TY  - JOUR
A1  - Ribitsch, D.
A1  - Karl, W.
A1  - Birner-Gruenberger, R.
A1  - Gruber, K.
A1  - Eiteljoerg, I.
A1  - Remler, P.
A1  - Wieland, S.
A1  - Siegert, Petra
A1  - Maurer, Karl-Heinz
A1  - Schwab, H.
T1  - C-terminal truncation of a metagenome-derived detergent protease for effective expression in E. coli
JF  - Journal of biotechnology
N2  - Recently, a new alkaline protease named HP70 showing highest homology to extracellular serine proteases of Stenotrophomonas maltophilia and Xanthomonas campestris was found in the course of a metagenome screening for detergent proteases (Niehaus et al., submitted for publication). Attempts to efficiently express the enzyme in common expression hosts had failed. This study reports on the realization of overexpression in Escherichia coli after structural modification of HP70. Modelling of HP70 resulted in a two-domain structure, comprising the catalytic domain and a C-terminal domain which includes about 100 amino acids. On the basis of the modelled structure the enzyme was truncated by deletion of most of the C-terminal domain yielding HP70-C477.

This structural modification allowed effective expression of active enzyme using E. coli BL21-Gold as the host. Specific activity of HP70-C477 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 30 ± 5 U/mg compared to 8 ± 1 U/mg of the native enzyme. HP70-C477 was most active at 40 °C and pH 7–11; these conditions are prerequisite for a potential application as detergent enzyme. Determination of kinetic parameters at 40 °C and pH = 9.5 resulted in KM = 0.23 ± 0.01 mM and kcat = 167.5 ± 3.6 s⁻¹. MS-analysis of peptide fragments obtained from incubation of HP70 and HP70-C477 with insulin B indicated that the C-terminal domain influences the cleavage preferences of the enzyme. Washing experiments confirmed the high potential of HP70-C477 as detergent protease.
Y1  - 2010
U6  - http://dx.doi.org/10.1016/j.jbiotec.2010.09.947
SN  - 1873-4863 (E-Journal); 0168-1656 (Print)
VL  - 150
IS  - 3
SP  - 408
EP  - 416
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Wagner, H.
A1  - Schöning, Michael Josef
T1  - Automatisiertes „wafer level“-Testsystem zur Charakterisierung von siliziumbasierten Chemo- und Biosensoren
JF  - Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vorträge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in Nürnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA)
Y1  - 2010
SN  - 978-3-8007-3260-9
N1  - Fachtagung Sensoren und Messsysteme 15, 2010, Nürnberg ; Gesellschaft Mess- und Automatisierungstechnik
SP  - 89
EP  - 92
PB  - VDE Verlag
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Siqueira, José R. Jr.
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Associating biosensing properties with the morphological structure of multilayers containing carbon nanotubes on field-effect devices
JF  - Physica status solidi (a). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 781
EP  - 786
ER  - 
TY  - CHAP
A1  - Schubert, Nicole
A1  - Schöning, Michael Josef
T1  - 3. Graduiertentagung der FH Aachen
T1  - 3rd Graduate Symposium
N2  - Doktoranden der FH Aachen stellen ihre wissenschaftlichen Arbeiten aus verschiedenen Fachdisziplinen vor.
T3  - Graduiertentagung / FH Aachen - 3 
KW  - Graduiertentagung
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-3386
ER  -