Klein, Andreas R.;
Berk, Holger;
Purwantini, Endang;
Daniels, Lacy;
Thauer, Rudolf K.
Si‐Face Stereospecificity at C5 of Coenzyme F420 for F420‐Dependent Glucose‐6‐Phosphate Dehydrogenase from Mycobacterium smegmatis and F420‐Dependent Alcohol Dehydrogenase from Methanoculleus thermophilicus
You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Si‐Face Stereospecificity at C5 of Coenzyme F420 for F420‐Dependent Glucose‐6‐Phosphate Dehydrogenase from Mycobacterium smegmatis and F420‐Dependent Alcohol Dehydrogenase from Methanoculleus thermophilicus
Contributor:
Klein, Andreas R.;
Berk, Holger;
Purwantini, Endang;
Daniels, Lacy;
Thauer, Rudolf K.
Description:
<jats:p>Coenzyme F<jats:sub>420</jats:sub> is a 5‐deazaflavin. Upon reduction, 1,5‐dihydro‐coenzyme F<jats:sub>420</jats:sub> is formed with a prochiral center at C5. In this study we report that the F<jats:sub>420</jats:sub>‐dependent glucose‐6‐phosphate dehydrogenase from <jats:italic>Mycobacterium smegmatis</jats:italic> and the F<jats:sub>420</jats:sub>‐dependent alcohol dehydrogenase from <jats:italic>Methanoculleus thermophilicus</jats:italic> are <jats:italic>Si</jats:italic> ‐face stereospecific with respect to C5 of the 5‐deazaflavin. These results were obtained by following the stereochemical course of the reversible incorporation of <jats:sup>3</jats:sup>H into F<jats:sub>420</jats:sub> from tritium‐labeled substrates. Our findings bring to eight the number of coenzyme‐F<jats:sub>420</jats:sub>‐dependent enzymes shown to be <jats:italic>Si</jats:italic> ‐face stereospecific. No F<jats:sub>420</jats:sub>‐dependent enzyme with <jats:italic>Re</jats:italic> ‐face stereospecificity is known. This is noteworthy since coenzyme F<jats:sub>420</jats:sub> is functionally similar to pyridine nucleotides for which both <jats:italic>Si</jats:italic> ‐face and <jats:italic>Re</jats:italic> ‐face specific enzymes have been found.</jats:p>