Table 1.

PyC structures vary by terminal amino acid, number of repeating peptide units (n = 2–11) and number of disulfide bonds (m = 1–5)

Base PyCs	Elemental formula (e.g. n = 2)	Disulfide form
(γ-Glu-Cys)n-Gly	C18H29N5O10S2	(S-S)m(γ-Glu-Cys)n-Gly
(γ-Glu-Cys)n-β-Ala	C19H31N5O10S2	(S-S)m(γ-Glu-Cys)n-β-Ala
(γ-Glu-Cys)n-Ala	C19H31N5O10S2	(S-S)m(γ-Glu-Cys)n-Ala
(γ-Glu-Cys)n	C16H26N4O9S2	(S-S)m(γ-Glu-Cys)n
(γ-Glu-Cys)n-Gln	C21H34N6O11S2	(S-S)m(γ-Glu-Cys)n-Gln
(γ-Glu-Cys)n-Ser	C19H31N5O11S2	(S-S)m(γ-Glu-Cys)n-Ser
(γ-Glu-Cys)n-Glu	C21H33N5O12S2	(S-S)m(γ-Glu-Cys)n-Glu