Methionine-tRNA ligase (EC 6.1.1.10) catalyzes the chemical reaction: ATP + L-methionine + tRNAMet <--> AMP + diphosphate + L-methionyl-tRNAMet The 3 substrates of this enzyme are ATP, L-methionine, and tRNA(Met), whereas its 3 products are AMP, diphosphate, and L-methionyl-tRNA(Met). This enzyme participates in 3 metabolic pathways: methionine metabolism, selenoamino acid metabolism, and aminoacyl-trna biosynthesis.