TY - JOUR A1 - Neumann-Schaal, Meina A1 - Messerschmidt, Katrin A1 - Grenz, Nicole A1 - Heilmann, Katja T1 - Use of antibody gene library for the isolation of specific single chain antibodies. by ampicillin-antigen conjugates JF - Immunology letters : an international journal providing for the rapid publication of short reports in immunology N2 - Isolation of recombinant antibodies from antibody libraries is commonly performed by different molecular display formats including phage display and ribosome display or different cell-surface display formats. We describe a new method which allows the selection of Escherichia coil cells producing the required single chain antibody by cultivation in presence of ampicillin conjugated to the antigen of interest. The method utilizes the neutralization of the conjugate by the produced single chain antibody which is secreted to the periplasm. Therefore, a new expression system based on the pET26b vector was designed and a library was constructed. The method was successfully established first for the selection of E. coli BL21 Star (DE3) cells expressing a model single chain antibody (anti-fluorescein) by a simple selection assay on LB-agar plates. Using this selection assay, we could identify a new single chain antibody binding biotin by growing E. coil BL21 Star (DE3) containing the library in presence of a biotin-ampicillin conjugate. In contrast to methods as molecular or cell surface display our selection system applies the soluble single chain antibody molecule and thereby avoids undesired effects, e.g. by the phage particle or the yeast fusion protein. By selecting directly in an expression strain, production and characterization of the selected single chain antibody is possible without any further cloning or transformation steps. KW - Single chain antibody KW - Selection method KW - Anti-biotin antibody KW - Naive single chain library Y1 - 2013 U6 - https://doi.org/10.1016/j.imlet.2013.02.005 SN - 0165-2478 VL - 151 IS - 1-2 SP - 39 EP - 43 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Messerschmidt, Katrin A1 - Neumann-Schaal, Meina A1 - Heilmann, Katja T1 - Use of antibody gene library for the isolation of specific single chain antibodies by ampicillinantigen conjugates T2 - The journal of immunology Y1 - 2013 SN - 0022-1767 VL - 190 PB - American Assoc. of Immunologists CY - Bethesda ER - TY - JOUR A1 - Badalyan, Artavazd A1 - Neumann-Schaal, Meina A1 - Leimkühler, Silke A1 - Wollenberger, Ursula T1 - A Biosensor for aromatic aldehydes comprising the mediator dependent PaoABC-Aldehyde oxidoreductase JF - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis N2 - A novel aldehyde oxidoreductase (PaoABC) from Escherichia coli was utilized for the development of an oxygen insensitive biosensor for benzaldehyde. The enzyme was immobilized in polyvinyl alcohol and currents were measured for aldehyde oxidation with different one and two electron mediators with the highest sensitivity for benzaldehyde in the presence of hexacyanoferrate(III). The benzaldehyde biosensor was optimized with respect to mediator concentration, enzyme loading and pH using potassium hexacyanoferrate(III). The linear measuring range is between 0.5200 mu M benzaldehyde. In correspondence with the substrate selectivity of the enzyme in solution the biosensor revealed a preference for aromatic aldehydes and less effective conversion of aliphatic aldehydes. The biosensor is oxygen independent, which is a particularly attractive feature for application. The biosensor can be applied to detect contaminations with benzaldehyde in solvents such as benzyl alcohol, where traces of benzaldehyde in benzyl alcohol down to 0.0042?% can be detected. KW - Aldehyde oxidoreductase KW - Benzaldehyde KW - Biosensor KW - Aromatic aldehydes KW - Molybdenum cofactor Y1 - 2013 U6 - https://doi.org/10.1002/elan.201200362 SN - 1040-0397 VL - 25 IS - 1 SP - 101 EP - 108 PB - Wiley-VCH CY - Weinheim ER - TY - THES A1 - Neumann-Schaal, Meina T1 - Studies on the mechanism molybdenum cofactor sulfuration and insertion into rhodobacter capsulatus xanthine dehydrogenase Y1 - 2007 CY - Potsdam ER -