变棕溶杆菌OH23次生代谢产物抗菌活性的分析及其发酵培养基优化

本研究通过对变棕溶杆菌Lysobacter brunescens OH23菌株发酵产物的拮抗谱进行检测,发现其发酵产物对黄单胞属植物病原细菌具有特异拮抗活性,并且对水稻黄单胞菌不同菌株的拮抗活性存在差异。本研究进一步对OH23次生抗菌物质稳定性进行了分析,发现OH23产生的次生抗菌物质对高温、紫外光照、蛋白酶、非强碱性环境均表现稳定,但在强碱性环境(pH11.0)下拮抗活性丧失。最后,采用单因素试验和正交试验设计对OH23发酵培养基组分进行了优化,最终确定OH23高产次生抗菌物质的培养基配方为高聚蛋白胨5g/L、酵母粉5g/L、可溶性淀粉6g/L、FeSO4·7H2O15mg/L、ZnSO4·7H2O5mg/L。

Crystallization of Nitrogenase MoFe Protein from a Mutant nifE Deleted Strain of Azotobacter vinelandii

Under a suitable condition of crystallization, dark brown short rhombohedron crystals could be obtained from FeMoco-deficient MoFe protein (DeltanifE Avl) purified from a nifE deleted mutant DJ35 of Azotobacter vinelandii Lipmann grown in NH3-limited medium. The number, size and quality of crystals were significantly affected by either the concentration of precipitants and buffer or diffusion method. The longest sides of the largest crystal of DeltanifE Avl protein, which was obtained by vapor diffusion in the hanging drop method, were 0.12 and 0.13 mm, respectively.

Purification and Characteristics of Mn-containing Nitrogenase Component Ⅰ

A mutant UW 3, which is unable to fix N 2 in the presence of Mo (Nif -) but undergo phenotypic reversal to Nif + under Mo deficiency, was able to grow in Mo- and NH 3-deficient medium containing Mn, and the growth was accelerated by Mn at low concentration. A partly purified nitrogenase component Ⅰ protein separated from UW 3 grown in the Mn-containing medium was shown to contain Fe and Mn atoms (ratio of Fe/Mo/Mn: 10.41/0.19/1.00) with C 2H 2- and H +-reducing activity which almost equal to half of that of MoFe protein purified from wild-type mutant of Azotobacter vinelandii Lipmann. This protein was obviously different from MoFe protein in both absorption spectrum and circular dichroism, and the molecular weight of subunits in Mn-containing protein was close to that of α subunit in MoFe protein. The preliminary results indicated that the protein containing Mn might be a nitrogenase component Ⅰ protein.

Studies on Crystalline Growth of MoFe Protein from a nifZ Deleted Strain of Azotobacter vinelandii

Under a given condition of crystallization, dark brown short rhombohedron crystals could be obtained from Δ nifZ MoFe protein purified from a nifZ deleted mutant strain of Azotobacter vinelandii Lipmann. Systematic studies on the effect of concentrations of PEG 8000,MgCl 2, NaCl,Tris and buffer pH on the crystallization and crystal growth of the protein showed that the protein could not be crystallized in lower concentrations of the chemicals and lower buffer pH. A large amount of smaller crystals of the protein appeared in a week with gradual increasing in the chemical concentrations and pH≥8.0. When the chemical concentrations were further increased, the time for crystallization was increased and a few high grade crystals of larger size were formed. If the concentrations of the chemicals were continuously increased, many crystals with smaller size, and, sometimes of poor quality appeared again and eventually ceased to produce any crystals. The optimal concentration for each of the above mentioned chemicals varies with other variable factors. Only one bigger crystal (both of the longest two sides: 0.16 mm) could be obtained in a hanging drop of protein sample when the concentrations of PEG 8000, MgCl 2, NaCl,Tris and protein were kept at 1.86%, 300 mmol/L, 400 mmol/L, 53 mmol/L and 4.64 g/L , respectively, with Tris buffer pH 8.2.

Effects of fractal surface on rheological behavior and combustion kinetics of modified brown coal water slurries

The paper reports the effects of surface fractal structures on the rheological behavior and combustion kinetics of raw brown coal and three modified coal water slurries （CWSs）. The results show that the fractal structures and physicochemical properties of samples are dependent on various modification processes. The apparent viscosities of the coal water slurries increase with increasing surface fractal dimensions （D）, especially with decreasing shear rates. Fur- thermore, it has been proved that the ignition temperatures and apparent activation energies of modified CWSs are lower than that of raw coal water slurry. Compared with the traditional qualitative analysis of the effect of pore structures on CWSs properties, D can more efficiently indicate the quantificational effect of pore structures on the rheological behavior and combustion kinetics of CWSs.

Growth of Large Single Crystals of Nitrogenase CrFe Protein and MnFe Protein

By using the liquid/liquid diffusion method at a suitable crystallization conditions, large single and dark brown crystals (the sides of the largest crystals were 0.20 mm x 0.20 mm x 0.07 min and 0.18 mm x 0.18 mm x 0.05 mm, respectively) could be obtained from the solutions of nitrogenase CrFe protein and MnFe protein purified from a mutant UW3 of Azotobacter vinelandii Lipmarm grown in Cr- or Mn-containing but NH3-free medium. The time of crystal formation, as well as the number, size, shape and quality of crystals obviously depended on the concentrations of PEG, MgCl2 and NaCl. The liquid/liquid diffusion method seems to benefit CrFe protein and MnFe protein for the growth of large single crystals for X-ray diffraction analysis.

Crystallization of Nitrogenase MoFe Protein (NifB Av1) from a nifB Mutated Strain UW45 of Azotobacter vinelandii

Six hundred and 28 mg of NifB(-) Av1 was obtained by a chromatography twice on DE 52 columns and Sephacryl S-300 column from the crude extract (37 677 mg) of a nifB mutated strain UW45 of Azotobacter vinelandii Lipmann. The protein was almost homogeneous as determined by Coomassie staining of SDS gels. The analysis by SDS-PAGE showed that NifB(-)Av1 was similar to Av1 from wild-type strain of A. vinelandii (OP) in the kinds of subunits (alpha and beta subunit). When complemented with Av2, NifB(-)Av1 had hardly any H-reducing activity, but could be significantly activated by FeMoco extracted from Av1. Under a suitable condition for crystallization, short dark-brown rhombohedral crystals could be obtained from NifB(-)Av1. Both of the longest sides of the biggest crystal were 0.1 mm. The time of the formation of crystals and number, size, quality and shape of crystals obviously depended not only on the kinds and concentrations of the components in the precipitant solution, but also on the methods for crystallization and technical bias, etc. The preliminary results showed that the crystal seemed to be formed from NifB(-)Av1.

Purification and Activation In Vitro of MoFe Protein from a nifE Deleted Mutant Strain of Azotobacter vinelandii

The Deltanif E MoFe protein (Deltanif E Av1) was obtained by a chromatography on DE52, Sephacryl S-300 and Q-Sepharose columns from the unheated crude extract of nifE-deleted mutant strain (DJ35) of Azotobacter vinelandii Lipmann. The analysis by SDS-PAGE showed that the Delta nif EAv1 was similar to OP MoFe protein (Av1) of A. vinelandii in the kinds and molecular weights of subunits (alpha and beta subunit). When complemented with nitrogenase Fe protein (M), the A nif EAv1 had hardly any proton-reduction activity, but could be significantly activated by FeMoco extracted from OP Av1. After the Delta nif E Av1 was treated with an excess o-phenanthroline (o-phen) and chromatographied on Sephadex G-25 column under atmosphere of Ar, Delta nif E Av1(C) was obtained. In the presence of both Av2 and MgATP regeneration system, the Delta nif EAv1(C), rather than A nif EAv1, was significantly activated in vitro by a reconstituent solution containing Mn which composed of KMnO4, ferric homocitrate, Na2S, Na2S2O4 (DT) and dithiothreitol (DTT). But in the absence of MgATP or Av2, the activation of Delta nifE Av1(C) did not happen. It indicates that activation of Delta nif EAv1 by RS-Mn requires the pretreatment with o-phen and the simultaneous presence of Av2 and MgATP.

Effect of Zinc Sulfate against the Red Palm Weevil Rhynchophorus ferrugineus with Reference to Their Histological Changes on the Larval Midgut and Adult Reproductive System

The red palm weevil Rhynchophorusferrugineus is the most important insect pest for the date palm trees in the Middle East and Gulf states. Zinc sulfate （ZnSOa＇H20） was toxicologically, biologically and physiologically evaluated as insect development disruptors against the RPW. LCs0 of Zinc sulfate against 10 days old larvae was 0.566%, 3% concentration inhibited the larvae from feeding. LCs0 concentration of zinc sulfate solution was capable to disrupting growth, development and reproduction of R. ferrugineus. Growth and development disruptions are resulted from larval feeding on the treated diet that causing percentage of mortality rate, retardation in larval and pupal duration, percentage of pupation, adults emergence, reduction in deposited eggs that laid by the resulting adults and in the egg fertility. The study further reveals that Zinc sulfate effects on histological structure of epithelial cells of the larval midgut including separation and elongation of their cells, rupture in the peritrophic membrane and in some microvilli and some degeneration of the surrounding muscles. Histological changes also was observed on the adults ovary, in this way, disrupt female gamete production through their action on the accumulation of yolk granules （vitellogenesis） and follicular epithelial cells. Disruption of male gamete production was detected by disorganized of testicular cysts and depopulation of these cysts in addition to degeneration in germ cells. Zinc sulfate may be used among other control methods by injection into the tree trunk or as fertilizer around the tree roots which in turn may have an indirect effect for controlling the RPW.

Egg color polymorphism and morph-ratio variation in Korean populations of the Vinous-throated Parrotbill

Understanding the occurrence of multiple distinct phenotypes in a population of a species,i.e.,polymorphism,is one of the challenges encountered in evolutionary biology.Egg color polymorphism in birds is one example of morphological polymorphism and disruptive selection has been proposed as a hypothetical mechanism to explain its occurrence.We studied how polymorphic egg colors(immaculate blue and white) occur in Korean populations of the Vinous-throated Parrotbill(Paradoxornis webbianus).Egg color ratios(the proportion of nests with blue eggs in a population) were monitored over a large spatial scale and egg colors were quanti ed using a spectrophotometer.We found egg color ratios to vary spatially among populations.Interestingly,there was a latitudinal morph-ratio cline in egg color ratios.e proportion of nests with blue eggs increased considerably with the latitude declined towards the southern part of the Korean peninsula.ere were some quantitative variations in egg colors among populations.However,the pattern of variations was not consistent with those of the population egg color ratios.Based on these results,we discuss a potential scenario for the evolution of egg color polymorphism in the Vinous-throated Parrotbill.

Oil Palm Soil Variability in West Malaysia as Affected by Its Parent Materials

The research aimed to analyze soil variability induced by parent materials for oil palm in West Malaysia. The research results can provide basic information on potential reserves of nutrients to improve soil productivity for oil palm. Soil samples were collected from two locations （granite soils and basalt soils）. The collected soil samples were completely analyzed in laboratory. The research results showed that based on mineral resistance to weathering （sand and silt mineral sizes）, mineral weathering of granite and basalt is divided into three categories, i.e., very slow weathered mineral （quartz and muscovite）, slowly weathered mineral （K-feldspar, Na and Ca-feldspar and biotite）, and easily weathered mineral （hornblende, augit, olivine, dolomite, calcite and gypsum） Losing mineral during weathering process from granite to clay is determined by containing mineral in rocks. Such minerals （CaO, Na：O, KzO, MgO and SiO2） loosed 100%, 95.0%, 83.5%, 74.7% and 52.5%, respectively, but Fe203 is disappeared only 14.4%. Soil properties characters of granite soil is more acid, has very low to low chemical soil fertility and is dominated by sand fraction, furthermore basalt soil is acid, has low to moderate chemical soil fertility and is dominated by clay fraction. Granite and basalt soils are able to produce FFB of oil palm （Fresh Fruit Bunches） 13-18 ton/ha in a year and 19-24 ton/ha in a year, respectively. The production difference of both soils is around 6.0 ton/ha in a year.

Evaluation of New Insecticide （Proteus 170O - TEQ） for the Control of the Brown Cocoa Mirid （Sahlbergella Singularis） in Nigeria

Proteus 170O - TEQ insecticide was subjected through rigorous testing over years （2005 to 2008） at four concentrations 0.15% （9 mls/10L.H20）, 0.31% （18 mls/10L.H2O）, 0.46% （27 mls/10L.H2O） and 0.61% （36 mls/10L.H2O）. Each concentration was replicated three times in the field. The mortality rates of mirids on exposure to the various concentrations of Proteus and Standard miricide in the laboratory were similar at 0.46% concentration as both gave a 100% kill ofmirids at the 40th minute. The first year field mortalities of mirids recorded 24 hours after the initial and residual applications at the Ibadan, Owena and Ikom at 0.46% active ingredient concentration gave 100% kill of mirids. The mortalities of mirids recorded 24 hours after the second year field initial and residual treatments at the lowest concentration of 0.15% active ingredient ranged between 70.2% and 100%. In the third year, the insecticide at 0.31% concentration compared favourably with the Standard. The residues of thiacloprid in the analyzed cocoa bean samples were below the Limit of Quantitation （LOQ） of 0.01 mg/kg. Spraying of mature and fruiting cocoa farms at application rate of 0.46% was found adequate and recommended.

Preliminary Study on Geographical Variation of Cytochrome b gene and ITS2-rDNA among Populations of Rhynchophorus ferrugineus

The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several countries of the Mediterranean Basin, Caribbean （Island of Curacao, Netherland Antilles）, Lebanon and United States of America （Laguna Beach, Orange County, California） during the last three decades where it attacks palm trees. This study investigated the geographical variation among geographic populations of RPW collected from twelve invaded countries using cytochrome b （Cytb） and ITS2 partial sequences. The comparison among the Cytb sequences resulted in three different haplotypes designated as HB 1 to HB3. The three haplotypes were subdivided into two phylogenetic groups according to their geographic positions： （1） the ＂Multi-Continent＂ group containing HB 1 haplotype detected in eight populations belonging to three different Continents such as Africa-Egypt, Asia-Kingdom of Saudi Arabia and Turkey and Europe-Spain, Italy, Greece, Cyprus and France, and （2） the ＂Asian＂ group includes four populations from Iran （harboring HB2 haplotype）, Pakistan, UAE, and Oman （harboring HB3 haplotype）. This mitochondrial pattern of genetic diversity suggests that the tested RPW populations subdivided genetically into different sub-populations under the influence of genetic drift. According to these results we concluded that the twelve studied RPW populations are originating from different source populations in the RPW area of origin.

Genetic Variation and Heritability Estimates for Bunch Yield, Bunch Components and Vegetative Traits in Oil Palm Interspecific Hybrids

Progeny testing of oil palm interspecific hybrids was conducted in four trials in Kluang, Ulu Paka, Teluk Intan and Carey Island, Malaysia. The interspecific hybrids （O × P） were created according to the North Carolina Model I （NCM I） mating design, using Elaeis oleifera （0） and Elaeis guineensis var. pisifera （P） as the maternal and paternal parents, respectively. Differences among O, P and O-within-P were determined by the performance （bunch yield, components and vegetative traits） of the progenies. There were significant differences among P for fresh fruit bunch （FFB） yield, bunch number （BN） and average bunch weight （ABW） in Kluang, Ulu Paka and Teluk Intan, but not in Carey Island. FFB yield was generally higher on coastal soils （Teluk Intan and Carey Island） than inland soils （Kluang and Ulu Paka）. Heritability was calculated based on the intraclass correlation. Heritability estimates for these three yield components were variable, depending on the breeding material and environment in which the materials were tested. Fruit to bunch （F/B） and oil to bunch （O/B） of parthenocarpic fruits were important in determining the overall O/B of the interspecific hybrids. The O x P hybrids in Kluang showed the lowest height increment with only a mean of 14.0 cm/year, whereas in Ulu Paka and Teluk Intan, the values were higher at 24.0 cm/year and 25.0 cm/year, respectively. The study showed that the FFB yields ofoil palm interspecific hybrids performed better in coastal soils than inland soils.

罂粟的教训

海洛因、大麻及可卡因是当今给人类带来深重灾难的世界三大毒品,其中毒害最烈的当数海洛因。 提起海洛因,人们自然就会想到曾给中国人民带来无穷灾难的鸦片。其实,海洛因、鸦片(包括吗啡)皆出自罂粟。罂粟是一种草本植物,夏季开花,花色姹紫嫣红,极美丽。花谢后,用刀在罂粟果实上划开切口,会渗出乳液,不久乳液凝固变棕黑色,此时用刀刮下,就成了举世闻名的、有“美丽杀手”之称的鸦片。

Change in the Distribution of National Bird (Himalayan Monal) Habitat in Gandaki River Basin, Central Himalayas

Gandaki River Basin(GRB) is part of the central Himalayan region, which provides habitat for numerous wild species. However, due to changes in climate and land cover, the habitats of many protected species are at risk. Based on the maximum entropy(MaxEnt) model, coupled with bioclimatic layers, land cover and DEM data, the impacts of environmental factors on habitat suitability of Himalayan Monal(Lophophorus impejanus), a national bird of Nepal, was quantified. This study further assessed the present and future habitat and distribution of the Himalayan Monal in the context of climate and land cover changes. The results of this study show that the highly suitable habitat of Himalayan Monal presently occupies around 749 km^2 within the northern, eastern and western parts, particularly protected areas such as Langtang National Park, Manaslu Conservation Area and Annapurna Conservation Area, while it is likely to decrease to 561 km^2 by 2050, primarily in the northern and northwestern parts(i.e., Chhyo, Tatopani, Humde and Chame). These expected changes indicate increasing risk for Himalayan Monal due to a decline in its suitable habitat area.

Assessing display variability in wild brown anoles Anolis sagrei using a mechanical lizard model

Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The brown anole Anolis sagrei has a high degree of variability in its signature bobbing display. In this study we collected descriptive data on variability in the temporal structure of wild brown anole bobbing patterns, finding that no two displays analyzed had the same temporal structure, and we also tested whether wild brown anoles prefer the signature display over an alternate display pattern by using mechanical robot playbacks in the field. As a response metric we assessed whether or not the lizards showed social responses （pushup, dewlap extension, or head-nod） in response to the robotic presentations. We found that the lizards responded slightly more to the signature than to the alternate pattern, providing support for the idea that despite the variability seen in displays, the signature pattern is meaningful to them. We tested two other independent variables： speed of the display and elevation of the robot during its display, neither of which was significant. Dewlap extensions were given predominantly by adult males and were more likely to be given in the breeding season than the nonbreeding season. Pushups and head-nods were given equally by males and a combined class of females and juveniles, and were not seasonal. Head-nods increased after the robot turned off, suggesting that they may be used in a conversational turn-taking style during communication .