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Human C-C motif ligand 16 (CCL16) is a chemokine that is distinguished by a large cleavable C-terminal extension of unknown significance. Conflicting data have been reported concerning its tissue distribution and modulation of expression, rendering the biological function of CCL16 enigmatic. Here, we report an integrated approach to the characterisation of this chemokine, including a re-assessment of its expression characteristics as well as a biophysical investigation with respect to its structure and dynamics. Our data indicate that CCL16 is chiefly synthesised by hepatocytes, without an appreciable response to mediators of inflammation, and circulates in the blood as a full-length protein. While the crystal structure of CCL16 confirms the presence of a canonical chemokine domain, molecular dynamics simulations support the view that the C-terminal extension impairs the accessibility of the glycosaminoglycan binding sites and may thus serve as an intrinsic modulator of biological activity. [ABSTRACT FROM AUTHOR]

In this study, we developed and validated a CE-TOF-MS method for the quantification of glyphosate (N-(phosphonomethyl)glycine) and its major degradation product aminomethylphosphonic acid (AMPA) in different samples including beer, media from toxicological analysis with Daphnia magna, and sorption experiments. Using a background electrolyte (BGE) of very low pH, where glyphosate is still negatively charged but many matrix components become neutral or protonated, a very high separation selectivity was reached. The presence of inorganic salts in the sample was advantageous with regard to preconcentration via transient isotachophoresis. The advantages of our new method are the following: no derivatization is needed, high separation selectivity and thus matrix tolerance, speed of analysis, limits of detection suitable for many applications in food and environmental science, negligible disturbance by metal chelation. LODs for glyphosate were < 5 μg/L for both aqueous and beer samples, the linear range in aqueous samples was 5–3000 μg/L, for beer samples 10–3000 μg/L. For AMPA, LODs were 3.3 and 30.6 μg/L, and the linear range 10–3000 μg/L and 50–3000 μg/L, for aqueous and beer samples, respectively. Recoveries in beer samples for glyphosate were 94.3–110.7% and for AMPA 80.2–100.4%. We analyzed 12 German and 2 Danish beer samples. Quantification of glyphosate and AMPA was possible using isotopically labeled standards without enrichment, purification, or dilution, only degassing and filtration were required for sample preparation. Finally, we demonstrate the applicability of the method for other strong acids, relevant in food and environmental sciences such as N-acetyl glyphosate, N-acetyl AMPA (present in some glyphosate resistant crop), trifluoroacetic acid, 2-methyl-4-chlorophenoxyacetic acid, glufosinate and its degradation product 3-(methylphosphinico)propionic acid, oxamic acid, and others. [ABSTRACT FROM AUTHOR]

Polyamines are small poly-cations essential for all cellular life. The main polyamines present in metazoans are putrescine, spermidine and spermine. Their exact functions are still largely unclear; however, they are involved in a wide variety of processes affecting cell growth, proliferation, apoptosis and aging. Here we identify idefix, a mutation in the zebrafish gene encoding the enzyme spermidine synthase, leading to a severe reduction in spermidine levels as shown by capillary electrophoresis-mass spectrometry. We show that spermidine, but not spermine, is essential for early development, organogenesis and colour pattern formation. Whereas in other vertebrates spermidine deficiency leads to very early embryonic lethality, maternally provided spermidine synthase in zebrafish is sufficient to rescue the early developmental defects. This allows us to uncouple them from events occurring later during colour patterning. Factors involved in the cellular interactions essential for colour patterning, likely targets for spermidine, are the gap junction components Cx41.8, Cx39.4, and Kir7.1, an inwardly rectifying potassium channel, all known to be regulated by polyamines. Thus, zebrafish provide a vertebrate model to study the in vivo effects of polyamines., (© 2016. Published by The Company of Biologists Ltd.)

Coatings are necessary to prevent protein and peptide adsorption to the capillary surface and obtain high intermediate precision. In this protocol, we first present our basic strategy to address peptide separation using three different coatings: one neutral and two cationic coatings, the latter largely differing in their induced electroosmotic mobility. In detail, we will describe how we apply the statically adsorbed coatings to obtain very high plate numbers and high repeatability.With some model examples, we clearly describe the scope of the method for the analysis of peptide samples: tryptic digests are addressed as well as small glycoproteins and glycopeptides largely differing in their effective electrophoretic mobility. We also show that the method is suitable for a fast screening of peptide samples despite a high matrix load comprising of up to 500 mmol/L sodium chloride. We demonstrate that this basic CE-MS method is rather independent of the polarity of the analytes with a very fast near-baseline separation of very hydrophobic Aβ peptides related to the onset of Alzheimer's disease. These examples will give an impression, which coating is most suitable for a specific analytical application.Special attention is paid to difficult aspects of the coating procedure and the CE-MS method, e.g., the potential of cross-contamination when changing the coatings.