Link to Pubmed [PMID] – 3153617
Microbiol. Sci. 1987 Sep;4(9):258, 260-2
Amino acid sequence similarities detected between enzymes involved in methionine and cysteine biosynthesis, and between enzymes involved in the threonine, isoleucine and tryptophan biosynthetic pathways allow an experimental investigation of the mechanisms whereby metabolic pathways have evolved.