Effects of Some Metal Ions on the Activity of Polyphenol Oxidase from Potato

以马铃薯多酚氧化酶为对象,研究金属离子对该酶活性的影响.实验结果表明,lI+、k+、bA2+和Mg2+对酶活力几乎没有影响,CA2+和nA+对酶活力有微弱的抑制作用,Cu2+则表现出较强烈的抑制作用,其IC50为0.248 MMOl/l.Al3+、fE3+、Cd2+、CO2+、Mn2+和zn2+则对马铃薯多酚氧化酶有不同程度的激活作用.本研究为探讨多酚氧化酶的催化活性和催化机理提供理论基础.In this paper,we studied the effects of some metal ions on the activity of polyphenol oxidase purified from potato.The results showed that Li+,K+,Ba2+ and Mg2+ had no effects on the enzyme activity.Ca2+ and Na+ showed a slight inhibition.Cu2+ could strongly inhibit the enzyme and the IC50 value was estimated to be 0.248 mmol/L.Al3+,Fe3+,Cd2+,Co2+,Mn2+ and Zn2+ activated the activity of polyphenol oxidase.This paper laid the foundation for the studies of the enzyme activity,catalytic mechanism of polyphenol oxidase.国家自然科学基金(30570408);福建省重点科技项目(2007N0051

Study on the Relationship Between α-Tubulin Gene and Cytoplamic Male Sterility (CMS) in Maize

采用两个核背景(Mo17,77)的同核异质、同质异核细胞质雄性不育系及正常品系为材料,以合成的α 微管蛋白基因片段为探针,对玉米细胞质雄性不育系转育前后的mRNA进行Northern杂交分析,首次直接从转录水平上比较了玉米细胞质雄性不育系在败育前后α 微管蛋白基因转录量的差异.结果表明,玉米细胞质雄性不育系α 微管蛋白基因在败育前后的转录量存在着明显的差异,败育前的相对转录量大于败育后的相对转录量,证明了α 微管蛋白基因在花粉发育中起着重要作用,与玉米细胞质雄性不育性密切相关.10 lines of maize used in the study, which are normal lines and cytoplasmic male sterile lins, belong to two types of nuclear backgroung and four types of cytoplasm. αtubulin gene fragment was used as the probe, which hybrid with RNA from pollen of normal stage and sterile stage respectively. The results indicated that there was distinct difference between normal stage and sterile stage of pollen in the 10 lines of maize in Northern blotting, which demonstrated thatαtubulin gene played an important role in the development of the pollen, and was closely related to CMS in maize.福建省青年科技项目资助(2001J033

红树植物耐盐基因转化烟草及耐盐品系的培育

从耐盐性强的红树植物白骨壤(Avicennia marina)中分离出的耐盐基因CSRG1,构建了pGAM189/CSRG1转基因载体,以烟草嫩叶为外植体,通过农杆菌介导的叶盘转化法将CSRG1基因及GUS基因,Kmr基因和Hygr基因转入烟草基因组中.转化50个外植体,经过50 mg/L潮霉素和150mg/L卡那霉素抗性筛选共获得了13个稳定抗性株系.通过PCR扩增检测、southern blot分析和GUS基因活性检测,结果表明,最终获得的11个转基因品系(基因转化频率为22％)中,CSRG1基因整合到烟草的染色体DNA上.Northern blot分析结果表明,CSRG1基因在转基因植株中获得表达.耐盐性测定和光合速率测定结果表明,转基因植株在盐分提高到2％NaCl和全海水(盐度为24)配置的MS培养基中,成活率保持在80％-90％,株高增长20％-40％,CSRG1基因的表达产物及形成的生理代谢途径确实可使烟草获得较高的耐盐性,同时这种耐盐性不仅针对钠离子胁迫,而且对于各种离子的综合盐胁迫都具有耐受性

GH37合金经激光表面熔凝后的组织与强度

本文研究了 GH37合金经连续 CO_2激光束辐照及补充热处理后的显微组织特点,和激光局部熔凝以及施加不同的后续热处理对热作用区显微硬度、700℃下的旋转弯曲疲劳、800℃下的拉伸及持久等力学性能的影响.结果表明,该合金经激光熔凝后,必须重新调整热作用区的组织状态使晶界碳化物晶内γ′相合适析出,以及尽量减少熔区枝晶间的元素偏析和消除辐照后的残余热应力等,才能使力学性能恢复到满意的指标。试验表明,适于本合金特点的处理工艺为:预热辐照,1050℃,4h,空冷;800℃,16h,空冷

Study on mutation breeding of banana buds in vitro Ⅳ: Bio-chemical analysis to 'Zhangjiao No. 8' strain

本文用60COγ射线对“台湾北蕉”(Musa AAA Group Cavendish)辐照诱变选育的“漳蕉8号”株系抗损伤相关酶的生化指标和过氧化物酶同工酶进行分析,结果表明,“漳蕉8号”株系对60COγ射线造成的损伤已完成修复,其优良性状可稳定遗传。Treated with irradiation of 60Coγ ray, a new strain 'Zhangjiao No.8' was developed from 'Musa AAA Group Cavendish'. The bio-chemical indexes corresponding to anti-injury and POD isoenzyme of 'Zhangjiao No.8' were analyzed. The results showed that 'Zhangjiao No.8' strain had recovered from the irradiation injury and the excellent traits could be inherited stably.漳州市科技计划项目(Z9315

GH37合金表面激光熔凝后的显微组织

本文采用1KW横流CO_2激光器研究了在不同激光熔凝和后续热处理条件下GH37合金表层的显微组织特征,为激光快速熔凝技术在沉淀硬化型高温合金中的应用提供了一定的试验依据

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel