modified L-aspartic acid residue S-(aspart-4-yloxy) thiocarbonate 190.9888458251953125 191.160003662109375 75.9618988037109375 76.0800018310546875 4-aspartyloxysulfanylcarbonate D C 5 H 5 N 1 O 5 S 1 none AspOSCO2H This modification was originally observed in an Entamoeba histolytica enzyme expressed in Escherichia coli. It was not chemically confirmed or characterized. It did not appear in a later model at higher resolution by the same group. This is a deprecated entry in RESID. It probably does not occur naturally [JSG]. S-(aspart-4-yloxy) thiocarbonate A protein modification that effectively converts an L-aspartic acid residue to S-(aspart-4-yloxy) thiocarbonate. O-carboxysulfanyl-4-oxo-L-homoserine (2S)-2-amino-4-(carboxysulfanyl)oxy-4-oxobutanoic acid PSI-MOD hypothetical MOD:01178 C 1 O 2 S 1