“…For the groups (HO)(O)PH and HOOC, the differences are less pronounced, and aminophosphinic acids ( I , R = Alk, X = H) are considered to be closer analogues of natural amino acids [4,5]. For example, the phosphinic analogue of methionine ( I , R = CH 3 S CH 2 CH 2 , X = H) is a much better competitive inhibitor of enzymic aminoacylation of tRNA and it is a substrate of the ATP–PP i exchange reaction, the first stage of this process [4]. The phosphinic analogues of aspartic ( I , R = HOOCCH 2 , X = H) and glutamic ( I , R = HOOCCH 2 CH 2 , X = H) acids are good substrates of transformation of aldimine form to ketamino form of aspartate aminotransferase [6].…”