Pathways for methionine biosynthesis in <i>E. coli</i>, <i>P. putida</i> and <i>R. solanacearum</i>.

<p>The MetE and MetH methionine synthases catalyze the methylation of homocysteine to produce methionine, with methyltetrahydrofolate [5-methyl tetrahydropteroyltri-L-glutamate] being the methyl group donor <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036877#pone.0036877-Figge1" target="_blank">[13]</a>.