Fig. 1
From: Direct conversion of theophylline to 3-methylxanthine by metabolically engineered E. coli
Methylxanthine production schemes. a Example of generalized synthetic methods adapted from [30]. b Production of 3MX (major product) and 1MX (minor product) from TP by metabolically engineered E. coli containing the ndmA and ndmD genes. Prices per gram given below the compounds are based on the Sigma Aldrich Catalog for the highest lot available (Additional file 1: Table S1)