Ernst Bayer

Bio: Ernst Bayer is an academic researcher from University of Tübingen. The author has contributed to research in topics: Capillary electrophoresis & Peptide synthesis. The author has an hindex of 55, co-authored 449 publications receiving 12716 citations. Previous affiliations of Ernst Bayer include Bayer & ETH Zurich.

Rapid gas chromatographic separation of amino acid enantiomers with a novel chiral stationary phase.

Abstract: The use of novel polysiloxanes as stationary phase carrying chiral groups enables the separation of most amino acid enantiomers in a much shorter time than ever reported previously. Phases of this type exhibit very low volatility and high thermal stability and may be used in routine analysis with open tubular columns ant temperatures of at least 175 degrees C. Most protein amino acids are separated in a temperature program between 90 and 175 degrees C, thus obviating the need for multiple injections. Resolution factors are somewhat lower than those of other diamide phases containing the L-valine t-butyl-amide group, but are sufficient for resolution of almost all protein amino acid enantiomers.

Stoffwechselprodukte von Mikroorganismen. 98. Mitteilung. Phosphinothricin und Phosphinothricyl-Alanyl-Alanin

Abstract: From cultures of Streptomyces viridochromogenes a new antibiotic, phosphinothricylalanyl-alanine, has been isolated. The new amino acid phosphinothricin is 2-amino-4-methyl-phosphino-butyric acid, its structure is confirmed by synthesis. The tripeptide is highly active against Gram-positive and Gram-negative bacteria and against the fungus Botrytis cinerea. Phosphinothricin is an active glutamine synthetase inhibitor.

Towards the Chemical Synthesis of Proteins

Abstract: The chemical total synthesis of proteins using solid supports has made great progress. It is therefore becoming a reality what E. Fischer already predicted in 1902: “I foresee the time when physiological chemistry… is able to prepare synthetic enzymes.” The synthesis of peptides of up to 20 amino acids by the well-established solid-phase procedure on polymeric supports (SPPS) has made great progress through the development of newer supports. At the same time, methods have emerged which facilitate the separation and characterization of peptides, thus allowing optimization of the synthesis of pure materials. The new supports which enable one to synthesize peptides by a rapid continuous flow procedure are characterized by hydrophilicity, beads of approximately equal size, similar swelling properties in the solvents used for peptide synthesis, and stability at high pressure. With graft copolymers of weakly cross-linked polystyrene and linear polyethylene glycol (PEG), the synthetic cycle for coupling of one amino acid can routinely be reduced to 10–20 min with a concomitant higher yield. With beads of monodispersed graft copolymer of 10 μm diameter, a synthetic cycle can, in principle, be shortened to 1–5 min. By utilizing this high-speed solid-phase procedure, larger peptides up to the size of proteins could also be prepared in a few hours. With newer mass spectroscopic methods such as ion-spray mass spectrometry, peptides of up to a molecular mass of 100 kDa can be characterized, and with the advent of capillary electrophoresis, another very efficient separation tool, besides HPLC, is at our disposal.

Bcl-XL protects pancreatic adenocarcinoma cells against CD95- and TRAIL-receptor-mediated apoptosis.

Abstract: In this study we sought to clarify the role of the proapoptotic potential of mitochondria in the death pathway emanating from the TRAIL (APO-2L) and CD95 receptors in pancreatic carcinoma cells. We focused on the role of the Bcl-2 family member Bcl-XL, using three pancreatic carcinoma cell lines as a model system, two of which have high (Panc-1, PancTuI) and one has low (Colo357) Bcl-XL expression. In these cell lines, the expression of Bcl-XL correlated with sensitivity to apoptosis induced by TRAIL or anti-CD95. Flow cytometric analysis revealed cell surface expression of TRAIL-R1 and TRAIL-R2 on PancTuI and Colo357, and TRAIL-R2 on Panc-1 cells. In Colo357 cells retrovirally transduced with Bcl-XL, caspase-8 activation in response to treatment with TRAIL or anti-CD95 antibody was not different from parental cells and EGFP-transfected controls, however, apoptosis was completely suppressed as measured by the mitochondrial transmembrane potential deltapsim, caspase-3 activity (PARP cleavage) and DNA-fragmentation. Inhibition of Bcl-XL function by overexpression of Bax or administration of antisense oligonucleotides against Bcl-XL mRNA resulted in sensitization of Panc-1 cells to TRAIL and PancTuI cells to anti-CD95 antibody-induced cell death. The results show that Bcl-XL can protect pancreatic cancer cells from CD95- and TRAIL-mediated apoptosis. Thus, in these epithelial tumour cells the mitochondrially mediated 'type II' pathway of apoptosis induction is not only operative regarding the CD95 system but also regarding the TRAIL system.

Solid phase peptide synthesis utilizing 9‐fluorenylmethoxycarbonyl amino acids

Abstract: 9-Fluorenylmethoxycarbonyl (Fmoc) amino acids were first used for solid phase peptide synthesis a little more than a decade ago. Since that time, Fmoc solid phase peptide synthesis methodology has been greatly enhanced by the introduction of a variety of solid supports, linkages, and side chain protecting groups, as well as by increased understanding of solvation conditions. These advances have led to many impressive syntheses, such as those of biologically active and isotopically labeled peptides and small proteins. The great variety of conditions under which Fmoc solid phase peptide synthesis may be carried out represents a truly "orthogonal" scheme, and thus offers many unique opportunities for bioorganic chemistry.

Sustainable biochar to mitigate global climate change

Abstract: Production of biochar (the carbon (C)-rich solid formed by pyrolysis of biomass) and its storage in soils have been suggested as a means of abating climate change by sequestering carbon, while simultaneously providing energy and increasing crop yields. Substantial uncertainties exist, however, regarding the impact, capacity and sustainability of biochar at the global level. In this paper we estimate the maximum sustainable technical potential of biochar to mitigate climate change. Annual net emissions of carbon dioxide (CO 2 ), methane and nitrous oxide could be reduced by a maximum of 1.8 Pg CO 2 -C equivalent (CO 2 -C e ) per year (12 % of current anthropogenic CO 2 -C e emissions; 1 Pg = 1 Gt), and total net emissions over the course of a century by 130 Pg CO 2 -C e , without endangering food security, habitat or soil conservation. Biochar has a larger climate-change mitigation potential than combustion of the same sustainably procured biomass for bioenergy, except when fertile soils are amended while coal is the fuel being offset.