甲基磺酸乙酯对水稻萌发种子的生理效应

用不同浓度的EMS处理预浸泡的水稻种子,对水稻萌发种子细胞内呼吸代谢有明显的影响。低剂量的EMS刺激呼吸,提高细胞色素氧化酶和α-淀粉酶活性,从而促进了种子萌发和幼苗生长。较高剂量的EMS抑制呼吸以及与之有关的细胞色素氧化酶、α-淀粉酶和过氧化物酶等多种酶活性,科子发芽势和发芽率、幼苗生长高度和根系活力也随之下降。实验结果表明,EMS对细胞呼吸以及上述三种酶类活性的影响是导致水稻种子发芽率和幼苗生长高度、根系活力改变的重要生理原因。     

谷子耐盐系的几种同工酶的变化及外源ABA对它们的影响

对谷子细胞变异系的过氧化物酶,细胞色素氧化酶和脂酶同工酶的分析表明：耐盐系在无盐胁迫条件下过氧化物酶同工酶的总酶活性高于对照系,其各同工酶带的强度也与对照有明显差异;在ＮａＣｌ迫条件焉耐盐系中个别原有的酶带消失。细胞色素氧化活性与过氧化物酶同工酶的活性变化情况类似,均与对照有明显差异。     

渗透胁迫对小麦幼苗根系呼吸的影响

用PEG—6000调节培养液的渗透势,研究了渗透胁迫对小麦幼苗根系呼吸作用的影响。在-0.5 MPa的溶液中根总呼吸强度显著降低,不同苗龄根的反应差异明显;随胁迫加强呼吸强度随之降低;根系ATP含量减少。在胁迫初期呼吸废物对呼吸强度的降低无补偿作用,而在后期(72 h后)则可提高呼吸强度。 中度水分胁迫下,HMP支路活性上升,EMP-TCAO途径活性降低;抗氰呼吸活性增大,而对氰敏感的系统活性减低;细胞色素氧化酶活性显著低于对照。     

硫酸二乙酯、叠氮化钠对水稻种子萌发、幼苗初期生长的影响

本文以水稻为材料,研究化学诱变剂dES、NaN_3对种子萌发及幼苗生长发育的影响。用不同浓度的dES、NaN_3处理预浸泡的水稻种子,测定种子的发芽率、发芽势、幼苗高度和根系活力,同时测定其呼吸强度和细胞色素氧化酶活性。结果表明,dES、NaN_3对水稻初期生长发育具有抑制作用。种子经化学诱变剂dES或NaN_3处理后,细胞呼吸强度和细胞色素氧化酶活性明显下降,种子发芽率、发芽势、幼苗生长高度和根系活力也不同程度地降低。诱变剂的剂量愈高,抑制愈强烈。由试验结果可知,化学诱变剂首先影响细胞的能量代谢活动,从而导致种子发芽率降低,幼苗生长迟缓,根系活力下降。     

水稻细胞质雄性不育系与保持系的呼吸途径比较

比较水稻细胞质雄性不育系珍汕97A及其保持系珍汕97B之幼穗、叶片和花药的呼吸代谢。结果表明：不育系花药的总呼吸速率、抗氰呼吸所占总呼吸比例和细胞色素氧化酶（COD）、苹果酸脱氢酶（MDH）和6－磷酸葡萄糖脱氢酶（6－PGDH）活性低于保持系;幼穗中则仅6－PGDH低于保持系;叶片间各指标均无差异。Na3PO4可抑制保持系的叶片和幼穗及不育系叶片总呼吸的30％,而仅能抑制不育系幼穗总呼吸的24％;丙二酸则抑制不育系与保持系的叶片和幼穗的总呼吸的70％。     

海水型呼吸窘迫综合征兔肺酶活性定位和图像分析

采用酶活性反应的图像分析和细胞化学技术,对兔海水型呼吸窘迫综合征(SW-RDS)肺酶活性的变化进行了研究。SW-RDS组肺碱性磷酸酶、5-核苷酸酶、对-硝基苯磷酸酶和细胞色素氧化酶活性明显下降,而胞嘧啶单核苷酸酶活性明显增强。这表明肺一些酶活性的改变是SW-RDS发病机理之一。     

水稻细胞质雄性不育系与保持系的呼吸途径比较

比较水稻细胞质雄性不育系珍汕９７Ａ及其保持系珍汕９７Ｂ之幼德、叶片和花药的呼吸代谢。结果表明：不育系花药的总呼吸速率、抗氰呼吸所占总呼吸比较和细胞色素氧化酶（ＣＯＤ）、苹果酸脱氢酶（ＭＤＨ）和６－磷酸葡萄糖脱氢酶（６－ＰＧＤＨ）活性低于保持系;幼穗中则仅６－ＰＧＤＨ低于保持系;叶片间各指标均无差异。Ｎａ３ＰＯ４可抑制保持系的叶片和幼穗及不育系叶片总呼吸的３０％,而仅能抑制不育系幼穗总呼吸的２４％;     

轻度水分胁迫的小麦幼苗中与呼吸有关的几种酶活性变化

轻度水分胁迫使小麦幼苗叶片呼吸升高时,叶中琥珀酸去氢酶和细胞色素氧化酶活性均明显升高;而同样胁迫使根呼吸下降时,根中这两种酶活性均明显下降。叶和根中ATP酶分解活性在胁迫下都明显升高。轻度水分胁迫使叶片过氧化氢酶活性升高。叶中有明显的乙醇酸氧化酶活性,抗旱品种的酶活性较高,胁迫使此酶活性降低。     

燕雀和麻雀代谢产热及消化道形态特征比较

于 2 0 0 3年 4～ 5月在黑龙江省齐齐哈尔市地区以 1 0只燕雀 (Fringillamontifringilla)和 9只麻雀(Passermontanus)的耗氧量、肝脏和肌肉的线粒体呼吸、肝脏和肌肉的细胞色素C氧化酶活性及消化道形态特征等为指标 ,探讨了燕雀和麻雀代谢产热及消化道形态的差异。燕雀的代谢率、肝脏和肌肉的线粒体呼吸及细胞色素C氧化酶活性均显著低于麻雀 ;而消化道总长度及小肠长度均明显高于麻雀。表明选择压力的不同塑造了燕雀和麻雀对环境的适应对策不同     

水稻细胞质雄性不育系及其保持系幼穗发育过程中的多胺代谢

在幼穗发育过程中,不育系和保持系幼穗多胺含量先剧降后稳定或略回升,精氨酸脱羧酶活性快速下降,而二胶和多胺氧化酶活性缓慢下降。从雌雄蕊形成期到花粉母细胞形成期,不育系的多胺含量和精氨酸脱羧酶活性明显低于保持系;不过,两系二胺氧化酶和多胺氧化酶活性却差别不大。外施D-Arg抑制两系Put合成,也抑制以Put为前体的Spd的合成;外施MGBG抑制Spd和Spm的合成;同时,D-Arg或MGBG对不育系花粉育性影响不大,但明显降低保持系花粉育性,D-Arg＋MGBG对花粉育性的降低效应更强;Put和pd＋Spm可抵消（或部分抵消）D-Arg和MGBG的降低效应。且Put＋Spd＋Spm能使不育系花粉的育性得以轻度恢复。     

模拟污水中氮、磷对水稻幼苗根系呼吸作用的影响

研究了模拟污水中不同浓度的Ｎ、Ｐ对水稻幼苗根系呼吸强度、细胞色素氧化酶、呼吸途径等的影响。结果表明,在总氮（ＮＴ）、总磷（ＰＴ）浓度分别小于４．２８ｍｍｏｌ／Ｌ、０．２ｍｍｏｌ／Ｌ时,呼吸速率、细胞色素氧化酶和呼吸商（ＲＱ）均随Ｎ、Ｐ浓度增大而增加,当超过这一浓度后,则随总氮总磷浓度上升而下降。总氮、总磷浓度分别小于４．２８ｍｍｏｌ／Ｌ、０．２ｍｍｏｌ／Ｌ时,磷酸戊糖途径（ＨＭＰ）随Ｎ、Ｐ浓度增加     

Changes in Terminal Respiratory Pathways of Bacillus subtilis During Germination, Outgrowth, and Vegetative Growth

The chemical and enzymatic properties of the cytochrome system in the particulate preparations obtained from dormant spores, germinated spores, young vegetative cells, and vegetative cells of Bacillus subtilis PCI219 were investigated. Difference spectra of particulate fractions from dormant spores of this strain suggested the presence of cytochromes a, a(3), b, c(+c(1)), and o. All of the cytochrome components were present in dormant spores and in germinated spores and vegetative cells at all stages which were investigated. Concentrations of cytochromes a, a(3), b, and c(+c(1)) increased during germination, outgrowth, and vegetative growth, but that of cytochrome o was highest in dormant spores. As the cytochrome components were reducible by reduced nicotinamide adenine dinucleotide (NADH), they were believed to be metabolically active. Difference spectra of whole-cell suspensions of dormant spores and vegetative cells were coincident with those of the particulate fractions. NADH oxidase and cytochrome c oxidase were present in dormant spores, germinated spores, and vegetative cells at all stages after germination, but succinate cytochrome c reductase was not present in dormant spores. Cytochrome c oxidase and succinate cytochrome c reductase activities increased with growth, but NADH oxidase activity was highest in germinated spores and lowest in vegetative cells. There was no striking difference between the effects of respiratory inhibitors on NADH oxidase in dormant spores and those on NADH oxidase in vegetative cells.     

肾缺血再灌流损伤过程中肾小管上皮细胞色素氧化酶活性变化及TAD防治作用的研究

本实验选用大鼠一侧肾切除,对侧肾缺血６０ｍｉｎ动物模型,用组织化学方法观察再灌流１５ｍｉｎ,２４ｈ髓质外带肾小管上皮细胞色素氧化酶活性的变化及还原型谷胱甘肽（ＴＡＤ）对它们的影响。结果发现６０ｍｉｎ肾缺血后再灌流可致细胞色素氧化酶活性呈进行性降低。给ＴＡＤ能一定程度地保护细胞色素氧化酶活性。提示氧自由基可能损害细胞色素氧化酶活性,细胞色素氧化酶活性降低在肾缺血再灌流损伤中可能起重要作用。     

不同营养方式对小球藻FACHB 484生长的影响及其非自养生长机理研究

系统研究了小球藻FACHB 484在含有葡萄糖的不同营养方式下的生长情况,并通过抑制试验探讨葡萄糖在小球藻FACHB 484光异养和兼养生长条件下所起的作用以及小球藻FACHB 484是否存在氧化呼吸系统的关键酶类。结果表明:小球藻FACHB 484可利用葡萄糖进行化能异养、光激活异养、光异养及兼养生长,其生长速率大小为:兼养光异养光激活异养化能异养光合自养。兼养培养的最大生物量和比生长速率分别是自养培养的8.6和3.4倍,其比生长速率接近于光合自养和光异养培养下的比生长速率之和。葡萄糖主要作为小球藻FACHB 484兼养和光异养培养的碳源,而能量主要源自光。小球藻FACHB 484存在氧化呼吸链代谢途径,其细胞中有琥珀酸脱氢酶和细胞色素氧化酶。       

Direct Budding from Explants in Young Panicle Culture of Some Monocotyls

In the young inflorescence (panicle) culture of 22 species of 6 genera, i.e. Oryza, Echino- chloa, Pennisetum, Setaria, Panicum and Musa, it was found that the young inflorescences budded directly from explants in 19 species of all 6 genera in the culture medium containing NAA and kinetin, but no 2,4-D. According to the frequency and the speed of direct spikelet budding (DSB), these species could be classified into four groups (Table l). The response of the young panicles in the first group (Cultivar rice, O. spontanea, Echinochloa and some interspecific hybrids) was very rapid in the 2,4-D free medium. Within a week, the young panicles of the first group distinctly sweelled then the buds began to develop from the spikelets after 15 days of inoculation. The frequency of DSP in this group was more than 70%. The response of the young panicles in the second group (O. perenis (512), O. officinalis (525) O. punctata (544), O. nivara (1050) and O. rufipogon Ï O. nivara (648) was not as rapid as that of the first group. A frequency of DSP around 20% was observed after 30 days of inoculation. The response of the young panicles in the third group) O. australiansis, Panicum maximum, Musa X paradisiaca (ABA) was rather tardy and slow, the frequency of DSP being less than 10%. The duration of DSP was more than one month. In the fourth group, the young panicles did not respond to the medium in this experiment. Besides the spikelet budding, sometimes adventitious bud could develop from the cutting place of the panicle axis usually the budding from the spikelets inhibited the growth of adventitious buds, but in this case the growth of adventitious bud could suppress the DSP. Some spikelets budded directly from the panicles of Setaria and Echinoshloa which were cultured in the same test tube, while the other spikelets of the same panicle were flowering. Calli were formed from some spikelets of Panicum and Oryza, while the others of the same panicle in the same test tube were budding.     

甲基磺酸乙酯对水稻花药离体培养效应的研究

本文以粳稻“105”、籼稻“华03”和“鄂早6号”为实验材料,研究了不同浓度化学诱变剂EMS处理对离体培养水稻花药中花粉细胞脱分化与再分化和培养初期花药呼吸作用的影响。结果表明,低浓度EMS能显著提高花药愈伤组织诱导率,高浓度EMS则有明显的抑制作用。EMS对培养初期花药呼吸作用的影响与花药愈伤组织诱导率之间存在明显的平行关系。     

A mechanism of respiratory control: studies with proteoliposomes containing cytochrome oxidase and bacteriorhodopsin

Both beef heart cytochrome oxidase and bacteriorhodopsin of Halobacterium halobium were reconstituted into liposomes by the sonication-cholate dialysis method. The proteoliposomes showed the respiratory control ratio of 4.2, and steady-state illumination of the vesicles lead to the 2.7-fold stimulation of the oxidase activity in the absence of uncouplers. The light-stimulated state 4 respiration increased with light intensity, but light had no effect on the oxidase activity that had been relieved by addition of uncouplers. Proteoliposomes with the photosensitive oxidase activity were also obtained when cytochrome oxidase vesicles were fused with bacteriorhodopsin vesicles in the presence of calcium chloride, and the extent of photoactivation was maximally 1.4-fold. The light-induced respiratory release was observed even in the presence of valinomycin or nigericin, indicating that the oxidase activity was sensitive to both the membrane potential and the pH gradient. We propose as a mechanism of the respiratory control that the process of proton transport to the reaction center for water formation is the rate limiting step for the cytochrome oxidase activity.     

Respiratory systems of the Bacillus cereus mother cell and forespore.

The respiratory systems of the mother cells and forespores of Bacillus cereus were compared throughout the maturation stages (III to VI) of sporulation. The results indicated that both cell compartments contain the same assortment of oxidoreductases and cytochromes. However membrane fractions from young forespores were clearly distinct from those of the mother cell, i.e., lower content of cytochrome aa3, lower cytochrome c oxidase activity, higher concentration of cytochrome o, and a lower sensitivity of the respiration to the inhibiting effect of cyanide. This suggests that the cyanide-resistant pathway contributes more importantly to forespore respiratory activity than to activity in the mother cell compartment. During the maturation stages, the forespore NADH oxidase activity declined faster than in the mother cells. Other activities studied decreased steadily in both cell compartments. These findings together with the analysis of the kinetics of NADH-dependent reduction of cytochromes in the mature spore membranes indicated an impairment of electron flow between NADH dehydrogenase and cytochrome b. This impairment could be overcome by the addition of menadione.     

Comparative Proteomic Analysis Reveals Nitrogen Fertilizer Increases Spikelet Number per Panicle in Rice by Repressing Protein Degradation and 14-3-3 Proteins

The spikelet number per panicle is established in the early stages of panicle development. Nitrogen fertilizer application before panicle initiation is known to increase spikelet number, which is one of the most important traits in rice productivity determination. However, the basic proteomic mechanism remains poorly understood. The present study shows that nitrogen fertilizer significantly increased spikelet number and grain yield in rice. Proteomic variations were further analyzed in young panicles at the secondary panicle branch initiation and spikelet meristem initiation under nitrogen fertilizer treatment. Proteomic analysis identified 63 proteins with significant differential accumulation in young panicles under nitrogen fertilizer treatment. Proteolysis represents the largest functional category, which suggests that protein degradation is an important pathway in the response to nitrogen fertilizer. Importantly, nitrogen fertilizer significantly reduced 14-3-3 proteins, which interact with key enzymes associated with carbon and nitrogen metabolism, and the rice FT homologue Hd3a. Real-time PCR revealed that Hd3a signaling is also repressed by nitrogen fertilizer in leaves. This study contributes to a better understanding of the regulation of nitrogen fertilizers in the flowering pathway leading to panicle development. The identification of novel genes provides new insight into the profound impacts of nitrogen fertilizer on panicle development in rice.