Use of Bacterial -Glutamyltranspeptidase for Enzymatic Synthesis of -D-Glutamyl Compounds

An enzymatic method for synthesizing various -D-glutamyl compounds efficiently and stereospecifically involving bacterial -glutamyltranspeptidase (EC 2.3.2.2) with D-glutamine as a -glutamyl donor was developed. With D-glutamine as a -glutamyl donor instead of L-glutamine in -glutamyltaurine synthesis, byproducts such as -glutamylglutamine and -glutamyl-glutamyltaurine were not synthesized and the yield of -glutamyltaurine dramatically increased from 25 to 71%. It was also shown that the purification could be simplified without these -glutamyl by-products. The possibility of synthesizing various -D-glutamyl compounds was also shown.