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Novel associations between rhizobial populations and legume species within the genera Lathyrus and Oxytropis grown in the temperate region of china

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Science china(Life Sciences) 2009年第2期52卷 182-192页

作者： SUI XinHua, HAN LiLi, WANG EnTao, JIANG Feng, LIU YiHai & CHEN WenXin State key laboratory for {2.Biotechnology, key laboratory of {2.-microbial resource and application, ministry of Agricul- ture/College of Biological Sciences, china agricultural university, beijing 100193,{12. 1. State key laboratory for {2.Biotechnology Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture/College of Biological Sciences China Agricultural University Beijing 100193 China

Fifty rhizobial isolates of Lathyrus and Oxytropis collected from northern regions of china were studied in their genotypic characterization based upon analyses of ARDRA, 16S-2.S IGS PCR-RFLP, TP-RAPD, MLEE, sequences of 16S rDNA gene and housekeeping genes of atpD, recA and glnII. The results demonstrated that most of the Lathyrus rhizobia belonged to Rhizobium and most of the Oxytropis rhizobia belonged to Sinorhizobium. A novel group of Rhizobium sp. I and S. meliloti were identified as the main microsymbionts respectively associated with Lathyrus and Oxytropis species in the collection area, which were new associations between rhizobia and the mentioned hosts. This study also provides new evidence for biogeography of rhizobia.

关键词： Lathyrus Oxytropis rhizobia genotypic diversity northern china

Screening of Highly Effective Sinorhizobium meliloti Strains for 'Vector' Alfalfa and Testing of Its Competitive Nodulation Ability in the Field

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Pedosphere 2007年第2期17卷 219-228页

作者： ZENG Zhao-Hai CHEN Wen-Xin HU Yue-Gao SUI Xin-Hua CHEN Dan-Ming College of agronomy and Biotechnology China Agricultural University Beijing 100094 （China） College of Biology/key laboratory of {2.-microbial resource and application Ministry of Agriculture China Agricultural University Beijing 100094 （China）

Seventeen Sinorhizobium meliloti strains from seven provinces in china were used to screen highly effective strains for alfalfa cultivar in a greenhouse study and their symbiotic relationship and competitive ability were studied in the field. CCBAU30138 was the most effective strain, as evidenced by increase in dry weights. A field experiment showed that the inoculation of alfalfa with CCBAU30138 resulted in increases of 11.9% and 19.6% of dry matter production and crude protein production, respectively, in forage of monocultured plants. The total dry matter yields of alfalfa and tall fescue in binary culture were increased by 16.3% by inoculation of alfalfa with this strain. These results showed that S. rneliloti strain CCBAU30138 was an effective inoculant both in the greenhouse and in the field. The analysis of randomly amplified polymorphic DNA （RAPD） by polymerase chain reaction （PCR） from nodule extracts showed that the strain CCBAU30138 had high competitiveness in the field. It occupied 47.5% of nodules in alfalfa monoculture and 44.4% of nodules in alfalfa-tall fescue binary culture after 2. weeks of growth. In conclusion, a simple system to select highly effective and competitive symbiotic strains specific to alfalfa was established. Using this system, a *** suitable for the alfalfa cultivar ‘Vector＇ grown in Wuqiao County of Hebei Province was obtained.

关键词： alfalfa inoculant selection Sinorhizobium meliloti tall fescue

The secretion of lecithinase of Pseudomonas alcaligenes S2.was via type II secretion pathway

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Science Bulletin 2005年第16期 61-66页

作者： Lü Jing1, LI Fan1, CHEN Sanfeng1,2.& LI Jilun1,3 1. State key laboratory of {2.biotechnology, china agricultural Uni-versity, beijing 100094, china 2. key laboratory of {2.-microbial resource and {12. in Agri-culture ministry, china agricultural university, beijing 100094, china 3. College of Biological Sciences, china agricultural university, beijing 100094, china

Strain S2.is a lecithin (or phosphatidylcholine)- solubilizing bacterium, which was isolated from the rice rhizosphere in rural areas of beijing, china. On the basis of a polyphasic study involving phenotypic tests, physiological and biochemical tests, 16S rDNA sequence analysis, G+C content determination and DNA-DNA hybridizations analy-sis, strain S2.was identified as Pseudomonas alcaligenes. P. alcaligenes S2.was mutagenized with Tn5 and four mutants showing decreased or increased solubilizing ability of lecithin were isolated based on the halo size around colonies on the solid plate supplemented with egg yolk. To characterize the genes of P. alcaligenes S2.involved in solubilization of lecithin, the EcoR I fragments of the chromosomes from the four mutant strains carrying a single transposon were cloned, and the DNA sequences flanking the Tn5 were determined. The Tn5 insertion sites in the mutants M808, M132. and M1400, showing decreased solubilizing ability of lecithin, were found to be located in the xcpS, xcpX and xcpW , respectively, whose products XcpS, XcpX and XcpW were the components of type II secretion pathway. Complementation of xcpS, xcpX and xcpW could restore the corresponding mutants M808, M132. and M1400 to solubilize lecithin. The data suggested that mutation in one of these xcp genes would lead to the absence of mature lecithinase secretion into the extracellular medium. The data also indicated that the secretion of leci-thin-hydrolyzing enzyme of P. alcaligenes was via type II secretion pathway. In the mutant M2. showing increasing lecithin-hydrolyzing activity, the interrupted gene showed 86% identity with chpA of Pseudomonas aeruginosa PAO1, whose product plays an important role in controlling twitch-ing motility of the bacterial cells.

关键词： Pseudomonas alcaligenes mutants lecithin solubilization Tn5.

Vertical distribution of phosphorus and P-dissolving/ decomposing bacteria in the sediment of Guanting reservoir

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Science china Earth Sciences 2005年第Z2期48卷 285-294页

作者： LI Cui, YUAN Hongli & HUANG Huaizeng College of Biological Sciences, key laboratory of {2.-microbial resource and application, ministry of agriculture, china agricultural university, beijing 100094, china National Research Center of Geoanalysis, beijing 100037, china College of Biological Sciences Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture China Agricultural University Beijing 100094 China National Research Center of Geoanalysis Beijing 100037 China

In this study, we determined pH, phosphorus content and the number of P-dis- solving/decomposing bacteria in relation to the depth in the sediment of Guanting reservoir in beijing. The pH value was slightly increased from 8.0 in the surface to 8.5 in the bottle (69 cm in depth) of sediment. The highest P content, 12.9 mg/kg, was detected in the 35 cm layer, followed by the 5 cm (993 mg/kg) and 69 cm (580 mg/kg) layers. The number of inorganic P-dissolving bacteria varied from 6(102.to 8(104 and the organic P-discomposing bacteria were from 1.9(103 to 6.3(104 per gram sediment in different depths, which were counted under 2.℃ and 2.℃ ( pH7.5 and 8.5. The number of P-dissolving/discomposing bacteria was directly correlated to the P content in each layer of sediments. The analysis of P-dissolving/decomposing ability of bacteria showed that some of these bacteria were also capable of accumulating P intracellularly. The intracellular P-accumulation was more efficient at lower temperature; in contrast, the activity of P-dissolving/decomposing was stronger at higher temperature. So the content of dissolved P in water body, or quality of water, could be affected by the change of temperature via the regulation of bacterial activity. On the basis of 16S rDNA sequencing, the 13 efficient P-dis- solving/decomposing bacteria were identified as Bacillus spp., Bacterium sp., Microbacterium sp., Paenibacillus sp. and Pseudomonas sp.

关键词： Guanting reservoir, sediment, P-dissolving/decomposing bacteria, phosphorus cycling, eutrophication.

Epigenetic reprogramming in mammalian nuclear transfer

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Chinese Science Bulletin 2004年第8期49卷 766-771页

作者： LI Shijie1,2. DU Weihua1 & LI Ning1 1. State key laboratory for {2.biotechnology, china agricultural university, beijing 100094, china 2. Department of Biochemistry and Molecular Biology, College of Life Science, Hebei agriculture university, Baoding 071001, china Correspondence should be addressed to Li Ning (e-mail: ninglbau@ ***) State key laboratory for {2.biotechnology China Agricultural University Beijing 100094 China Department of Biochemistry and Molecular Biology College of Life Science Hebei Agriculture University Baoding 071001 China

Somatic cloning has been succeeded in some species, but the cloning efficiency is very low, which limits the application of the technique in many areas of research and biotechnology. The cloning of mammals by somatic cell nuclear transfer (NT) requires epigenetic reprogramming of the differentiated state of donor cell to a totipotent, embry-onic ground state. Accumulating evidence indicates that in-complete or inappropriate epigenetic reprogramming of do-nor nuclei is likely to be the primary cause of failures in nu-clear transfer. This review summarizes the roles of various epigenetic mechanisms, including DNA methylation, histone acetylation, imprinting, X-chromosome inactivation, te-lomere maintenance and expressions of development-related genes on somatic nuclear transfer.

关键词：哺乳动物细胞核液迁移后成程序改编 DNA甲基化作用组蛋白乙酰化作用 X-染色体活化端粒印痕基因表达克隆

QSAR and 3D-QSAR studies of the diacyl-hydrazine derivatives containing furan rings based on the density functional theory

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Science china Chemistry 2010年第6期53卷 1322-1331页

作者： ZHANG Li1,2.CUI ZiNing1,YIN Bin1,YANG GuangFu2.LING Yun1 & YANG XinLing1 1key laboratory of Pesticide Chemistry and {2. Technology,ministry of agriculture Department of Applied Chemistry,College of Science,china agricultural university,beijing 100193,china 2.0} laboratory of Pesticide & Chemical Biology,ministry of Education,Huazhong Normal university,Wuhan 430079,china 1. key laboratory of Pesticide Chemistry and {2. Technology Ministry of Agriculture Department of Applied Chemistry College of Science China Agricultural University Beijing 100193 China2. Key Laboratory of Pesticide & Chemical Biology Ministry of Education Huazhong Normal University Wuhan 430079 China

QSAR studies of 2. diacyl-hydrazine derivatives containing furan rings were conducted and compared with the DFT method and AM1-MOPAC method.q2.values of 0.61 and 0.40 validated the predictability and reliability of eq.(5) from the DFT method were higher than those of eq.(6) from the AM1-MOPAC *** DFT-optimized conformations and ESP-fitting charges of the target compounds were also used for 3D-QSAR analysis,including CoMFA and *** leave-one-out cross-validation correlation coefficient and the good correlation between the predicted and experimental activities of excluded test compounds revealed that CoMFA and CoMSIA models were *** QSAR results were consistent with the 3D-QSAR results,indicating that the electrostatic and hydrophobic properties of the target compounds were significant to the biological *** models are useful tools for predicting the larvicidal activities of new compounds and designing new specific insect growth regulators.

关键词： diacyl-hydrazine QSAR 3D-QSAR DFT insect growth regulator

Phenanthrene-degrading pathway of agrobacterium sp. Phx1

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Science china Earth Sciences 2005年第Z2期48卷 269-275页

作者： ZHANG Lei, YUAN Hongli, WANG Shuangqing & HUANG Huaizeng College of Biological Sciences, key laboratory of {2.-microbial resource and application, ministry of agriculture, china agricultural university, beijing 100094, china National Research Center of Geoanalysis, beijing 100037, china College of Biological Sciences Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture China Agricultural University Beijing 100094 China National Research Center of Geoanalysis Beijing 100037 China

The metabolic pathway of phenanthrene-degrading strain agrobacterium sp. Phx1 was investigated. Phx1 almost was able to transform 100 υg/mL of phenanthrene completely in 1 day in broth media of beef extract-peptone (BP), Luria-Bertani (LB) and mineral salts media (MS), and LB and BP could promote the growth and degradation efficiency of Phx1. The GC-MS was employed to analyze the metabolites of the 1st, 3rd, 7th days of phenanthrene degradation in MS. As a result, the 1-Hydroxy-2.naphthoic acid (1H2.) and 1-naphthol (NOL) were detected in the metabolites of the 1st day. Only NOL was observed on the 3rd day and it disappeared on the 7th day. The accumulated NOL did not pertain to the defined pathway of phenanthrene degradation by bacteria. The further HPLC study confirmed the finding in GC-MS analysis and found the production of catechol (CAT) from o-phthalic acid (OPA) in the phenanthrene metabolizing, which has never been reported in the defined degrading pathways. This production was also evidenced by the production of CAT using OPA as substrate. All of our results showed that the agrobacterium sp. Phx1 had a novel phenanthrene-degrading pathway.

关键词： agrobacterium, phenanthrene, metabolic pathway, 1-naphthol, o-phthalic.

Mechanism of cadmium resistance and adsorption of a yeast strain Rhodotorula sp. Y11

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Science china Earth Sciences 2005年第Z2期48卷 262-268页

作者： YUAN Hongli, LI Zhijian, WANG Nengfei & HUANG Huaizeng College of Biological Sciences, key laboratory of {2.-microbial resource and application, ministry of agriculture, china agricultural university, beijing 100094, china National Research Center of Geoanalysis, beijing 100037, china College of Biological Sciences Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture China Agricultural University Beijing 100094 China National Research Center of Geoanalysis Beijing 100037 China

The mechanism of cadmium resistance of a yeast strain Rhodotorula sp. Y11 isolated from mine soil was investigated. We found that the yeast cells treated with different methods showed different cadmium-adsorption models. Grown in medium supplied with 100 mg/L of cadmium, 3.2.% of the cell-absorbed cadmium was accounted in the cytoplasm. However, only 1% was taken into the cytoplasm and 99% was bound to the cell wall using the lyophilized biomass to adsorb cadmium in double distilled water. Treatments with alkali, ethanol-chloroform and proteinase showed different influences on the biosorption of whole cells and isolated cell walls. FT-IR analysis showed that acetyl of chitin was the active compound in the cells to absorb cadmium. The production of Metallothioneins, proteins related to the resistance to heavy metal in yeast, was evidently induced by cadmium, achieving 638.8 μg/g wet weight, which was about 85 folds higher than that in the uninduced biomass and was also much higher than that reported previously. The molecular weight of Metallothioneins was 6500 Da estimated by SDS-PAGE.

关键词： cadmium, adsorption, Rhodotorula sp., cell wall, Metallothionein.

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, LI Xiaoying1,2.3, ZHANG Yong1,2.3, ZHAO Feng1,2.3, GU Xingfa1,3,4, ZHU Li1,2.3, WANG Pengxin5 & MIN Xiangjun6 1. State key laboratory of Remote Sensing Science Institute of Remote Sensing {2., CAS, Bei- jing 100101, china 2. Graduate university of Chinese Academy of Sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of Information and Electrical Engineering, china agricultural university, beijing 100083, china 6. china Center for resource Satellite Data and {2., beijing 100830, china 1. State key laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate university of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche agronomique Climat Sol Environnent 84914 Avignon France 5. College of Information and Electrical Engineering China Agricultural University 100083 Beijing China 6. china Center for resource Satellite Data and {2. 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.