Publications by authors named "Robert Kottler"

The gut microbiota evolves rapidly after birth, responding dynamically to environmental factors and playing a key role in short- and long-term health. Lifestyle and rurality have been shown to contribute to differences in the gut microbiome, including levels, between infants. We studied the composition, function and variability of the gut microbiomes of 6- to 11-month-old Kenyan infants ( = 105).

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Background: Whether prebiotic human milk oligosaccharides (HMO), such as 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT), enhance iron absorption in infants is unknown. Moreover, whether maternal HMO profile affects absorption of iron fortificants or the effects of prebiotic galacto-oligosaccharides (GOS) and/or HMO on iron absorption is uncertain.

Objectives: The aim of this study was to test whether consumption of 3.

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Relative abundances of bacterial species in the gut microbiome have been linked to many diseases. Species of gut bacteria are ecologically differentiated by their abilities to metabolize different glycans, making glycan delivery a powerful way to alter the microbiome to promote health. Here, we study the properties and therapeutic potential of chemically diverse synthetic glycans (SGs).

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Among the human milk oligosaccharides (HMOS), the galactosyllactoses (GLs) are only limitedly studied. This study aims to describe the presence and relative levels of HMOS, including GLs, in human milk (HM) according to maternal Secretor and Lewis () phenotype and lactation stage. Relative levels of 19 HMOS were measured in 715 HM samples collected in the first 4 months postpartum from 371 donors participating in the PreventCD study.

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A wide range of glycoproteins can be recombinantly expressed in aglycosylated forms in bacterial and cell-free production systems. To investigate the effect of glycosylation of these proteins on receptor binding, stability, efficacy as drugs, pharmacodynamics and pharmacokinetics, an efficient glycosylation platform is required. Here, we present a cell-free synthetic platform for the in vitro N-glycosylation of peptides mimicking the endoplasmic reticulum (ER) glycosylation machinery of eukaryotes.

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The unambiguous mass spectrometric identification and characterization of glycopeptides is crucial to elucidate the micro- and macroheterogeneity of glycoproteins. Here, combining lower and stepped collisional energy fragmentation for the in-depth and site-specific analysis of N- and O-glycopeptides is proposed. Using a set of four representative and biopharmaceutically relevant glycoproteins (IgG, fibrinogen, lactotransferrin, and ribonuclease B), the benefits and limitations of the developed workflow are highlighted and a state-of-the-art blueprint for conducting high-quality in-depth N- and O-glycoproteomic analyses is provided.

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Facilitated by substantial advances in analytical methods, plasma N-glycans have emerged as potential candidates for biomarkers. In the recent years, several investigations could link aberrant plasma N-glycosylation to numerous diseases. However, due to often limited specificity and sensitivity, only a very limited number of glycan biomarkers were approved by the authorities up to now.

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The ongoing threat of pathogens, increasing resistance against antibiotics, and the risk of fast spreading of infectious diseases in a global community resulted in an intensified development of vaccines. Antigens used for vaccination comprise a wide variety of macromolecules including glycoproteins, lipopolysaccharides, and complex carbohydrates. For all of these antigens the sugar composition plays a crucial role for immunogenicity and protective efficacy of the vaccine.

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During the last decade, enormous progress regarding knowledge about composition and properties of human milk (HM) has been made. Besides nutrition, the three macro-nutrients: proteins, lipids, and carbohydrates combine a large variety of properties and functions. Especially, complex oligosaccharides emerge as important dietary factors during early life with multiple functions.

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