Proteinase Inhibitors in Plant Seed

Three different types of proteinase inhibitors, I, II and III, were fractionated from Japanese radish seed by repeated column chromatographies on SE- and CM-cellulose. The finally purified preparation of inhibitor III was found to be homogeneous by both chromatographic and electrophoretic analyses. All three of them strongly and stoichiometrically inhibited trypsin whereas they showed weak inhibition on other proteinases, such as chymotrypsin, Nagarse and Pronase. From nitrogen content and ultraviolet absorption spectra, each of the inhibitors I and III was confirmed to be a protein. The molecular weights of inhibitors I and III were calculated to be 8000 and 12,000, respectively. These inhibitors were stable at temperatures above 90°C in an acidic pH.     

Proteinase Inhibitors in Plant Seeds

The proteinase inhibitors I (R-I) and III (R-III) isolated from Japanese radish seed were characterized in terms of their N-terminal amino acids, amino acid composition and reacting groups. The amino acid composition of two proteins differed from each other, while histidine, methionine and tryptophan contents were all low. N-Terminal amino acids of these inhibitors determined by Edman degradation were the same; valine.

By modifying free amino groups in the inhibitors with trinitrobenzenesulfonic acid, R-III was greatly inactivated in proportion to the modification of amino groups, but the activity of R-I was not affected.

However, modification of arginyl residues of R-I by cyclohexanedione reduced its activity. These results indicate that R-I is an arginine-type and R-III is a lysine-type inhibitor.     

植物的叶绿体基因组

对植物叶绿体基因组的特征,叶绿体编码基因,叶绿体基因表达调控以及叶绿体基因转化等内容进行了介绍和评述。     

植物天冬氨酸蛋白酶的研究进展

天冬氨酸蛋白酶是四大类蛋白水解酶之一,广泛存在于多种生物中,参与了很多重要的生理过程。相对于其他生物而言,对植物天冬氨酸蛋白酶的研究相对滞后。自20世纪末以来,这一领域的工作取得了重大进展。经典的植物天冬氨酸蛋白酶除了具有保守的蛋白酶结构域外还有一段植物特有的插入片段;在动植物分离之后,植物天冬氨酸蛋白酶基因家族进行了大规模的扩增;该类蛋白酶在植物的整个生长发育过程中发挥重要的功能,尤其是胁迫反应、有性生殖、衰老和程序性死亡以及蛋白质的加工和降解。对近些年植物天冬氨酸蛋白酶的研究进展进行综述,并对其未来的发展进行展望。     

Proteinase Inhibitor-inducing Factor in Plant Leaves: A Phylogenetic Survey

Thirty-nine plant species representing 20 families from the four major divisions of plants were surveyed for the presence of proteinase inhibitor-inducing factor activity in leaves or other tissues. Tissue juices were assayed for their capacity to induce accumulation of proteinase inhibitor I in excised tomato (Lycopersico esculentum) leaves. In tissues of only 2 of the 39 species was proteinase inhibitor-inducing factor-like activity not found. The activity was absent in cabbage leaves and celery stalks. Fruiting bodies from one of three fungi genera assayed contained exceptionally large quantities of proteinase inhibitor-inducing factor-like activity. Extracts from Agraricus campestris fruiting bodies contained over 20 times more activity than tomato leaf juice. The survey confirms that substances with proteinase inhibitor-inducing factor-like activity are widespread in the plant kingdom.     

叶绿体基因工程：一种植物生物技术的新方法

以叶绿体转化为主的叶绿体基因工程,与传统的基因工程技术细胞核转化相比,在外源基因表达水平和转基因植物安全性等方面有明显的优势, 尤其是在控制转基因沉默和遗传稳定性方面,可以互补核转化带来的局限性。因此,叶绿体基因工程是一种很具有发展前景的植物转基因技术,并在未来工农业生物技术领域发挥重要作用。本文着重在叶绿体转化技术主要特点,应用领域及其未来的发展前景等方面进行了简单评述。     

植物基因工程新途径：叶绿体转化

在植物基因工程研究中,叶绿体是继核转化之后又一新的遗传转化和表达受体,叶绿体转化体系具有可同时进行多基因转化,表达原核性,超量表达,后代遗传稳定,定点整合,不会产生基因沉默及母性遗传和安全性好等特点,本文着重介绍叶绿体转化体系的特点,国内外研究动态,存在的问题及未来发展方向。     

Plant Proteinase Inhibitors as Multifunctional Proteins (Review)

Data in the literature on plant proteinase inhibitors as multifunctional proteins are reviewed. In addition to the direct inhibitory effect on enzymes, these proteins may function in other processes, particularly under biotic and environmentally stressful conditions. A special section discusses the relationships of plant proteinase inhibitors and storage proteins.     

叶绿体遗传转化：植物导入外源基因的新途径

叶绿体转化系统,独立于传统的核转化,为植物导入外源基因提供了新途径,它有如下优点：超量表达目的的基因;以定点整合方式导入外源基因从而消除了位置效应及基因沉默;具有原核表达方式,能以多 反子的形式表达多个基因;母系遗传方式可防止基因扩散;基因产物区域化并能提供适于某些产物发挥功能的小环境等。随着这项技术在越来越多的领域发挥作用,其优势性逐渐得到认同。本文着重对此技术的特点,发展及应用作一综述。     

叶绿体遗传转化：植物导入外源基因的新途径

叶绿体转化系统,独立于传统的核转化,为植物导入外源基因提供了新途径。它有如下优点：超量表达目的基因;以定点整合方式导入外源基因从而消除了位置效应及基因沉默;具原核表达方式,能以多顺反子的形式表达多个基因;母系遗传方式可防止基因扩散;基因产物区域化并能提供适于某些产物发挥功能的小环境等。随着这项技术在越来越多的领域发挥作用,其优越性逐渐得到认同。本文着重对此技术的特点、发展及应用作一综述。     

植物蛋白酶抑制剂在植物抗虫与抗病中的作用

综述了植物蛋白酶抑制剂抗虫与抗病作用的研究进展.蛋白酶抑制剂广泛存在于植物体内,与植物抗虫抗病密切相关.植物蛋白酶抑制剂能抑制昆虫肠道蛋白酶,使昆虫生长发育缓慢,甚至死亡.但取食蛋白酶抑制剂后,昆虫能迅速分泌对抑制剂不敏感的蛋白酶,而使蛋白酶抑制剂无效.食物蛋白的含量和质量也影响植物蛋白酶抑制剂的抗虫效果.病原菌的感染能诱导植物产生蛋白酶抑制剂,诱导产生的蛋白酶抑制剂能抑制病原菌的生长.     

半胱氨酸蛋白酶在植物细胞程序性死亡中的作用

介绍了参与执行与控制植物细胞程序性死亡（PCD）的半胱氨酸蛋白酶的研究进展。     

高等植物叶绿体基因组转化的应用

叶绿体基因组转化技术由于其独特的优越性,现已成为植物基因工程的研究热点。本文简单介绍了叶绿体基因组转化技术的原理和方法;并重点综述了该技术在基础研究和实践中的应用。这些应用主要包括利用叶绿体基因组转化技术进行Rubisco的组装,叶绿体基因结构、转录、翻译和RNA编辑等研究;利用叶绿体作为生物反应器生产人生长激素、霍乱毒素抗体、聚羟基丁酸脂和生物弹性蛋白等;获得抗虫、抗病、抗除草剂和耐旱的转基因植物;以及降低转基因植物的外源基因扩散等。     

蛋白水解酶活力测定新方法

蛋白水解酶活力测定新方法周慧,鲁治斌,齐杰,李惟（吉林大学分子生学系．长春１３００２３）Ｇ．Ｆ．Ｂｉｃｋｅｒｓｔａｆｆ（Ｄｅｐｔ．ｏｆＢｉｏｌｏｇｙ,ＰａｉｓｌｅｙＵｎｉｖ,Ｓｃｏｔｌａｎｄ,Ｕ．Ｋ）本文研究了一种测定蛋白水解酶（Ｐｒｏｔｅｉｎａｓｅ...     

In-silico comparative study of inhibitory mechanism of Plant Serine Proteinase Inhibitors

The nematodes like root-knot and cyst are plant-parasitic pest found in horticultural and agricultural crops. They do damages in the roots of plants as a result losses million tons of production. High cost of nematicides and environment safety concern has necessitated finding of some alternative methods. Under Integrated Pest Management (IPM) such problems are solving significantly by means of target gene inhibition, agrobacterium mediated transformation etc. One of this strategy use Plant Proteinase Inhibitors (PIs) gene which are used to control the proteolysis mechanism of Pest by inhibiting gut Serine Proteinase (SP). Present work investigates the utility of computer aided methods to study the mechanism of Protein-Protein interactions and thereby inhibition of Serine Proteinase by PIs. Hence 3D models of Serine Proteinase as well as Serine Proteinase Inhibitors (SPIs) generated using homology modeling. Validations of constructed models have been done by PROCHECK, VERIFY3D, ERRAT and PROSA. Prediction of Protein interacting surface patches and site specific protein docking was performed by using ZDOCK Server. Backbone refinement of output protein complexes was executed in Fiber Dock server. Interaction study between SP and SPIs complexes shows their comparative inhibition efficacy, measured in terms of number of hydrogen bonds, Van dar wall attraction and docking energy. This work reported that Vigna marina and Phaseolus oligospermus are having better inhibition efficiency in comparison to other inhibitors.     

Changes in Chloroplast Ultrastructure in Pssu-ipt Tobacco During Plant Ontogeny

Changes in chloroplast ultrastructure and total content of endogenous cytokinins (CK) were studied during different phases of plant development in transgenic Pssu-ipt tobacco (Nicotiana tabacum L. cv. Petit Havana SR1). Permanent overproduction of CK was found in both rooted (SE) and grafted (G) Pssu-ipt plants in all phases of plant development with the peak in vegetative and flowering phase in the latter ones. No such a correlation was observed in SE on the contrary to control non-transgenic plants (SR1) and grafts (SRG), which showed also CK increase at juvenile and flowering phases. No significant differences in parameters of chloroplast ultrastructure, such as length of chloroplast, starch content, granum width, and number of thylakoids per granum, were proved between chloroplasts from young mature leaves of control and transgenic tobacco during plant ontogeny. Nevertheless, several anomalies in the ultrastructure of cell organelles were found in Pssu-ipt tobacco. Amoeboid shape of chloroplasts was often observed in connection with tubular clusters resembling peripheral reticulum. The distinct crystalline structures located in chloroplasts might be formed by LHC protein aggregates. Smaller crystals of unknown composition were found also in mitochondria. Numerous crystalline cores were present in peroxisomes. The alterations might be the result of imbalance of phytohormone content, degradation effect of CK overproduction, or the example of acclimation to permanent stress.     

Chloroplast Biogenesis Controlled by DELLA-TOC159 Interaction in Early Plant Development

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