Enzymatic determination of pyrroloquinoline quinone using crude membranes from Escherichia coli

✍ Scribed by Otto Geiger; Helmut Görisch

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 540 KB
• Volume: 164
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(87)90513-6

✦ Synopsis

Escherichia coli K-12 (ATCC 10 798) contains only the apoform of membrane-bound D-glucose dehydrogenase (pyrroloquinoline quinone-dependent). Crude membrane preparations or even crude cell extracts are suitable for a sensitive determination of pyrroloquinoline quinone under appropriate conditions. The apoform of D-glucose dehydrogenase from E. coli is reconstituted with pyrroloquinoline quinone to the holoenzyme in the presence of Mg2+ and assayed for glucose dehydrogenase activity. By increasing the time of reconstitution it is possible to detect minute amounts of about 20 pg pyrroloquinoline quinone.