TY  - JOUR
A1  - Tiedemann, Kim
A1  - Iobbi-Nivol, Chantal
A1  - Leimkühler, Silke
T1  - The Role of the Nucleotides in the Insertion of the bis-Molybdopterin Guanine Dinucleotide Cofactor into apo-Molybdoenzymes
JF  - Molecules
N2  - The role of the GMP nucleotides of the bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor of the DMSO reductase family has long been a subject of discussion. The recent characterization of the bis-molybdopterin (bis-Mo-MPT) cofactor present in the E. coli YdhV protein, which differs from bis-MGD solely by the absence of the nucleotides, now enables studying the role of the nucleotides of bis-MGD and bis-MPT cofactors in Moco insertion and the activity of molybdoenzymes in direct comparison. Using the well-known E. coli TMAO reductase TorA as a model enzyme for cofactor insertion, we were able to show that the GMP nucleotides of bis-MGD are crucial for the insertion of the bis-MGD cofactor into apo-TorA.
KW  - bis-MGD
KW  - chaperone
KW  - molybdenum cofactor
KW  - TMAO reductase
Y1  - 2022
U6  - https://doi.org/10.3390/molecules27092993
SN  - 1420-3049
VL  - 27
SP  - 1
EP  - 15
PB  - MDPI
CY  - Basel, Schweiz
ET  - 9
ER  - 
TY  - GEN
A1  - Tiedemann, Kim
A1  - Iobbi-Nivol, Chantal
A1  - Leimkühler, Silke
T1  - The Role of the Nucleotides in the Insertion of the bis-Molybdopterin Guanine Dinucleotide Cofactor into apo-Molybdoenzymes
T2  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - The role of the GMP nucleotides of the bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor of the DMSO reductase family has long been a subject of discussion. The recent characterization of the bis-molybdopterin (bis-Mo-MPT) cofactor present in the E. coli YdhV protein, which differs from bis-MGD solely by the absence of the nucleotides, now enables studying the role of the nucleotides of bis-MGD and bis-MPT cofactors in Moco insertion and the activity of molybdoenzymes in direct comparison. Using the well-known E. coli TMAO reductase TorA as a model enzyme for cofactor insertion, we were able to show that the GMP nucleotides of bis-MGD are crucial for the insertion of the bis-MGD cofactor into apo-TorA.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1268 
KW  - bis-MGD
KW  - chaperone
KW  - molybdenum cofactor
KW  - TMAO reductase
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-561728
SN  - 1866-8372
SP  - 1
EP  - 15
PB  - Universitätsverlag Potsdam
CY  - Potsdam
ER  - 
TY  - JOUR
A1  - Tadjoung Waffo, Armel Franklin
A1  - Mitrova, Biljana
A1  - Tiedemann, Kim
A1  - Iobbi-Nivol, Chantal
A1  - Leimkühler, Silke
A1  - Wollenberger, Ulla
T1  - Electrochemical trimethylamine n-oxide biosensor with enzyme-based oxygen-scavenging membrane for long-term operation under ambient air
JF  - Biosensors : open access journal
N2  - An amperometric trimethylamine N-oxide (TMAO) biosensor is reported, where TMAO reductase (TorA) and glucose oxidase (GOD) and catalase (Cat) were immobilized on the electrode surface, enabling measurements of mediated enzymatic TMAO reduction at low potential under ambient air conditions. The oxygen anti-interference membrane composed of GOD, Cat and polyvinyl alcohol (PVA) hydrogel, together with glucose concentration, was optimized until the O-2 reduction current of a Clark-type electrode was completely suppressed for at least 3 h. For the preparation of the TMAO biosensor, Escherichia coli TorA was purified under anaerobic conditions and immobilized on the surface of a carbon electrode and covered by the optimized O-2 scavenging membrane. The TMAO sensor operates at a potential of -0.8 V vs. Ag/AgCl (1 M KCl), where the reduction of methylviologen (MV) is recorded. The sensor signal depends linearly on TMAO concentrations between 2 mu M and 15 mM, with a sensitivity of 2.75 +/- 1.7 mu A/mM. The developed biosensor is characterized by a response time of about 33 s and an operational stability over 3 weeks. Furthermore, measurements of TMAO concentration were performed in 10% human serum, where the lowest detectable concentration is of 10 mu M TMAO.
KW  - trimethylamine N-oxide
KW  - biosensor
KW  - TMAO-reductase
KW  - oxygen scavenger
KW  - immobilized enzyme
KW  - multienzyme electrode
KW  - viologen
Y1  - 2021
U6  - https://doi.org/10.3390/bios11040098
SN  - 2079-6374
VL  - 11
IS  - 4
PB  - MDPI
CY  - Basel
ER  -