Pyrroloquinoline quinone (PQQ) is a novel biofactor for which a proposition can be made for physiological importance. PQQ was first recognized as an enzyme cofactor in bacteria. It has recently been tentatively identified as a component of interstellar dust. Thus, PQQ may have been present throughout early biological conception and evolution. PQQ is also a potent plant growth factor. Consequent...

Liver fibrosis represents the consequences of a sustained wound healing response to chronic liver injuries, and its progression toward cirrhosis is the major cause of liver-related morbidity and mortality worldwide. However, anti-fibrotic treatment remains an unconquered area for drug development. Accumulating evidence indicate that oxidative stress plays a critical role in liver fibrogenesis. ...

The levels of free pyrroloquinoline quinone (PQQ) in various foods were examined by the use of gas chromatography-mass spectrometry. PQQ was extracted from the samples, after addition of [U-13C]PQQ as internal standard, with n-butanol and Sep-Pak C18 cartridges. After derivatization of PQQ with phenyltrimethylammonium hydroxide, molecular peaks at m/z 448 and 462 were used for detection of PQQ ...

Enzyme-catalyzed signal amplification was introduced to the electrochemical detection of the OH radical. In the presence of phenol as a trapping agent, glucose as a substrate, and pyrroloquinoline quinone-containing glucose dehydrogenase (PQQ-GDH) as a catalyst, the current signal for the trapping adducts (catechol and hydroquinone) produced by the hydroxylation of phenol could be amplified an...

An electrochemical sensor was developed by reconstituting pyrroloquinoline quinone (PQQ), flavin adenine dinucleotide (FAD) and L-proline dehydrogenase on gold electrode. Reversible redox peaks and low redox potential were obtained from cyclic voltammograms, proved that the attached PQQ and FAD accelerated electron communication between enzyme active site and gold electrode surface. It is expec...

Pyrroloquinoline quinone (PQQ) is an important redox-active cofactor for many bacterial dehydrogenases. It’s biosynthetic pathway involves six or seven genes, one of which is pqqB. Former studies indicated that the protein encoded by pqqB, namely PqqB, functions as a PQQ transporter. Here we report the crystal structure of PqqB from Pseudomonas putida at 2.2 Å resolution together with functiona...