Fig. 4From: Efficient production of 2H, 13C, 15N-enriched industrial enzyme Rhizopus chinensis lipase with native disulfide bondsDisulfide bond mapping of r27RCL(His)6 from P. pastoris and r27RCL from E. coli. LC–MS fragments of P. pastoris and E. coli w/o TCEP treatment a C204 [alkylated with iodoacetamide (IAM)]; b C56–C295 disulfide bond pair; c C67–C70 intra-disulfide bond peptide; d intra-disulfide bond peptide indicating C262-C271Back to article page