鳞绿泥杆菌对马铃薯瓢虫幼虫体内酶活性的影响

重点介绍了用鳞绿泥杆菌对马铃薯瓢虫幼虫体内的几种酶活性的影响。实验表明,鳞绿泥杆菌对于马铃薯瓢虫体内几种酶的活性有着不同程度的影响。     

Agricultural potential of Mediterranean grain and forage legumes: 2) Anti-nutritional factor concentrations in the genus Vicia

As part of an investigation into the agricultural potential of under-exploited Mediterranean Viceae, anti-nutritional factor concentrations were measured in the seed of 7 species. These included: V. sativa(subsp. amphicarpa(L.) Batt., subsp. macrocarpa(Moris) Arcang, subsp. nigra(L.) Ehrh., subsp. sativa), V. ervilia L., V. faba L. (var. faba, var. minor Peterm.), V. narbonensis L. (var. aegyptiaca Kornhuber ex Asch. et Schweinf., var. affinis Kornhuber ex Asch. et Schweinf., var. jordanica H. Schaef., var. narbonensis, var. salmonea(Mout.) H. Schaef.), and relatives, including V. johannis Tamamsch., (var. johannis, var. procumbens H. Schaef.), V. hyaeniscyamus Mout., and V. serratifolia Jacq. Both quantitative and qualitative differences in seed chemistry were observed. Condensed tannins, phenolics and proteinase inhibitors were found in varying concentrations in all taxa. The highest concentrations of phenolic secondary metabolites (0.8–1.4% leucocyanidin equivalents, 9.5–16.4 mg/g phenolics) were found in V. faba, the V. narbonensis relatives and V. sativa subsp. macrocarpa. These taxa also tended to contain low levels of proteinase inhibitors (0.25-0.55 mg trypsin/mg protein), whereas the opposite was the case for V. ervilia(2.1 mg t/mg p). V. narbonensis was intermediate both in terms of tannin and proteinase inhibitor levels. In contrast, the non-protein amino acids tended to be more specific in their distribution. Concentrations of canavanine varied from 0.04-0.11% in the seed of V. ervilia, and may constrain the end-use of the grain, given that pigs are sensitive to concentrations as low as 0.08% in their diet. In V. sativa variation of -glutamyl--cyanoalanine within and between subspecies (0.41–1.36%) is not sufficient to make the grain palatable to monogastrics, since > 0.075% inclusion in the diet causes mortality in chicks. In V. narbonensis, there was no significant variation between most varieties for -glutamyl-S-ethenyl cysteine (GEC), a non-protein amino acid peptide which reduces grain palatability. However, lower concentrations were found in V. n. var. jordanica and its near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia(1.3-1.6%, compared with 1.9+/–0.02% in all remaining V. narbonesis sub-species). Anti-nutritional factor concentrations were used to visualize taxonomic relationships using hierarchical cluster analysis. The V. narbonensis varieties were closely aligned with their near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia. In contrast V. faba was positioned closer to the V. sativa subspecies than either to V. narbonesis or its near relatives. V. ervilia was the most distantly related species. Across all taxa proteinase inhibitors and condensed tannins or total phenols were negatively correlated (r=– 0.72, P < 0.009). This may be a mechanism which minimizes wasteful resource allocation to chemical defense, because the 2 anti-nutritional factors are functionally substitutable, since they both reduce the availability of protein in plant material. Thus taxa investing in high concentrations of proteinase inhibitors do not duplicate chemical defense mechanisms by simultaneously producing large amounts of tannins and phenolics.     

外源茉莉酸甲酯处理茶树对茶尺蠖幼虫生长的影响

 研究了应用外源茉莉酸甲酯处理茶树后，对茶树叶片中脂氧合酶、多酚氧化酶和蛋白酶抑制素活性，以及对茶尺蠖幼虫中肠蛋白酶活性和生长的影响。结果表明，应用外源茉莉酸甲酯喷雾法或暴露法处理茶树，都能够诱导茶树叶片脂氧合酶、多酚氧化酶和蛋白酶抑制素活性增加，茶尺蠖幼虫中肠强碱性类胰蛋白酶活性和类胰凝乳蛋白酶活性受抑制，但弱碱性类胰蛋白酶活性未受抑制，从而导致茶尺蠖幼虫中肠内各种蛋白酶间的协调性遭到破坏，生长受阻，这可能是茉莉酸甲酯诱导茶树对茶尺蠖幼虫产生直接抗性作用的一种机制。     

福菇肽在灵芝生产上的应用

在灵芝生长的转换期喷施福菇肽，能有效地调节灵芝菌体内蛋白酶的代谢过程，抑制灵芝菌体内酸性蛋白酶的活力，提高中性蛋白酶的活力，促进灵芝子实体形成，加速子实体生长，提高营养利用率，既能增加灵芝产量，又能提高灵芝质量。     

草菇蛋白酶的分离与纯化

草菇是我国食用菌主要栽培品种之一,属于典型的高温真菌,低温将诱导草菇细胞内的蛋白质降解,导致草菇菌丝自溶、死亡。蛋白酶在草菇低温自溶过程中起了重要作用。草菇子实体经破碎、(NH_4)_2SO_4分步沉淀、Sephadex G-150凝胶过滤,获得草菇蛋白酶样品,为草菇的低温自溶与蛋白酶之间关系的研究奠定了基础。     

利用酒糟制备酶类饲料添加剂的研究

利用筛选出的链霉菌属 342号菌 ,以酒糟为原料 ,通过固体发酵法制备酶类饲料添加剂。该添加剂每克干物质含糖化酶 4 32单位 ,蛋白酶 339 0 5单位 ,粗蛋白 19% ;每 10 0g干物质含维生素B12 0 92 7mg ,维生素A6 7mg。     

Aspergillus flavus-secreted proteins during an in vivo fungal-cotton carpel tissue interaction

Cotton bolls (Gossypium hirsutum) were inoculated with Aspergillus flavus to investigate extracellular hydrolases produced during infection. Fungal proteins from the infection site were isolated and analyzed by SDS-PAGE. Protein bands were excised and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We identified several proteins including an exoglucanase 1 precursor (AFL2G_03805), a hypothetical protein similar to rhamnogalacturonan lyase A (AFL2G_05136), and a hypothetical protein similar to pectate lyase A (AFL2G_05954). We also matched three peptides to an oryzin precursor protein (AFL2G_01995). Our findings support the conclusion that glucanase, pectinolytic, and proteolytic proteins are important for fungal maceration of cotton carpel tissue during infection.     

麝香百合花蕾组织原位杂交体系的建立

本研究以麝香百合未开放的花蕾为实验材料,以百合花发育相关的B功能基因LLGLO1的特异片段为探针,研究了花蕾切离时间对RNA结构完整性的影响,探讨了蛋白酶K消化浓度及时间对材料内蛋白质消化及材料结构完整性的影响.研究结果表明:花蕾离体1.5 h内RNA仍然保存完整,花蕾离体2hRNA开始降解,因此,花蕾取材后应在1.5...     

Development of a sensitive ELISA using three monoclonal antibodies against lipopolysaccharides to detect <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv. <Emphasis Type="Italic">vesicatoria</Emphasis>, the causal agent of bacterial spot of tomato and pepper

Bacterial spot, caused by Xanthomonas campestris pv. vesicatoria (Doidge 1920) Dye 1978 (Xcv), is responsible for severe production losses in tomato and pepper. Three specific monoclonal antibodies (MABs), 7AH10, 5HB3, and 4AD2, which are reactive to lipopolysaccharides of the bacteria, were tested in three kinds of enzyme-linked immunosorbent assays (ELISAs). The most sensitive ELISA was a competitive one able to detect populations of Xcv as low as 10³–10⁴cfu/ml. Bacterial growth in artificially inoculated tomato and pepper plants could be successfully monitored, and assays on field-collected samples reconfirmed the diagnostic utility of the MABs. Studies on the accessibility of the MABs to their lipopolysaccharide epitopes confirmed that sample preparation can be improved to further increase the sensitivity of the assay. Immunoblotting of differential extracts of the bacterial cells and immunoelectron microscopy demonstrated that the epitopes were present throughout the cell wall and involved in complexes that can be loosened through the action of proteinase K or lysozyme.     

Interaction of Cry1Ac toxin (Bacillus thuringiensis) and proteinase inhibitors on the growth, development, and midgut proteinase activities of the bollworm, Helicoverpa zea

Potential resistance development to Bt cotton in certain lepidopterans has prompted research to develop strategies that will preserve this environmental-friendly biotechnology. Proteinase inhibitors are potential candidates for enhancing Bt toxicity against lepidopteran pests and for expanding the spectrum of control for other insects. Interactions of Bt toxin from Bacillus thuringiensis and proteinase inhibitors were investigated by monitoring growth, development, and gut proteinase activities of the bollworm, Helicoverpa zea. Several proteinase inhibitors were combined with Bt protoxin Cry1Ac in artificial diet and fed to newly molted 3rd-instar bollworm larvae to determine effects on larval body weight and length, pupation progress, and mortality rate. Major midgut proteinase activities, including caseinase, tryptic, and chymotrypsin activities, were examined after treatment. A concentration of Bt at a level causing minimal mortality (<10%), was mixed with the following proteinase inhibitors: benzamidine, phenylmethylsulfonyl fluoride (PMSF), and N-α-tosyl-l-lysine chloromethyl ketone (TLCK). When compared with controls, the synergistic effect of Bt toxin and proteinase inhibitors caused significant decreases in mean larval weight and length over time. Midgut samples tested against the substrates azocasein, α-benzoyl-dl-arginine-p-nitroanilide (BApNA), and N-succinyl-alanine-alanine-proline-phenylalanine-p-nitroanilide (SAAPFpNA) showed significant decreases in the protease activity of larvae fed Bt plus inhibitor versus control. Interaction of Bt and proteinase inhibitors significantly retarded larval growth and resulted in developmental delay and up to 20% mortality.