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1.
Plant seeds store triacylglycerols in discrete organelles called oil bodies. An oil body preserves a matrix of triacylglycerols surrounded by a monolayer of phospholipids embedded with abundant structural proteins termed oleosins and probably some uninvestigated minor proteins of higher molecular mass. Three polypeptides of 27, 37, and 39 kDa (temporarily denominated as Sop1, Sop2, and Sop3) were regularly co-purified with seed oil bodies of sesame. Comparison of amino acid composition indicated that they were substantially less hydrophobic than the known oleosins, and thus should not be aggregated multimers of oleosins. The results of immuno-recognition to sesame proteins extracted from subcellular fractions of mature seeds, various tissues, and oil bodies purified from different stages of seed formation revealed that these three polypeptides were unique proteins gathered in oil bodies, accompanying oleosins and triacylglycerols, during the active assembly of the organelles in maturing seeds. Both in vivo and in intro, immunofluorescence labeling using secondary antibodies conjugated with FITC (fluorescein isothiocyanate) confirmed the localization of these three polypeptides in oil bodies.  相似文献   

2.
The oil bodies of plant seeds contain a triacylglycerol matrix surrounded by a monolayer of phospholipids embedded with alkaline proteins termed oleosins. Two distinct oleosins are present in the oil bodies of diverse angiosperms, and classified as high and low Mr isoforms according to their relative molecular masses in each species. In sesame oil bodies, besides the two ubiquitous oleosin isoforms (17 and 15 kDa), an additional minor oleosin (15.5 kDa) was revealed on Tricine SDS-PAGE. A full-length cDNA fragment was cloned, sequenced and deduced to be a putative oleosin of 15,446 Da. The gene was constructed in a fusion or non-fusion vector and then over-expressed with different efficiency in Escherichia coli. All three oleosins purified from sesame oil bodies were subjected to immunoassaying using antibodies raised against the over-expressed oleosin. The results confirmed that this gene encodes the sesame 15.5 kDa oleosin. Sequence comparisons with other known oleosins revealed that sesame 15.5 kDa oleosin does not represent a new oleosin isoform class but may have been derived through gene duplication and truncation of sesame 17 kDa oleosin, and possesses the minimal structure of the high Mr oleosin isoform. A conserved amphipathic alpha-helix is predicted in sesame 15.5 kDa oleosin, which may imply a potential biological function associated with this isoform.  相似文献   

3.
In seeds, the subcellular storage oil bodies have a matrix of oils (triacylglycerols) surrounded by a layer of phospholipids embedded with abundant structural proteins called oleosins. We used two maize (Zea mays L.) strains having diverse kernel (seed) oil contents to study the effects of varying the oil and oleosin contents on the structure of the oil bodies. Illinois High Oils (IHO, 15% w/w oils) and Illinois Low Oils (ILO, 0.5%) maize kernels were the products of breeding for diverse oil contents for about 100 generations. In both maize strains, although the genes for oil synthesis had apparently been modified drastically, the genes encoding oleosins appeared to be unaltered, as revealed by Southern blot analyses of the three oleosin genes and sodium dodecyl sulfate-polyacrylamide gel electrophoresis with immunoblotting of the oleosins. In addition, both strains contained the same three oleosin isoforms of a defined proportion, and both accumulated oils and oleosins coordinately. Oleosins in both strains were restricted to the oil bodies, as shown by analyses of the various subcellular fractions separated by sucrose-density-gradient centrifugation. Electron microscopy of the embryos and the isolated organelles revealed that the oil bodies in IHO were larger and had a spherical shape, whereas those in ILO were smaller and had irregular shapes. We conclude that in seeds, oleosin genes are expressed independent of the oil contents, and the size and shape of the oil bodies are dictated by the ratio of oils to oleosins synthesized during seed maturation. The extensive breeding for diverse oil contents has not altered the apparent mechanism of oil-body synthesis and the occurrence of hetero-dimer or -multimer of oleosin isoforms on the oil bodies.  相似文献   

4.
A papain-type cysteine endopeptidase with a molecular mass of 35 kDa for the mature enzyme, was purified from germinating castor bean (Ricinus communis L.) endosperm by virtue of its capacity to process the glyoxysomal malate dehydrogenase precursor protein to the mature subunit in vitro (C. Gietl et al., 1997, Plant Physiol 113: 863-871). The cDNA clones from endosperm of germinating seedlings and from developing seeds were isolated and sequence analysis revealed that a very similar or identical peptidase is synthesised in both tissues. Sequencing established a presequence for co-translational targeting into the endoplasmic reticulum, an N-terminal propeptide and a C-terminal KDEL motif for the castor bean cysteine endopeptidase precursor. The 45-kDa pro-enzyme stably present in isolated organelles was enzymatically active. Immunocytochemistry with antibodies raised against the purified cysteine endopeptidase revealed highly specific labelling of ricinosomes, organelles which co-purify with glyoxysomes from germinating Ricinus endosperm. The cysteine endopeptidase from castor bean endosperm, which represents a senescing tissue, is homologous to cysteine endopeptidases from other senescing tissues such as the cotyledons of germinating mung bean (Vigna mungo) and vetch (Vicia sativa), the seed pods of maturing French bean (Phaseolus vulgaris) and the flowers of daylily (Hemerocallis sp.).  相似文献   

5.
To investigate the potential anti-inflammatory effects of sesame oil, which is present in the injectable gold preparation Auromyose, the synthesis of tumour necrosis factor alpha (TNF-alpha), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) by in vitro stimulated blood cells was measured before, during and after 12 weeks of dietary supplementation with 18 g of sesame oil daily in 11 healthy male volunteers. Neither TNF-alpha, PGE2 nor LTB4 production levels showed statistically significant changes during the 12 weeks of dietary supplementation with sesame oil. These results do not suggest an anti-inflammatory effect of sesame oil as present in injectable gold preparations which are used in the treatment of rheumatoid arthritis.  相似文献   

6.
Sesame seed and sesame seed oil have been thought of as rare causes of food allergy, representing less than 1% of all food allergy cases. We now report nine cases of IgE-dependent allergy to sesame seed and/or sesame seed oil, six of which were diagnosed in 1995 alone. Our skin test results draw attention to the poor quality of a commercial sesame seed extract and the good sensitivity of skin prick tests made with a freshly prepared sesame seed flour extract. The diagnosis of this food allergy was established by double-blind oral provocation tests, with doses of sesame seed flour ranging from 100 mg to 10 g. Allergy to sesame seed oil was also demonstrated in some cases. The sensitivity of the Pharmacia Phadebas CAP System for the detection of sesame seed-specific IgE was only mediocre. We draw attention to the important use of sesame seed in modern cooking, a fact which may explain the growing frequency of this allergy. We underline the particular risk with sesame seed oil. Sesame seed should also be considered a cause of allergic reactions to drug products and cosmetics.  相似文献   

7.
Mechanism of Effect of Lanthanum Nitrate on Vigor of Aged Rice Seeds   总被引:2,自引:0,他引:2  
Seedsearlydegeneratedoragedbyun suitablecultivationorunstoragetechniquesmayresultindecreasingofseedvigorandofthecropsoutput,especiallyforrice.Rareearthsacceleratethegerminationandgrowthofthecrops ,suchasrice ,wheat,barley ,veg etablesandoilplants[1~ 3] .Thest…  相似文献   

8.
A bifunctional alpha-amylase/subtilisin inhibitor (RASI) was purified to electrophoretic homogeneity from rice (Oryza sativa L.) bran. Its molecular mass was 21 kDa by SDS-PAGE and its isoelectric point was 9.05. Purified RASI inhibited subtilisin Carlsberg strongly and inhibited alpha-amylase from germinating rice seeds weakly. It inhibited rice alpha-amylase more than barley alpha-amylase, and the inhibition of rice alpha-amylase was greater at higher pHs. RASI did not inhibit trypsin, chymotrypsin, cucumisin, or mammalian alpha-amylase. The RASI was in the outermost part of the rice grain and its subcellular site seemed to be aleurone particles in aleurone cells. SDS-PAGE and western blotting showed that RASI was synthesized in the late milky stage in developing seeds, and it remained fairly constant during the first 7 days of germination.  相似文献   

9.
OBJECTIVE: To develop a slow-release carboplatin formulation for intratumoral administration to cats. DESIGN: Preliminary study to analyze pharmacokinetic effects of purified sesame oil in the carboplatin formulation for intratumoral administration, and a second study to evaluate the efficacy and toxicosis of intratumoral administration of carboplatin in purified sesame oil. ANIMALS: 23 cats with squamous cell carcinomas of the nasal plane. PROCEDURE: Eight cats with advanced-stage tumors were submitted to intratumoral administration of 100 mg of carboplatin/m2 of body surface area, with or without purified sesame oil, using a two-period, cross-over design. Fifteen additional cats were treated by intratumoral administration of carboplatin in purified sesame oil. Four weekly intratumoral chemotherapy injections of carboplatin in purified sesame oil at a dosage of 1.5 mg/cm3 of tissue were given. RESULTS: Purified sesame oil in the formulation significantly reduced systemic exposure to carboplatin and drug leakage from the sites of injection. Cumulative effects of repeated intratumoral administrations on plasma concentrations of carboplatin were not observed. Systemic toxicosis was not observed, and local toxicosis was minimal. Healing of ulcerated lesions was not compromised. Rates of complete clinical tumor clearance and complete response were 67 and 73.3%, respectively. Product-limit estimates of mean progression-free survival times was 16 +/- 3.3 months. The 1-year progression-free survival rate was 55.1 +/- 13%. Local recurrence was observed in 7 cats; 4 had marginal tumor recurrence, and 3 had in-field and marginal tumor recurrence. CONCLUSIONS: Intratumoral carboplatin chemotherapy is safe and effective for cats with squamous cell carcinoma of the nasal plane. Future studies to improve treatment efficacy could include evaluation of increased dose-intensity as well as combination of this modality with radiotherapy. CLINICAL RELEVANCE: Intratumoral administration of carboplatin in a water-sesame-oil emulsion was found to be a practical and effective new treatment for facial squamous cell carcinomas in cats.  相似文献   

10.
11.
A patatin-like protein is present in the storage tissue of cucumber seedlings during the stage of fat mobilization. The cucumber protein is a homologue of a glycoprotein which in potatoes accounts for most of the total protein content of tubers. Following preparation of a cucumber cDNA library representing the developmental stage of cotyledons of 1 day old germinating seeds we isolated and characterized a clone encoding a patatin-like protein. Antibodies raised against the protein expressed in bacteria were used for immunodetection in subcellular fractions of cucumber seedlings. It was shown that the patatin-like protein was virtually exclusively confined to lipid bodies. The protein expressed in bacteria was characterized in vitro by its esterase activity acting on monoacylglycerols and phospholipids. Detailed analysis using various forms of phosphatidyl choline as substrates demonstrated that the patatin-like protein is a phospholipase A2 acting on palmitoyl, linoleoyl and hydroperoxidized linoleoyl groups equally well. Studying the temporal and tissue-specific expression of patatin-like protein mRNA we showed its appearance exclusively during fat catabolism. As maximal amounts of the protein were found at an early stage of mobilization and confined to lipid bodies, we propose that the patatin-like hydrolase is involved in lipid body mobilization.  相似文献   

12.
PURPOSE: This retrospective study was undertaken to assess the occurrence of postoperative anterior chamber emulsified silicone oil after intravitreal instillation and to examine the relation between such emulsification and new postoperative glaucoma. METHODS: Forty-eight consecutive eyes received intravitreal silicone oil, were followed for at least 1 year, and were evaluated postoperatively by gonioscopy on at least one occasion. Eight eyes received 1000 cs oil, and 40 eyes received 5000 cs oil from which low molecular weight contaminants were removed. All aphakic and pseudophakic eyes received an inferior iridectomy. Oil was removed in 19% of eyes during follow-up. RESULTS: Fifty-six percent of eyes manifested anterior chamber emulsified oil postoperatively. The oil was typically identified only on gonioscopy. This complication developed in 50% of eyes receiving 1000 cs oil and 58% of eyes receiving highly homogeneous 5000 cs oil. Of the 48 eyes, new postoperative glaucoma best explained by interval angle oil emulsification developed in 5 (10%). CONCLUSION: Anterior chamber oil emulsification occurred frequently, despite inferior peripheral iridectomy in aphakic or pseudophakic eyes and the use of highly purified, higher viscosity oil in 83% of eyes. In this series, new glaucoma in the setting of angle oil emulsification only developed in 10% of eyes. The glaucoma was managed medically in four of five patients.  相似文献   

13.
Oleosins are amphipathic proteins associated with oil bodies in seeds. We purified the major 16,500 peanut oleosin by preparative SDS-PAGE. Autoradiography after SDS-PAGE separation of the iodinated oleosin revealed covalently bound oligomers with Mr of 21,000, 33,000, 44,000 and 51,000. The strong capacity of these oligomers to form aggregates and to be incorporated into large-sized detergent micelles was demonstrated by gel permeation and isoelectric focusing. A 50% ethanol concentration was necessary to elute the 16,500 oleosin from octyl groups in hydrophobic interaction chromatography showing its natural tendency to interact with lipid acyl chains. This oligomerization behavior in aqueous solution is an indirect reflection of the interactions that occur in the oil body.  相似文献   

14.
Transcorneal permeation of ketorolac from oil based ocular drops and ophthalmic ointments was studied in vitro, using goat cornea. Cumulative (%) permeation of ketorolac through cornea, was found to be maximum with 0.2% (w/v) ketorolac drops in sesame oil followed by formulations in corn oil and soyabean oil. Ketorolac 1% (w/v) drops in castor oil increased the quantity permeated but cumulative (%) permeation was less. Permeation profiles of ketorolac were in consistence with the partition characteristic of drug between oil and aqueous phase. Formulations favouring corneal permeation of ketorolac increased corneal hydration. Addition of benzyl alcohol, a preservative, to oil drops reduced permeation of ketorolac and corneal hydration indicating possible protective effect of benzyl alcohol against corneal damage. Permeation studies on ointment formulations containing either ketorolac acid or ketorolac tromethamine salt indicated better permeation for formulation containing ketorolac tromethamine aqueous solution. Thus for better transcorneal permeation, ketorolac 0.2% (w/v) drops, formulated in sesame oil, containing 0.5% v/v benzyl alcohol and ophthalmic ointment containing 0.5% (w/w) ketorolac tromethamine in dissolved state appear suitable.  相似文献   

15.
This study tests the hypothesis that increased levels of plasma lipids can accelerate accumulation of myocardial triacylglycerols in post-ischemic but viable myocardium. Two groups of dogs underwent 90 min of left anterior descending coronary artery (LAD) occlusion followed by 240 min of reperfusion. The first group of saline-treated dogs (n = 7) had physiological levels of plasma lipids during reperfusion: a second group treated with Liposyn and heparin (n = 5) experienced increased plasma lipids during reperfusion. The transmural content of triacylglycerols was determined during ischemia and reperfusion using 1H NMR one-dimensional chemical shift imaging (1D CSI), and at the end of reperfusion using Oil Red-O staining and chemical assay. TTC staining was used to identify the extent of irreversibly injured myocardium. Subepicardial and plasma triacylglycerol content, measured both by 1D CSI and chemically, did not change during reperfusion in saline-treated dogs. Infusing dogs with Liposyn and heparin for 90 min during reperfusion transiently elevated their plasma triacylglycerols, which returned to normal levels following Liposyn wash-out. During Liposyn wash-out, myocardial triacylglycerols measured by 1D CSI preferentially increased in the subepicardium of area-at-risk myocardium (P < 0.05). Triacylglycerol content, measured chemically, also increased in area-at-risk compared to non-ischemic subepicardium (P < 0.001). Significant endocardial damage occurred in both groups, but elevated levels of plasma lipids did not increase the size of the area-at-risk. Therefore, elevated plasma lipids caused a preferential accumulation of triacylglycerols in area-at-risk myocardium during reperfusion without exacerbating irreversible ischemic injury. These results are consistent with either inhibited fatty acid oxidation or mis-matched fatty acid extraction and oxidation in area-at-risk myocardium.  相似文献   

16.
Mammographic lesions that are pathognomonic for oil cysts require no further evaluation. Oil cysts, however, may first be discovered by ultrasonography. Between 1988 and 1995, we performed sonography of 26 oil cysts in 15 patients. Sonography was used to evaluate a palpable finding when an oil cyst was not initially perceived on the mammogram (47%) or as an initial evaluation of a palpable lump (33%); in addition, oil cysts were identified incidentally in 20% of cases. Retrospective review showed that the sonographic appearance of oil cysts is highly variable; only 8% mimic simple apocrine cysts. Twelve percent mimic an intracystic mass. Most have smooth walls (88%), are hypoechoic (65%), and have neither enhancement or shadowing (50%). The sonographic appearance of oil cysts can be suggestive of a pathologic lesion such as an intracystic carcinoma. Unnecessary biopsy can be avoided using directed mammography.  相似文献   

17.
稀土在杜仲上的应用研究   总被引:5,自引:0,他引:5  
选用易于观察研究的杜仲幼苗、幼林、种子、扦插用的枝条作为试验材料,研究了稀土在杜仲上的应用效果和施用技术,并研制了一种高效价廉的林用促长剂  相似文献   

18.
Allergy to kiwi, poppy seeds, and/or sesame seeds often occurs in patients with a simultaneous sensitization to nuts and flour. Previously cross reactions have been verified by RAST inhibition. In this study the nature of this cross-reactivity is further characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by immunoblotting to nitrocellulose. The degree of cross-reactivity among kiwi, sesame seeds, poppy seeds, hazelnuts, and rye grain was found to be very high in the patients studied. The existence of both cross-reacting and unique components was observed; however, the cross-reacting and unique components could be different for different patients.  相似文献   

19.
Beta-glucosidase and beta-galactosidase activity profile tested in different seeds during 24 h germination revealed reasonably high levels of activity in Vigna radiata, Cicer arietinum, and Trigonella foenum-graecum. In all seeds tested, beta-galactosidase activity was, in general, higher than that of beta-glucosidase. T. foenum-graecum seedlings exhibited maximal total and specific activities for both the enzymes during 72 h germination. Se supplementation as Na2SeO3 up to 0.75 ppm was found to be beneficial to growth and revealed selective enhancement of beta-galactosidase activity by 40% at 0.5 ppm Se. The activities of both the enzymes drastically decreased at 1.0 ppm level of Se supplementation. On the contrary, addition of Na2SeO3 in vitro up to 1 ppm to the enzyme extracts did not influence these activities. Hydrolytic rates of beta-glucosidase in both control and Se-supplemented groups were enhanced by 20% with 0.05 M glycerol in the medium and 30% at 0.1 M glycerol. The rates were marginally higher in Se-supplemented seedlings than the controls, irrespective of added glycerol in the medium. In contrast, hydrolysis by beta-galactosidase showed a trend of decrease in Se-supplemented seedlings compared to the control, when glycerol was present in the medium. Addition of Se in vitro in the assay medium showed no difference in the hydrolytic rate by beta-galactosidase when compared to control, while the activity of beta-glucosidase declined by 50%. Se-grown seedlings showed an enhancement of transglucosidation rate by 40% in the presence of 0.1 M glycerol. The study reveals a differential response to Se among the beta-galactosidase and beta-glucosidase of T. foenum-graecum with increase in the levels of beta-galactosidase activity.  相似文献   

20.
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