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11.
In the wild, primate foraging behaviors are related to the diversity and nutritional properties of food, which are affected by seasonal variation. The goal of environmental enrichment is to stimulate captive animals to exhibit similar foraging behavior of their wild counterparts, e.g. To extend foraging time. We conducted a 12-month study on the foraging behavior of Japanese macaques in a semi-naturally forested enclosure to understand how they use both provisioned foods and naturally available plant foods and what are the nutritional criteria of their consumption of natural plants. We recorded time spent feeding on provisioned and natural plant foods and collected the plant parts ingested of their major plant food species monthly, when available.We conducted nutritional analysis (crude protein, crude lipid, neutral detergent fiber-'NDF', ash) and calculated total non-slructural carbohydrate - 'TNC' and total energy of those food items. Monkeys spent 47% of their feeding time foraging on natural plant species. The consumption of plant parts varied significantly across seasons. We found that leaf items were consumed in months when crude protein, crude protein-to-NDF ratio, TNC and total energy were significantly higher and NDF was significantly lower, fruit/nut items in months when crude protein and TNC were significantly higher and crude lipid content was significantly lower, and bark items in months when TNC and total energy were higher and crude lipid content was lower. This preliminary investigation showed that the forested enclosure allowed troop members to more fully express their species typical flexible behavior by challenging them to adjust their foraging behavior to seasonal changes of plant item diversity and nutritional content, also providing the possibility for individuals to nutritionally enhance their diet. 相似文献
12.
We report a method to enrich cysteinyl adducts of human serum albumin (HSA), representing biomarkers of exposure to systemic electrophiles. Because the major site of HSA adduction is the single free sulfhydryl group at Cys34, we used thiol-affinity resins to remove mercaptalbumin (i.e., unadducted HSA) from the cysteinyl adducts. Electrospray ionization mass spectrometry was used to detect mercaptalbumin and HSA-Cys34 modifications before and after enrichment of HSA. Differences in adduct content were detected across samples of freshly isolated, archived, and commercial HSA. Cysteinylated and glycosylated adducts were present in all samples, with abundances decreasing in the following order: commercial HSA > archived HSA > fresh HSA. After enrichment of HSA, mercaptalbumin was no longer observed in mass spectra. The ratios of HSA adducts post-/preenrichment, quantified via the Bradford assay and gel electrophoresis, were 0.029 mg adducts/mg HSA in fresh HSA and 0.323 mg adducts/mg HSA in archived HSA. The apparent elevation of adduct levels in archived samples could be due to differences in specimen preparation and storage rather than to differences in circulating HSA adducts. We conclude that thiol-affinity resins can efficiently remove mercaptalbumin from HSA samples prior to characterization and quantitation of protein adducts of reactive systemic electrophiles. 相似文献
13.
Pablo Moreno Stephan Beisken Bhavana Harsha Venkatesh Muthukrishnan Ilinca Tudose Adriano Dekker Stefanie Dornfeldt Franziska Taruttis Ivo Grosse Janna Hastings Steffen Neumann Christoph Steinbeck 《BMC bioinformatics》2015,16(1)
Background
Ontology-based enrichment analysis aids in the interpretation and understanding of large-scale biological data. Ontologies are hierarchies of biologically relevant groupings. Using ontology annotations, which link ontology classes to biological entities, enrichment analysis methods assess whether there is a significant over or under representation of entities for ontology classes. While many tools exist that run enrichment analysis for protein sets annotated with the Gene Ontology, there are only a few that can be used for small molecules enrichment analysis.Results
We describe BiNChE, an enrichment analysis tool for small molecules based on the ChEBI Ontology. BiNChE displays an interactive graph that can be exported as a high-resolution image or in network formats. The tool provides plain, weighted and fragment analysis based on either the ChEBI Role Ontology or the ChEBI Structural Ontology.Conclusions
BiNChE aids in the exploration of large sets of small molecules produced within Metabolomics or other Systems Biology research contexts. The open-source tool provides easy and highly interactive web access to enrichment analysis with the ChEBI ontology tool and is additionally available as a standalone library.Electronic supplementary material
The online version of this article (doi:10.1186/s12859-015-0486-3) contains supplementary material, which is available to authorized users. 相似文献14.
Resolution and characterisation of multiple isoforms of bovine kappa-casein by 2-DE following a reversible cysteine-tagging enrichment strategy 总被引:1,自引:0,他引:1
Visualisation of multiple isoforms of kappa-casein on 2-D gels is restricted by the abundant alpha- and beta-caseins that not only limit gel loading but also migrate to similar regions as the more acidic kappa-casein isoforms. To overcome this problem, we took advantage of the absence of cysteine residues in alpha(S1)- and beta-casein by devising an affinity enrichment procedure based on reversible biotinylation of cysteine residues. Affinity capture of cysteine-containing proteins on avidin allowed the removal of the vast majority of alpha(S1)- and beta-casein, and on subsequent 2-D gel analysis 16 gel spots were identified as kappa-casein by PMF. Further analysis of the C-terminal tryptic peptide along with structural predictions based on mobility on the 2-D gel allowed us to assign identities to each spot in terms of genetic variant (A or B), phosphorylation status (1, 2 or 3) and glycosylation status (from 0 to 6). Eight isoforms of the A and B variants with the same PTMs were observed. When the casein fraction of milk from a single cow, homozygous for the B variant of kappa-casein, was used as the starting material, 17 isoforms from 13 gel spots were characterised. Analysis of isoforms of low abundance proved challenging due to the low amount of material that could be extracted from the gels as well as the lability of the PTMs during MS analysis. However, we were able to identify a previously unrecognised site, T(166), that could be phosphorylated or glycosylated. Despite many decades of analysis of milk proteins, the reasons for this high level of heterogeneity are still not clear. 相似文献
15.
16.
Lars Ola Nilsson Håkan Wallander Erland Bååth Ursula Falkengren-Grerup 《Biogeochemistry》2006,80(1):43-55
Anthropogenic N deposition may change soil conditions in forest ecosystems as demonstrated in many studies of coniferous forests,
whereas results from deciduous forests are relatively scarce. Therefore the influence of N deposition on several variables
was studied in situ in 45 oak-dominated deciduous forests along a N deposition gradient in southern Sweden, where the deposition ranged from
10 to 20 kg N ha−1 year−1. Locally estimated NO
−
3
deposition, as measured with ion-exchange resins (IER) on the soil surface, and grass N concentration (%) were positively
correlated with earlier modelled regional N deposition. Furthermore, the δ15N values of grass and uppermost soil layers were negatively correlated with earlier modelled N deposition. The data on soil
NO
−
3
, measured with IER in the soil, and grass N concentration suggest increased soil N availability as a result of N deposition.
The δ15N values of grass and uppermost soil layers indicate increased nitrification rates in high N deposition sites, but no large
downward movements of NO
−
3
in these soils. Only a few sites had NO
−
3
concentrations exceeding 1 mg N l−1 in soil solution at 50 cm depth, which showed that N deposition to these acid oak-dominated forests has not yet resulted
in extensive leaching of N. The δ15N enrichment factor was the variable best correlated with NO
−
3
concentrations at 50 cm and is thus a variable that potentially may be used to predict leaching of NO
−
3
from forest soils. 相似文献
17.
Here we describe a new method for preparing a protein-imprinted polymer with a cloned bacterial protein template, which recognizes/adsorbs authentic target protein present at a relatively low level in cell extract. In this work, cloned pig cyclophilin 18 (pCyP18) was used as a template. The template protein was selectively assembled with memory molecules from their library, which consists of numerous limited length polymer chains with randomly distributed recognition sites and immobilizing sites. These assemblies of protein and memory molecules were adsorbed by porous polymeric beads and immobilized by cross-linking polymerization. After removing the template, binding sites that were complementary to the target protein in size, shape and the position of recognition groups were exposed, and their confirmation was preserved by the cross-linked structure. The synthesized imprinted polymer was used to adsorb authentic pCyP18 from cell extract, and its proportional content was enriched 300 times. 相似文献
18.
Zhang K 《Analytical biochemistry》2006,357(2):225-231
Through years of practice, mass spectrometry has proven to be one of the most reliable and sensitive methods for the localization of protein phosphorylation sites. Among numerous innovative methods, affinity enrichment such as immobilized metal-ion affinity chromatography followed by liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis appears to be the most widely chosen procedure. Here, I report a method that was originally designed for purification of large amounts of nucleotides using anion-exchanging resin but has shown the promise of enriching phosphorylated peptides. Mixtures composed of uridine monophosphate, uridine diphosphate, uridine triphosphate, and their nonphosphate compound-uridine were bottom-line separated on an anion-exchanging solid-phase extraction (SPE) column by four steps of elution with a gradient of salt concentration and pH values. The miniature form of this SPE column showed significant separation (or enrichment) of the tryptic phospho-peptides from non-phospho-peptides of the standard protein beta-casein with two steps of elution (100mM NaCl and 5% NH(4)OH). Furthermore, after utilization of this anion-exchanging-column enrichment followed by LC/MS/MS analysis on a quadrupole-tine of flight instrument, a new phosphorylation site (S191) in bovine chromogranin A was identified. 相似文献
19.
Darias MJ Boglino A Manchado M Ortiz-Delgado JB Estévez A Andree KB Gisbert E 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2012,161(2):130-139
The present study aimed to deepen the understanding of molecular mechanisms governing the absorption and metabolism of some nutrients, growth and development in larvae of Senegalese sole (Solea senegalensis) fed with Artemia enriched with Easy Selco© (ES, INVE) or Aquagrow Gold© (AGG, ABN), which mainly differed in their vitamin A (VA) content and fatty acid composition. The expression profile of genes involved in VA metabolism (crbp2, rbp, crabp1), lipid transport (i-fabp, l-fabp), nuclear receptors for VA and fatty acids (rarα1, rxrα, pparβ), growth (igf1, igf2 and their receptor igf1r) and development (bgp) was analyzed at 22, 30 and 38 days post hatching. The main results suggested that the amount of VA absorbed by larvae is controlled at the intestinal level by crbp2 in both groups, preventing excessive accumulation of this vitamin in the target tissues. The stable expression of i-fabp in the ES group with age could cause an excessive fat accumulation in the intestine inducing, in turn, the steatosis found in the liver and vascular system of these specimens. In liver, the regulation of rbp and fabp expression reflected the status of the physiological functions demanding VA and lipids. The findings revealed that dietary composition induced different strategies for VA and lipid absorption and metabolism affecting, in turn, larval development, growth and health. 相似文献
20.