N(alpha)-formyl-L-methionyl-L-alanyl-L-serine + H2O => L-alanyl-L-serine + N(alpha)-formyl-L-methionine
n(alpha)-formyl-l-methionyl-l-alanyl-l-serine + h2o => l-alanyl-l-serine + n(alpha)-formyl-l-methionine