Characterization of trisulfide modification in antibodies.
Trisulfides are a posttranslational modification formed by the insertion of a sulfur atom into a disulfide bond. Although reports for trisulfides in proteins are limited, we find that they are a common modification in natural and recombinant antibodies of all immunoglobulin G (IgG) subtypes. Trisulfides were detected only in interchain linkages and were predominantly in the light-heavy linkages. Factors that lead to trisulfide formation and elimination and their impact on activity and stability were investigated. The peptide mapping methods developed for characterization and quantification of trisulfides should be applicable to any antibody and can be easily adapted for other types of proteins.
Gu
Sheng
S
Biogen Idec, Cambridge, MA 02142, USA.
Wen
Dingyi
D
Weinreb
Paul H
PH
Sun
Yaping
Y
Zhang
Lihe
L
Foley
Susan F
SF
Kshirsagar
Rashmi
R
Evans
David
D
Mi
Sha
S
Meier
Werner
W
Pepinsky
R Blake
RB
D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000235:genetics; D004220:Disulfides / Q000737:chemistry*; D007074:Immunoglobulin G / Q000737:chemistry; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry; D007147:Immunoglobulin Light Chains / Q000737:chemistry; D010449:Peptide Mapping; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D013440:Sulfides / Q000737:chemistry*
D000911:Antibodies, Monoclonal; D004220:Disulfides; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D011994:Recombinant Proteins; D013440:Sulfides