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1.
In this study some aspects of organic and amino acid metabolism in cherry endocarp and seed were investigated during their development. The abundance and location of a number of enzymes involved in these processes were investigated. These enzymes were aspartate aminotransferase (AspAT; EC:2.6.1.1), glutamine synthetase (GS; EC:6.3.1.2), phosphoenolpyruvate carboxylase (PEPC; EC:4.1.1.31), phosphoenolpyruvate carboxykinase (PEPCK; EC:4.1.1.49), and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC:4.1.1.39). There was a transient and massive accumulation of vegetative storage proteins in the endocarp. These proteins were remobilised as the endocarp lignified and at the same time that proteins were accumulated in the seed. This raised the possibility that a proportion of imported amino acids were temporarily stored in the endocarp as protein, and that these were later utilised by the seed when it started to accumulate storage proteins. Rubisco was present in the embryo and integuments of the seed although no chlorophyll was present. This is the first time that Rubisco has been detected in non-green seeds. The maximum abundance of Rubisco in the seed coincided with the deposition of seed storage proteins. A possible function for Rubisco in cherry seed is discussed. PEPCK was located in the integuments and appeared when seed storage proteins were being accumulated. In the integuments and embryo AspAT, GS, PEPC and Rubisco also appeared, or greatly increased in abundance, when seed storage proteins were being deposited.  相似文献   
2.
Two cell lines, designated MARC.OVSM, and MARC.OKF, were initiated from the aorta and kidney, respectively, obtained from the Texel ram used to make the CHORI-243 Ovine BAC library. These cell lines have been submitted to the NIA Aging Cell Repository at the Coriell Cell Respositories, Camden, NJ, USA, and will be made publicly available.  相似文献   
3.
Artemia urmiana (a species previously considered endemic of Lake Urmia, NW Iran) has been found in Lake Koyashskoe, a hypersaline lake on the Black Sea coast of the Crimean peninsula (Ukraine). Therefore, this is the first record of A. urmiana in Europe which updates its distribution. The species identification was based on an integrated and interdisciplinary approach using discriminant analysis of the morphometric characters, scanning electron microscopy, and molecular profile analysis. The data derived from the above mentioned approaches converge to significant similarity of the population under investigation with A. urmiana. The updated geographic distribution of the species, deriving from the present report, asks for additional contribution of other disciplines (e.g., avian dispersal of cysts, history of salt trade) to be finally clarified. At present we suggest that the punctuated geographic distribution of A. urmiana is probably linked to its low dispersal capability, and we suppose that its presence in two distant sites could be explained by historical human salt trade between Lake Urmia and the ancient port of Kimmerik, whose remains have been found in the present Lake Koyashskoe. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
4.
Modifications to the composition of starch, the major component of wheat flour, can have a profound effect on the nutritional and technological characteristics of the flour's end products. The starch synthesized in the grain of conventional wheats (Triticum aestivum) is a 3:1 mixture of the two polysaccharides amylopectin and amylose. Altering the activity of certain key starch synthesis enzymes (GBSSI, SSIIa and SBEIIa) has succeeded in generating starches containing a different polysaccharide ratio. Here, mutagenesis, followed by a conventional marker‐assisted breeding exercise, has been used to generate three mutant lines that produce starch with an amylose contents of 0%, 46% and 79%. The direct and pleiotropic effects of the multiple mutation lines were identified at both the biochemical and molecular levels. Both the structure and composition of the starch were materially altered, changes which affected the functionality of the starch. An analysis of sugar and nonstarch polysaccharide content in the endosperm suggested an impact of the mutations on the carbon allocation process, suggesting the existence of cross‐talk between the starch and carbohydrate synthesis pathways.  相似文献   
5.
Malate is accumulated in grape pericarp until the start of ripening and then it is dissimilated. One aim of this study was to determine if the potential contribution of stored malate to the substrate requirements of metabolism in ripening grape pericarp is dependent on the cultivar. Two Vitis vinifera L. cultivars which accumulated different amounts of malate and had ripening periods of a different length were compared. The potential contribution of stored malate over the whole period of ripening was around 20 % in the cv. Sagrantino and 29 % in the cv. Pinot Noir. The contribution was higher in Pinot Noir because it contained more malate and had a shorter ripening period. A second aim of this study was to evaluate the contribution of gluconeogenesis to the amount of sugar accumulated in the pericarp. If all the dissimilated malate was utilized by gluconeogenesis, then the maximum contribution of stored malate to the total amount of sugar accumulated in the pericarp over the whole period of ripening was around 2.4 % in Sagrantino and 2.9 % in Pinot Noir. However, the actual contribution was only about 0.1–0.6 % in both cultivars because the majority of stored malate was not utilized by gluconeogenesis. However, it is likely that the actual contribution is much lower. This suggests that the function of gluconeogenesis is not to support accumulation of sugars in the fruits, but probably it plays other roles.  相似文献   
6.
7.
In this study the abundance and location of phosphoenolpyruvate carboxykinase (PEPCK) was determined in the flesh and skin of the sweet cherry (Prunus avium L.) cultivar Durone Nero II during development. PEPCK was not present in young fruit but appeared in both tissues as the fruit increased in size. In these there was no net dissimilation of malic acid, which accounts for the bulk of their organic acid contents when PEPCK was present. To assist in understanding the function of PEPCK, the abundance of a number of other enzymes was determined. These enzymes were aspartate aminotransferase (AspAT), glutamine synthetase (GS), phosphoenolpyruvate carboxylase (PEPC), pyruvate, orthophosphate dikinase (PPDK), and ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco). A potential role for PEPCK in the regulation of pH and the utilization of malate in gluconeogenesis in the flesh and skin of cherries is presented.  相似文献   
8.
Yersiniabactin (Ybt) is a metal‐binding natural product that has been re‐purposed for water treatment. The early focus of this study was the characterization of metal binding breadth attributed to Ybt. Using LC‐MS analysis of water samples exposed to aqueous and surface‐localized Ybt, quantitative assessment of binding was completed with metals that included Pd2+, Mg2+, and Zn2+. In total, Ybt showed affinity for 10 metals. Next, Ybt‐modified XAD‐16N resin (Ybt‐XAD) was utilized to quantify the affinity for metal removal, showing a rank order of Fe3+ > Ga3+ > Ni2+ > Cu2+ > Cr2+≈Zn2+ > Co2+ > Pd2+ > Mg2+ > Al3+, and in the applied treatment of wastewater from a local precious metal plating company, showing selective removal of nickel from the aqueous effluent. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1548–1554, 2017  相似文献   
9.
Yersiniabactin (Ybt) is a mixed nonribosomal peptide‐polyketide natural product that binds a wide range of metals with the potential to impact processes requiring metal retrieval and removal. In this work, we substantially improved upon the heterologous production of Ybt and an associated anthranilate analog through systematic screening and optimization of culture medium components. Specifically, a Plackett‐Burman design‐of‐experiments methodology was used to screen 22 components and to determine those contributing most to siderophore production. L‐cysteine, L‐serine, glucose, and casamino acids significantly contributed to the production of both compounds. Using this approach together with metabolic engineering of the base biosynthetic process, Ybt and the anthranilate analog titers were increased to 867 ± 121 mg/L and 16.6 ± 0.3 mg/L, respectively, an increase of ~38 and ~79‐fold relative to production in M9 medium. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1193–1200, 2017  相似文献   
10.
Considerable epidemiological evidence exists to link thyroid disease with differing patterns of dietary consumption, in particular, cruciferous vegetables. We have been studying the anti-thyroid cancer (TCa) activity of indole-3-carbinol (I3C) found in cruciferous vegetables and its acid catalyzed dimer, 3,3'-diindolylmethane (DIM). There are no studies as yet to elucidate the effect of these compounds on the altered proliferative patterns in goiter or thyroid neoplasia. In this study, we tested the anti-proliferative effects of I3C and DIM on four different thyroid cancer cell lines representative of papillary (B-CPAP and 8505-C) and follicular carcinoma of the thyroid (CGTH-W-1 and ML-1), and primary human goiter cells. Cell survival and IC50 values for I3C and DIM were calculated by the XTT assay and cell cycle distribution analysis was done by flow cytometry. DIM was found to be a better anti-proliferative agent than I3C in both papillary and follicular TCa resulting in a greater cytotoxic effect at a concentration over three fold lower than predicted by the molar ratio of DIM and I3C. The anti-proliferative activity of DIM in follicular TCa was mediated by a G1 arrest followed by induction of apoptosis. DIM also inhibited the growth of primary goiter cells by 70% compared to untreated controls. Contrary to traditional belief that cruciferous vegetables are "goitrogenic", DIM has anti-proliferative effects in glandular thyroid proliferative disease. Our preclinical studies provide a strong rationale for the clinical exploration of DIM as an adjuvant to surgery in thyroid proliferative disease.  相似文献   
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