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The high molecular weight glutenin subunits (HMW-GS) play a key role in end-use quality of wheat. Their particular primary structure is mostly derived from DNA sequencing, which gives no information on potential post-translational modifications. This paper reveals the primary structure of HMW-GS 1Dx2 by proteomic analysis. For this purpose, HMW-GS were first isolated from wheat flour (cv. Contra). The relative molecular mass (Mr) of subunit 1Dx2 present in the HMW-GS mixture was then very accurately determined with high-performance liquid chromatography–electrospray ionization-mass spectrometry using a quadrupole-time-of-flight mass analyzer (HPLC–ESI-QTOF-MS). The obtained Mr value (87,105) differed from the value derived from its protein sequence in the NCBI database (87,007). The subunit was further purified by preparative reversed-phase HPLC and partially hydrolyzed with chymotrypsin. The resulting 1Dx2 peptides were then analyzed by HPLC–ESI-MS/MS and the MS data were compared to amino acid sequences in protein databases. The discrepancy between the calculated and the measured Mr of 1Dx2 was explained by a missing proline in the 1Dx2 amino acid sequence from the database and not by any post-translational glycosylation. 相似文献
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The optimal lignin quantification method to breed for an improved cell wall digestibility in perennial ryegrass 
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下载免费PDF全文 F. van Parijs C. Van Waes B. Vandecasteele G. Haesaert I. Roldán‐Ruiz H. Muylle 《Grass and Forage Science》2018,73(1):101-111
Perennial ryegrass (Lolium perenne) is an important source of protein and energy for dairy cattle. To improve the protein/energy ratio of this forage, focus is now on improving its cell wall digestibility. The in vitro assessment of the digestible fraction of the neutral detergent fibre (NDFD) is a superior method for determining the cell wall digestibility, but requires the use of ruminal fluid, which has a highly variable composition and is often not readily available. As lignin is considered the main cell wall component that impedes NDFD, we investigated whether this “subtrait” could serve as alternative breeding selection criterion to improve NDFD. Therefore, we assessed the accuracy of two lignin quantification methods: van Soest (ADL) and Klason lignin (KL). We also considered KL estimates corrected for the solubilized lignin (total lignin or TL) and non‐solubilized protein (TL'). Although the latter is considered the truest possible lignin content, it was not always the most correlated to NDFD, due to the limited accuracy of protein quantification on lignin residue. TL is most correlated to NDFD and we therefore recommend it for use in conventional breeding if NDFD determination is not a possibility. However, NDFD is still a superior selection criterion, as it combines the effect of several subtraits and not just lignin. For marker–trait association studies, a more accurate estimate of lignin content is more important than a high correlation with NDFD, but also here, TL performs best. 相似文献
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Ine Dorresteijn Jannik Schultner Neil French Collier Kristoffer Hylander Feyera Senbeta Joern Fischer 《Landscape Ecology》2017,32(11):2151-2165
Context
Cultural landscapes provide essential ecosystem services to local communities, especially in poor rural settings. However, potentially negative impacts of ecosystems—or disservices—remain inadequately understood. Similarly, how benefit–cost outcomes differ within communities is unclear, but potentially important for cultural landscape management.Objectives
Here we investigated whether distinct forest ecosystem service–disservice outcomes emerge within local communities. We aimed to characterize groups of community members according to service–disservice outcomes, and assessed their attitudes towards the forest.Methods
We interviewed 150 rural households in southwestern Ethiopia about locally relevant ecosystem services (provisioning services) and disservices (wildlife impacts). Households were grouped based on their ecosystem service–disservice profiles through hierarchical clustering. We used linear models to assess differences between groups in geographic and socioeconomic characteristics, as well as attitudes toward the forest.Results
We identified three groups with distinct ecosystem service–disservice profiles. Half of the households fell into a “lose–lose” profile (low benefits, high costs), while fewer had “lose–escape” (low benefits, low costs) and “win–lose” (high benefits, high costs) profiles. Location relative to forest and altitude explained differences between the “lose–escape” profile and other households. Socioeconomic factors were also important. “Win–lose” households appeared to be wealthier and had better forest use rights compared to “lose–lose” households. Attitudes towards the forest did not differ between profiles.Conclusions
Our study demonstrates the importance of disaggregating both ecosystem services and disservices, instead of assuming that communities receive benefits and costs homogenously. To manage cultural landscapes sustainably, such heterogeneity must be acknowledged and better understood.14.
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Ine Dorresteijn Jan Hanspach Attila Kecskés Hana Latková Zsófia Mezey Szilárd Sugár Henrik von Wehrden Joern Fischer 《Landscape Ecology》2014,29(7):1145-1155
Facilitating human-carnivore coexistence is a major conservation concern in human-dominated landscapes worldwide. Useful insights could be gained by studying and understanding the dynamics of human-carnivore coexistence in landscapes in which carnivores and humans have coexisted for a long time. We used a two-pronged approach combining ecological and social data to study coexistence of the brown bear (Ursus arctos) and humans in Transylvania, Romania. First, we surveyed 554 km of walking transects to estimate activity via a bear sign index, namely the proportion of anthills disturbed by bears, and used spatially explicit predictive models to test which biophysical and anthropogenic variables influenced bear activity. Second, we interviewed 86 shepherds and 359 villagers and community representatives to assess conflicts with bears and attitudes of shepherds towards bears. Our interdisciplinary study showed that bears and humans coexisted relatively peacefully despite occasional conflicts. Coexistence appeared to be facilitated by: (1) the availability of large forest blocks that are connected to the source population of bears in the Carpathian Mountains; (2) the use of traditional livestock management to minimize damage from bears; and (3) some tolerance among shepherds to occasional conflict with bears. In contrast, bear activity was unrelated to human settlements, and compensation for livestock losses did not influence people’s attitudes toward bears. Our study shows that coexistence of humans and carnivores is possible, even without direct economic incentives. A key challenge for settings with a discontinuous history of human-carnivore coexistence is to reinstate both practices and attitudes that facilitate coexistence. 相似文献
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Lagrain B Rombouts I Brijs K Delcour JA 《Journal of agricultural and food chemistry》2011,59(5):2034-2039
The kinetics of heat-induced polymerization of gliadin, that is, a mixture of monomeric wheat storage proteins, was studied using a model system. Samples were heated at pH 6.0 and 8.0 at 110, 120, and 130 °C for up to 240 min, and their extractabilities were compared under nonreducing and reducing (with 1% dithiothreitol) conditions. Extraction media were sodium dodecyl sulfate (SDS) containing buffer (pH 6.8, SDS buffer) and/or 70% ethanol. Gliadin cross-linking mainly resulted from intermolecular disulfide (SS) bond formation. At higher temperatures and, preferably, alkaline pH, intramolecular SS bonds in gliadin underwent β-elimination reactions, leading to the formation of dehydroalanine (DHA) and free sulfhydryl (SH) groups. The latter interchanged rapidly with SS bonds, leading to intermolecular SS bonds and gliadin extractability loss. When free SH groups had been formed, gliadin extractability in SDS buffer decreased following first-order reaction kinetics, the reaction rate constant of which increased with temperature and pH. Furthermore, the extractabilities of α- and γ-gliadin in 70% ethanol decreased according to first-order reaction kinetics. ω-Gliadin extractability was much less affected. Under the experimental conditions, gliadin polymerization through SH-SS interchange occurred much more rapidly than β-elimination of cystine. 相似文献
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The Pulmonary Veins of the Pig as an Anatomical Model for the Development of a New Treatment for Atrial Fibrillation 下载免费PDF全文
下载免费PDF全文 T. Vandecasteele K. Vandevelde M. Doom E. Van Mulken P. Simoens P. Cornillie 《Anatomia, histologia, embryologia》2015,44(1):1-12
The layout of the porcine atriopulmonary junction and immediately adjacent structures was investigated by gross anatomical and vascular corrosion casting studies to meet the need for more in‐depth anatomical insights when using the pig as an animal model in the development of innovative approaches for surgical cardiac ablation in man. The veins from the right cranial and middle lung lobes drain through a common ostium in the left atrium, whereas a second ostium receives the blood returning from all other lung lobes, although limited variation to this pattern was observed. Surrounding anatomical structures that are most vulnerable to ablation damage as reported in man are located at a safer distance from the pulmonary veins in pigs, yet a certain locations, comparable risks are to be considered. Additionally, it was histologically confirmed that myocardial sleeves extend to over a centimetre in the wall of the pulmonary veins. 相似文献
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Patrick D. Culbert Ine Dorresteijn Jacqueline Loos Murray K. Clayton Joern Fischer Tobias Kuemmerle 《Landscape Ecology》2017,32(2):429-444