TY  - JOUR
A1  - Zhang, Shuhao
A1  - Bisterfeld, Carolin
A1  - Bramski, Julia
A1  - Vanparijs, Nane
A1  - De Geest, Bruno G.
A1  - Pietruszka, Jörg
A1  - Böker, Alexander
A1  - Reinicke, Stefan
T1  - Biocatalytically Active Thin Films via Self-Assembly of 2-Deoxy-D-ribose-5-phosphate Aldolase-Poly(N-isopropylacrylamide) Conjugates
JF  - Bioconjugate chemistry
N2  - 2-Deoxy-D-ribose-5-phosphate aldolase (DERA) is a biocatalyst that is capable of converting acetaldehyde and a second aldehyde as acceptor into enantiomerically pure mono- and diyhydroxyaldehydes, which are important structural motifs in a number of pharmaceutically active compounds. However, substrate as well as product inhibition requires a more-sophisticated process design for the synthesis of these motifs. One way to do so is to the couple aldehyde conversion with transport processes, which, in turn, would require an immobilization of the enzyme within a thin film that can be deposited on a membrane support. Consequently, we developed a fabrication process for such films that is based on the formation of DERA-poly(N-isopropylacrylamide) conjugates that are subsequently allowed to self-assemble at an air-water interface to yield the respective film. In this contribution, we discuss the conjugation conditions, investigate the interfacial properties of the conjugates, and, finally, demonstrate a successful film formation under the preservation of enzymatic activity.
Y1  - 2017
U6  - https://doi.org/10.1021/acs.bioconjchem.7b00645
SN  - 1043-1802
VL  - 29
IS  - 1
SP  - 104
EP  - 116
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Reinicke, Stefan
A1  - Fischer, Thilo
A1  - Bramski, Julia
A1  - Pietruszka, Jörg
A1  - Böker, Alexander
T1  - Biocatalytically active microgels by precipitation polymerization of N-isopropyl acrylamide in the presence of an enzyme
JF  - RSC Advances
N2  - We present a novel protocol for the synthesis of enzymatically active microgels. The protocol is based on the precipitation polymerization of N-isopropylacrylamide (NIPAm) in the presence of an enzyme and a protein binding comonomer. A basic investigation on the influence of different reaction parameters such as monomer concentration and reaction temperature on the microgel size and size distribution is performed and immobilization yields are determined. Microgels exhibiting hydrodynamic diameters between 100 nm and 1 mu m and narrow size distribution could be synthesized while about 31-44% of the enzyme present in the initial reaction mixture can be immobilized. Successful immobilization including a verification of enzymatic activity of the microgels is achieved for glucose oxidase (GOx) and 2-deoxy-d-ribose-5-phosphate aldolase (DERA). The thermoresponsive properties of the microgels are assessed and discussed in the light of activity evolution with temperature. The positive correlation of enzymatic activity with temperature for the GOx containing microgel originates from a direct interaction of the enzyme with the PNIPAm based polymer matrix whose magnitude is highly influenced by temperature.
Y1  - 2019
U6  - https://doi.org/10.1039/c9ra04000e
SN  - 2046-2069
VL  - 9
IS  - 49
SP  - 28377
EP  - 28386
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  -