forms cyanide as a secondary metabolite with glycine as the precursor and methionine as a stimulator. As the metabolism of glycine and methionine are interrelated by the provision of carbon-one units for the tetrahydrofolate pool by the activities of serine hydroxymethyltransferase (SHMT) and glycine cleavage enzyme (GCE), we have investigated the regulation of formation and activity of these enzymes by The synthesis of SHMT was unaffected by growth under conditions of high cyanogenesis (on a medium containing glutamate, glycine and methionine) or low cyanogenesis (on glutamate alone), nor was its synthesis affected by addition of potential end-products of carbon-one metabolism to the growth medium. The activity of GCE was very low, less than 1% of the activity of SHMT, irrespective of the growth conditions. This suggests that nearly all the carbon-one units for the tetrahydrofolate pool are supplied by the activity of SHMT; this could lead to excess formation of glycine and might explain the role of cyanogenesis. The activity of SHMT was competitively inhibited by glycine and cysteine.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error