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141.
Chilo suppressalis is a key constraint on production of rice. The current research was conducted to study the types of digestive proteases in the larval midgut of C. suppressalis. It was found that activity of total digestive proteases increased from the first to the fifth larval instars, which showed different nutritional requirements. Four types of proteinases and two types of exopeptidase were identified so that their activities from the highest to the lowest activities is trypsin‐like, chymotrypsin‐like and elastase for proteinases, and amino and carboxypeptidases for exopeptidases. Meanwhile, just one type of cysteine protease, cathepsin D, was determined in the fourth and fifth instar larvae. The optimal pH for activity of total protease was found to be pH 9–10 and optimal temperature was observed to be 35–40°C, where there was the highest proteolytic activity. Some specific inhibitors of proteases including PMSF, TLCK, TPCK, DTT, E‐64, cystatin, phenanthroline and EDTA were used to confirm the types of proteases in the midgut of C. suppressalis.  相似文献   
142.
Abstract

To investigate interaction between proteinaceous extracts of three Iranian wheat cultivars and digestive enzymes of Sunn pest, a population of adult insects was collected in summer from a wheat field located in Borkhar Region, Isfahan, Iran. Seed proteins were extracted by 0.15?M NaCl solution and partially purified using ammonium sulphate. Spectrophotometric assays were implemented to determine enzyme activities. Results indicated cultivar- and dose-dependent efficacy of seed protein extracts. Inhibition percentages of α-amylase, α-glucosidase, β-glucosidase and proteolytic activities at concentration of 32?μg/mL and saturation percentage of 70% ammonium sulphate were 54, 37, 25 and 59% by Hamoon, 16, 28, 18 and 19% by Karkheh and 15, 16, 15 and 23% by Dena, respectively. Zymography also confirmed the effect of inhibitors on α-amylase activity. Among wheat cultivars, Hamoon has the highest biological activity against Sunn pest major digestive enzymes and could contribute towards the development of new insect pest control strategies.  相似文献   
143.
The efficacy of a new virulent Metarhizium anisopliae variety (M. anisopliae var. dcjhyium, DQ288247) obtained from Odontotermes formosanus in China was evaluated against the subterranean termite, O. formosanus, in the laboratory. The new variety was compared with four other virulent M. anisopliae isolates and was found to be highly infectious and virulent against termites. M. anisopliae var. dcjhyium could cause approximately 100% mortality of termites 3 days post-inoculation in the concentration of 3x10(8) conidia/ml. There were also differences in relative hyhal growth and isoenzymes. M. anisopliae var. dcjhyium showed a different isoenzyme band pattern from the four isolates of M. anisopliae (AB027337, AB099510, AB099941 and AF280631). The phylogenetic tree of the 18S rDNA sequences revealed the taxonomic and evolutionary position of M. anisopliae var. dcjhyium. M. anisopliae var. dcjhyium and four isolates of M. anisopliae formed a monophyletic group, supported by a 99% bootstrap value. M. anisopliae var. dcjhyium formed a distinct variety, which had a special characterization of unique bands of isoenzyme, high virulence and low repellency against termites when compared with four other isolates of M. anisopliae.  相似文献   
144.
目的通过对AB、LF、ST(short tail,本地短尾群)三个封闭群斑马鱼的研究比较,建立封闭群斑马鱼的遗传生化标记。方法依照国标GB/T14927.1-2008的遗传操作规程优化实验条件,对三种群斑马鱼的7个遗传生化位点进行研究,以得到其遗传生化图谱。结果6-磷酸葡萄糖脱氢酶(Gpd)、过氧化氢酶(Ce)、苹果酸脱氢酶(Mod)、葡萄糖磷酸异构酶(Gpi)、酯酶(ES)位点表现出多态性。对三种群多态性位点进行卡方分析,Gpd、Gpi位点群间差异显著(P〈0.01),Ce、Mod有群间差异(P〈0.05)。碱性磷酸酶(AKP)、乳酸脱氢酶(LDH)位点,各品系谱带较一致,未见同工酶多态性。结论Gpd、Ce、Mod、Gpi、ES可作为3种封闭群斑马鱼群间评价的生化标记,通过进一步研究,可建立封闭群斑马鱼的遗传标准。  相似文献   
145.
目的通过研究对RR-B、RW-H、BY-F三个近交系和非选育剑尾鱼的研究比较,建立近交系剑尾鱼的遗传生化标记检测技术。方法依照国标GB/T14927.1-2008的遗传操作规程优化实验条件,对三个近交品系及非选育群剑尾鱼的不同组织的6个遗传生化位点进行研究,以得到其遗传生化图谱。结果在6个生化位点中,同一品系剑尾鱼同工酶存在组织特异性,多数同工酶在肝中活性较强。同一生化位点在不同品系间存在差异。RR-B系在葡萄糖磷酸异构酶(Gpi)、6-磷酸葡萄糖脱氢酶(Gpd)位点表现出特异性条带,RW-H系在过氧化氢酶(Ce)位点表现出特异性条带。同一生化位点在各品系内表现较为一致,而在非选育剑尾鱼中在上述三个生化位点表现出多态性。在酯酶(ES)、碱性磷酸酶(AKP)、乳酸脱氢酶(LDH)位点,各品系谱带不易区分其差异。结论建立了剑尾鱼近交系生化标记检测技术,可望用于近交系剑尾鱼的遗传质量监测。  相似文献   
146.
ABSTRACT We obtained isoenzyme patterns by polyacrylamide gradient gel electrophoresis (PGGE) of water-soluble protein fractions prepared from trophozoites of 11 axenic G. lamblia strains. The strains were isolated from animals and humans (both symptomatic and asymptomatic) from various geographic locations. Isoenzymes were also separated by isoelectric focusing. Of 12 enzymes attempted, eight exhibited well-defined and reproducible isoenzyme patterns by PGGE, based on which the strains were grouped into four zymodemes. Although the 11 strains were grouped into four zymodemes based on PGGE, no correlation between zymodeme and the known characteristics of the strains existed. Thus, a high degree of characteristic sharing appears to occur among genetically different G. lamblia strains.  相似文献   
147.
Cassia siamea is a nonedible legume belonging to Fabaceae. The seed of C. siamea contains ~16% of protein. The study reports the biochemical characterization of purified novel serine protease inhibitor from seeds of C. siamea, aimed with assessing the anti-inflammatory activity. The seed extract was subjected to ammonium sulfate precipitation followed by fast protein liquid chromatography (FPLC)-anion exchange chromatography and affinity-chromatography to obtain a relative pure protease inhibitor. Thirty-fivefold purification with the specific activity of 250 U/mg of trypsin inhibitory unit was obtained. The characterization of protease inhibitor for optimum temperature, pH, and metal ions were measured using N-α-benzoyl-DL-arginine-p-nitroanilide (BAPNA) assay and casein zymogram. The C. siamea trypsin inhibitor (CsTI) has a relative molecular mass of 25.540 kDa. Purified CsTI and Dolichos biflorus were tested for anti-inflammatory efficacy against A549 and RAW264.7 cell lines. The inhibitory activity of both purified inhibitors are comparable and are potent toward anti-inflammatory activity. The purified inhibitor shows to be a promising candidate as anti-inflammatory agent by targeting the serine proteases.  相似文献   
148.
Abstract Two flagellates of the family trypanosomatidae were isolated from the fruits of Lycopersicon esculentum (tomato) and Annona cherimolia (cherimoya) in the southeastern region of Spain. The isolates were characterized by isoenzyme analysis using nine different isoenzymes and by analysis of kinetoplast DNA (kDNA) restriction fragment length polymorphism using four different restriction endonucleases. Most of the isoenzymes were unable to distinguish between the two fruit isolates, while they were all able to distinguish these two from four other Phytomonas isolates, three of which were from laticiferous plants i.e. Euphorbia characias E. hirta and E. hyssopifolia , and one was a phloem-restricted isolate associated with Hartrot disease. Only the enzyme Superoxide dismutase was able to differentiate between the two fruit isolates. Electrophoretic and restriction endonuclease analysis of kDNA minicircles, using four restriction enzymes, showed similar if not identical restriction cleavage patterns of the minicircles of the two isolates from fruits, while the patterns were different for the other isolates. These results confirm the hypothesis that the two isolates from fruits constitute a group of trypanosomatids that are the same or closely related and that this group can parasitize more than one host plant.  相似文献   
149.
Oil palm (Elaeis guineensis Jacq.) plays an important economic role in some countries of Southeast Asia like Indonesia, which is the world’s second producer of palm and palm kernel oil. The quality improvement of planting material needs a better understanding of the genetic relationships between genotypes from different populations used in the breeding programmes. In this study, 48 parents, representative of four populations used in Indonesian Oil Palm Research Institute (IOPRI) breeding programmes, were analysed with five selected AFLP primer pairs and four isoenzymatic systems. One hundred and fifty eight scorable band levels were generated of which 96 (61%) were polymorphic. AFLP allowed us to identify off–type descendants which were excluded from analysis. The use of unbiased Rogers distance clearly separated the four studied populations. The Neighbor-Joining method re-groups two African populations which are known as originating from different regions. Nevertheless, the variability revealed is in accordance with oil palm breeders’ knowledge. The results obtained with AFLP showed that the crosses among the African sub-population, which is excluded in oil palm reciprocal recurrent selection (RRS) breeding programmes, may be more interesting than the crosses between the African and the Deli populations. Received: 9 August 1999 / Accepted: 28 February 2000  相似文献   
150.
C. Gietl  F. Lottspeich  B. Hock 《Planta》1986,169(4):555-558
The comparison of mitochondrial and glyoxysomal malate dehydrogenase (EC 1.1.1.37) from cotyledons of germinating watermelon (Citrullus vulgaris Schrad., cv. Kleckey's Sweet No. 6) by means of serological methods and peptide patterns revealed a high degree of homology. The N-terminal sequence analysis yielded a distinct presequence of eight or nine amino-acid residues, respectively, which is followed by an almost identical stretch of at least 20 amino-acid residues. A very similar domain has been recognized for mitochondrial malate dehydrogenase from porcine heart and yeast, and for Escherichia coli malate dehydrogenase.Abbreviations gMDH glyoxysomal malate dehydrogenase - mMDH mitochondrial malate dehydrogenase - SDS sodium dodecyl sulfate  相似文献   
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