The regularities observed here could be also applicable to bioconjugates synthesized by using self-hydrolyzing maleimides that have developed for an efficient stabilization of the bioconjugates through linker hydrolysis. and beta ( 1 ZAAGGGAAAAKPEESK 16 ) peptides, respectively. Fragments highlighted in blue as *(α/β)yn and *(α/β)bn) were manually assigned and they are derived from either the alpha of beta peptides containing a lysine and cysteine with their molecular masses increased by 71 and 98 Da, respectively. Broken lines in (b) indicate the fragment ions that were generated by the fragmentations of the pseudopeptide bond in the linker and a peptide backbone in one of the crosslinked peptides. The nomenclature for the other backbone fragment ions agrees with the reported by Schilling et al .