西葫芦离体雌核发育初期POD及其同工酶活性变化研究

以一代杂种碧珠为供体诱导西葫芦离体雌核发育,研究了离体雌核发育初期胚珠中过氧化物酶(POD)及其同工酶活性的变化规律.结果显示,西葫芦离体雌核发育初期即未受精胚珠接种后13 d内,胚珠中POD及其同工酶活性变化明显,其中总的过氧化物酶(POD)、NADH过氧化物酶(NADHPOD)、生长素过氧化物酶(IAAO)、谷胱甘肽过氧化物酶(GSH-Px)的活性呈上升趋势;细胞色素过氧化物酶(COX)、抗坏血酸过氧化物酶(ASP)的活性呈先下降后略升高的趋势.     

系统感染TMV诱导的番茄叶片过氧化物酶

番茄系统感染ＴＭＶ诱导叶片胞外蛋白量增加。叶片过氧化物酶活性升高，分析叶片总活力和叶胞外酶的活力表明，感病番茄过氧化物酶活力主要位于胞外。同工酶分析表明，番茄感染ＴＭＶ后叶片产生了新的过氧化物酶同工酶带，对比叶片胞外蛋白的ＰＡＧＥ图谱表明，一组主要蛋白带具过氧化物酶活力。ＳＤＳ—ＰＡＧＥ的过氧化物酶同工酶复性分析证明，番茄叶片过氧化物酶至少存在两种分子量。     

Differential structure and physiological response to canker challenge between ‘Meiwa’ kumquat and ‘Newhall’ navel orange with contrasting resistance

Asiatic citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most detrimental diseases affecting citrus production. ‘Meiwa’ kumquat (Fortunella crassifolia) and ‘Newhall’ navel orange (Citrus sinensis) are two genotypes with contrasting Xcc resistance. In the current study, efforts were made to perform pairwise comparison between them in terms of structural difference and biochemical response to Xcc attack. Pinprick inoculation demonstrated that ‘Meiwa’ had lower disease incidence rate and smaller lesion size, concurrent with significantly less bacterial number at the inoculation sites relative to ‘Newhall’. Microscopic observation demonstrated that stomatal density and size of ‘Meiwa’ were significantly smaller than ‘Newhall’. Stomatal apertures of ‘Meiwa’ were smaller than ‘Newhall’ measured at 2 h after their leaves were immersed in Xcc suspension, consistent with the bacteria number in the internal tissues counted at 4 d. Epicuticular wax content of ‘Meiwa’ was significantly higher than that of ‘Newhall’, while no difference in palisade and spongy tissue was observed between them. Enzymatic activity assay showed that after Xcc inoculation, ‘Meiwa’ exhibited significantly higher activities of catalase (CAT), peroxidase (POD) and phenylalanine ammonia-lyase (PAL) in comparison with ‘Newhall’ at most of the sampling time points. Our data showed that the two genotypes with contrasting Xcc resistance exhibited clear difference in the structure and physiological response, which may provide information to facilitate our understanding of Xcc resistance.     

蝴蝶和蝗虫肠道共生菌次生代谢产物的分离

采用分光光度计法测定低温处理后椰心叶甲啮小蜂（Tetrastichus brontispae）成虫体内3种保护酶活性的变化。结果表明,椰心叶甲啮小蜂成蜂受到低温胁迫后体内CAT、POD和SOD分别在10 ℃和-2 ℃出现两个高峰,酶活性总体水平高于对照。-2 ℃时,3个处理时间的CAT、POD和SOD活性最高,其中,CAT、SOD活性差异性显著。由于各种酶的特性不同,它们对低温应激处理时间的反应亦不同,SOD在处理12 h时酶活性最高,而CAT与POD在24 h时酶活性最高。     

种衣剂对玉米幼苗某些酶活性及苗体生长的影响

实验用三种种衣剂包衣玉米种子,研究了玉米幼苗中某些与植物抗逆代谢有关的酶活性变化。三种种衣剂均使超氧化物歧化酶、过氧化氢酶和过氧化物酶活性升高,苗体干鲜重增加。表明玉米种衣剂可通过调节玉米幼苗中某些酶的活性,增强植株的抗逆性。     

水杨酸对小麦愈伤组织CAT和POD同工酶的影响

分别用浓度为 5或 1 0 mg/ L的水杨酸处理河农 859小麦愈伤组织 ,发现它具有抑制 POD和 CAT活性以及小麦愈伤组织胚性细胞形成的作用 ,但 5mg/ L的水杨酸也诱导一种 POD出现     

白灵菇木质素降解酶系的检测及其染料脱色能力的研究

[目的]明确白灵菇(Pleurotus ferulae)分泌木质素过氧化物酶(LiP)、锰过氧化物酶(MnP)和漆酶(Laccase)的规律,以及白灵菇染料脱色的能力。[方法]利用紫外可见分光光度计,检测4种培养方式下白灵菇木质素降解酶活性,并在此基础上进行了白灵菇对5种染料的脱色研究。[结果]4种培养方式下,可以检测到MnP和Laccase的活性,但并未检测到LiP。添加Mn2+和2,6-二甲氧基苯酚(2,6-DMP)对MnP和Laccase的产生有抑制作用,而添加青杨木屑可以将MnP的活性提高1.28倍,将Laccase的活性提高3.75倍;白灵菇对中性红和活性黑2种染料的最大脱色率分别为87.12%和86.13%,对活性红和刚果红的最大脱色率分别为45.91%和32.28%,而对结晶紫几乎无脱色能力。[结论]白灵菇产Laccace活性要高于MnP;与脱色活性红、刚果红、结晶紫相比,白灵菇对中性红和活性黑2种染料的脱色更为彻底。     

大豆抗源抗SCN过程中POD酶动态分析

能动地大豆抗源抗孢囊线虫（ＳＣＮ）过程中过的氧化物酶（ＰＯＤ）活性和酶谱的变化研究,探讨了大豆抗源在抗病过程中是通过提高体内ＰＯＤ酶活性来抵御ＳＣＮ的侵染,抗源品种ＰＯＤ活性和酶谱呈动态变化。在侵染高峰期（３０￣３５ｄ）,高抗抗原体内ＰＯＤ酶活性最强,酶谱着色较深;而感病品种在侵染高峰期ＰＯＤ酶活性降至最低值,且一些酶带受损以至消失。另外,证实了ＰＯＤ酶在抗病过程中参与木质素的合成。抗病过程中酶活     

棉花雄性不育“三系”过氧化物酶同工酶等电聚焦电泳分析

通过等电聚焦电泳,在 pH4—6区间显示出棉花质核雄性不育系、保持系、恢复系在子叶、真叶、茎、花药等部位中共有20种不同的过氧化物酶同工酶带,其中有4条为这4种部位所共有。同时,叶片、茎、花药都各有其专一酶带。供试的“三系”在同一部位中均具有一些相同的基本酶带,相同系间差异较小,表现出它们有着某些基本一致的遗传背