exogenously supplied on the salinity tolerance of DLL-1 and its osmo protection mechanisms were also studied. The results indicated that the glycine betaine present externally could promote the growth of DLL-1 under high salinity. 10mg/L of exogenous glycine betaine was sufficient to promote the growth condition of DLL-1 cells under high salinities. 150mg/L glycine betaine could support DLL-1 cells grow in chemically defined medium with 1.2mol/L NaCl. The presence of glycine betaine in chemically defined medium could reduce significantly the lag time and generation time and increase the final biomass of DLL-1 under salt stress. Compared with the control without exogenous glycine betaine, the lag time of the treatment with exogenous glycine betaine could be reduced from 24h to 6h, and the generation time from 60min to 35.7min, the final OD610 value of culture increased from 1.29 to 1.57. Under osmotic stress, DLL-1 cells could synthesis glycine betaine, trehalose and free amino acid as the main compatible solute. When exogenously supplied, DLL-1 cells accumulated exogenous glycine betaine rapidly from medium to balance the extracellular osmolality instead of the synthesis of compatible solutes.

Ectoine was the main compatible solute of moderately halophilic bacteria. In order to clone the ectABC gene which involved in the ectoine biosynthesis pathway from total DNA of moderately halophilic bacteria Halomonas sp. BYS-1, firstly a 750bp fragment of ectABC gene was amplified by PCR using combinations of forward primers and reverse primers designed according to the ectABC genes of Halomonas elongata 2851T and Halomonas elongata DSM3043. Then the upstream and downstream sequences of the 750bp fragment were amplified by SEFA PCR (SElf-Formed Adaptor PCR), a new PCR method amplified relatively long flanking sequences from tagged sequences in a simple way without enzyme excision and ligation. The 3532bp fragment include 2423bp ectABC, 980bp upstream sequences and 129bp downstream sequences were cloned from Halomonas sp. BYS-1 using a pair of conserved primers designed according to acquired sequences by SEFA PCR. The GenBank accession number of the 3532bp fragment is DQ017757. ORF analysis revealed that ectA, ectB, ectC cluster to an operon, the size of ectA, ectB, and ectC were 573bp, 1251bp and 387bp respectively. The predicted molecular masses of the encoded proteins were 21.1kDa (191 amino acids, EctA), 45.7 kDa (417 amino acids, EctB), and 14.5 kDa (129 amino acids, EctC) respectively. The 3532bp fragment was ligated to the MCS site of vector pUC19 and transformed E. coli DH5alpha to construct E. coli (pUC19ECT). Transformant E. coli (pUC19ECT) could synthesis ectoine under salt stress, the intracellular ectoine level were 7.1, 19.4 and 32.3 micromol/(g x dry x wt) when the salinities of the mediums were 0, 0.4 and 0.8mol/L sodium chloride respectively. But the accumulation of ectoine could not promote the growth of E. coli (pUC19ECT)under high salinity.

Construction of multifunctional pesticides-degrading genetically engineered microorganisms (GEMs) is increasing important in the bioremediation of various pesticides contaminants in environment. However, construction of genetically stable GEMs without any exogenous antibiotic resistance is thought to be one of the bottlenecks in GEMs construction. In this article, homologous recombination vectors with the recipient's 16S rDNA as homologous recombination directing sequence (HRDS) and sacB gene as double crossover recombinants positive selective marker were firstly constructed. The methyl parathion hydroalse gene (mpd) was inserted into the 16S rDNA site of the carbofuran degrading strain Sphingomonas sp. CDS-1 by homologous recombination single crossover in the level of about 3.7 x 10-(7) - 6.8 x 10(-7). Multifunctional pesticides-degrading GEMs with one or two mpd genes inserted into the chromosome without any antibiotic marker were successfully constructed. The homologous recombination events were confirmed by PCR and southern blot methods. The obtained GEMs were genetically stable and could degrade methyl parathion and carbofuran simultaneously. The insertion of mpd gene into rrn site did not have any significant effect on recipient' s physiological and original degrading characteristics. The methyl parathion hydrolase (MPH) was expressed at a relatively high level in the recombinants and the recombinant MPH specific activity in cell lysate was higher than that of original bacterium (DLL-1) in every growth phase tested. The highest recombinant MPH specific activity was 6.22 mu/tg. In this article, we describe a first attempt to use rRNA-encoding regions of Sphingomonas strains as target site for expression of exogenous MPH, and constructed multifunctional pesticides degrading GEMs, which are genetically stable and promising for developing bioremediation strategies for the decontamination of pesticides polluted soils.

Horizontal gene transfer, unlike vertical gene transfer, is a means of genetic communication in bacteria. In the special polluted environment, horizontal transfer of polluted-degrading gene has significant functions. Study on horizontal transfer of degrading gene in polluted environment may deepen our understanding of the mechanism of bacterial adaptation to the organic-polluted environment. In the practical application in bioremediation, horizontal transfer of degrading gene can be regulated to promote degrading ability of microorganisms. In this article, we will review the advances in the study on mechanisms of genetic interactions among bacteria, the effect of degrading gene transfer in contaminated environment on microorganisms'adaptation to contaminated environment and the degradation of the pollutants.

Aim: To study the antitumor mechanism of 3-bromopropionylamino benzoylurea (JIMB01) on leukemia and lymphoma., Methods: The antitumor effects of JIMB01 in cell culture was detected by MTT staining. JIMB01-induced apoptosis in leukemia and lymphoma cells was tested by Giemsa staining, fluorescent Hoechst33258 staining, as well as DNA gel electrophoresis. Cell cycle was analyzed by flow cytometry. JIMB01-induced Bcl-2 phosphorylation in CEM cell lines was detected by Western blot methods. The activities of caspase-3 and caspase-8 were determined by colorimetric protease assay and that of caspase-9 was determined by fluorescent intensity., Results: This compound showed antiproliferative activities in a panel of nine human leukemia and lymphoma cell lines with IC50 values in the range of 0.25 micromol x L(-10 to 0. 51 micromol x L(-1). Morphological observation and cell cycle analysis indicated that CEM cells were blocked at mitosis phase by JIMB01. The fluorescent Hoechst33258 staining showed apoptotic nuclear degradation dispersed in the cytoplasm of CEM cells exposed to JIMB01 at 0. 80 micromol x L(-1) for 24 h. DNA degradation in the form of a multiple-unit DNA ladder was clearly demonstrated in CEM leukemia cells treated with JIMB01 at 0.15 micromol x L(-1) or higher for 24 h using agarose gel electrophoresis. Bcl-2 phosphorylation became visible, in Western blot, within 6 h in CEM cells treated with JIMB01 at 0.15 micromol x L(-1) or higher for 24 h. JIMB01 increased the activities of caspase-3, -8 and -9 in CEM cells; DEVD-fmk, a caspase-3 inhibitor, inhibited the cytotoxicity of JIMB01 in CEM leukemia cells., Conclusion: The antitumor mechanism of JIMB01 is that JIMB01 may induce tumor cell apoptosis through Bcl-2 phosphorylation and then caspase passway.

CCR5, a membrane protein on cell surface, is a member of the G protein-coupled receptor superfamily and one of the major co-receptors for HIV-1 infection. The roles of CCR5 in HIV-1 infection have been elucidated since 1996. Because of the biological nature of CCR5, it has became a molecular target for the novel drugs against HIV-1. Antagonists for CCR5 could be grouped as following, chemokine derivatives, small molecule non-peptide compounds, monoclonal antibodies and peptides. The latest progress in this field is reviewed in this article.

Objective. To construct a cDNA subtractive library of rat brain after repeated + Gz exposures with suppression subtractive hybridization (SSH). Method. Wistar [correction of Wister] rats were randomly divided into control group and repeated +Gz exposure group. Using an animal centrifuge, control rats were exposed to +1 Gz and exposure rats were exposed to +10 Gz for three times, each for 1 min with 30 min interval in between. Brains were taken 6 h after the last centrifuge run and Poly (A) + RNA were isolated. Moreover, single-strand cDNAs and double-strand cDNAs were synthesized in turn. After Rsa I enzyme restriction, +Gz exposure rat brain cDNAs were divided into two groups and ligated to the specific adaptor 1 and adaptor 2R, respectively. Then +Gz exposure rat brain cDNAs were hybridized with the control rat brain cDNA twice and underwent nested PCR twice. The PCR product was ligated with T/A plasmid vectors to set up the subtractive library. Result. The cDNA subtractive library of rat brain after repeated +Gz exposures with high subtractive efficiency was set up successfully. Conclusion. The highly efficient cDNA subtractive library may provide a solid foundation for screening and cloning differentially expressed genes in rat brain after repeated exposures to +Gz.

In order to understand insertion/delation (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene in pilots,and to explore the relationship between ACE gene I/D polymorphism and the performance of the pilots, the polymerase chain reaction (PCR) was used to determine the genotypes for an I/D polymorphism in intron 16 of the ACE gene in 118 pilots and 96 healthy subjects as controls. The result showed that the I/D polymorphism in intron 16 of the ACE gene was categorized into three genotypes: two deletion alleles (genotype DD), heterozygous alleles (genotype ID), and two insertion alleles (genotype II). The genotype II and I allele frequency were significantly higher in pilots (44.07% and 0.65) than that in healthy subjects (31.25% and 0.52). It is suggested that I gene of ACE may play a role in performance of the pilots.