Have you checked the dictionary cif calls them L-peptide? Eleanor The header should look like this.. # data_comp_list loop_ _chem_comp.id _chem_comp.three_letter_code _chem_comp.name _chem_comp.group _chem_comp.number_atoms_all _chem_comp.number_atoms_nh _chem_comp.desc_level ALA ALA 'ALANINE ' L-peptide 10 5 . # On Mar 21 2012, Rajesh kumar wrote: > > Dear All, I have a structure of a protein and peptide complex, in which > peptide has modified residues ( phosphoserine and phosphothreonine). > During refinement these both gets disconnected with adjacent residues and > its hard to connect them.Could you please suggest me some options. > ThanksRajesh -- Professor Eleanor Dodson YSNL, Dept of Chemistry University of York Heslington YO10 5YW tel: 00 44 1904 328259 Fax: 00 44 1904 328266