Two endopeptidases have been characterized in Bacillus sphaericus 9602: a gamma-D-glutamyl-(L) meso-diaminopimelate endopeptidase (endopeptidase I) and a gamma-D-glutamyl-L-diaminoacid endopeptidase (endopeptidase II). They are active on the peptide moieties of some bacterial peptidoglycans. Their specificities have been studied on peptides or monomeric glycopeptides derived from peptidoglycans. Their study was attempted on dimeric and polymeric fragments of a E. coli radioactive peptidoglycan. Those compounds are specifically labelled on the meso-diaminopimelate residues and are listed below.