Publications by authors named "N Mertes"

The genomes of anaerobic ammonium-oxidizing (anammox) bacteria contain a gene cluster comprising genes of unusual fatty acid biosynthesis enzymes that were suggested to be involved in the synthesis of the unique "ladderane" lipids produced by these organisms. This cluster encodes an acyl carrier protein (denoted as "amxACP") and a variant of FabZ, an ACP-3-hydroxyacyl dehydratase. In this study, we characterize this enzyme, which we call anammox-specific FabZ ("amxFabZ"), to investigate the unresolved biosynthetic pathway of ladderane lipids.

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We introduce a family of bright, rhodamine-based calcium indicators with tuneable affinities and colors. The indicators can be specifically localized to different cellular compartments and are compatible with both fluorescence and bioluminescence readouts through conjugation to HaloTag fusion proteins. Importantly, their increase in fluorescence upon localization enables no-wash live-cell imaging, which greatly facilitates their use in biological assays.

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The self-labeling protein tags (SLPs) HaloTag7, SNAP-tag, and CLIP-tag allow the covalent labeling of fusion proteins with synthetic molecules for applications in bioimaging and biotechnology. To guide the selection of an SLP-substrate pair and provide guidelines for the design of substrates, we report a systematic and comparative study of the labeling kinetics and substrate specificities of HaloTag7, SNAP-tag, and CLIP-tag. HaloTag7 reaches almost diffusion-limited labeling rate constants with certain rhodamine substrates, which are more than 2 orders of magnitude higher than those of SNAP-tag for the corresponding substrates.

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Unlabelled: Single crystal structural analysis of [Fe (tame) ]Cl ⋅MeOH (tame=1,1,1-tris(aminomethyl)ethane) as a function of temperature reveals a smooth crossover between a high temperature high-spin octahedral d state and a low temperature low-spin ground state without change of the symmetry of the crystal structure. The temperature at which the high and low spin states are present in equal proportions is T =140 K. Single crystal, variable-temperature optical spectroscopy of [Fe (tame) ]Cl ⋅MeOH is consistent with this change in electronic ground state.

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Background/aims: A new lipid emulsion based on soybean oil, medium chain triglycerides, olive oil and fish oil (SMOFlipid) was tested for safety, tolerance, metabolic and clinical efficacy in surgical patients.

Methods: In a prospective, double-blind European multicenter study, postoperative patients (elective abdominal or thoracic surgery) were randomized to receive isonitrogenous, isoenergetic (30-35 kcal/kg) total parenteral nutrition over 5 postoperative days including either SMOFlipid 20% or standard soybean oil emulsion (Lipovenoes 20%) as lipid source (1.5 g kg(-1) day(-1)).

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