Probing the limits of Q-tag bioconjugation of antibodies.
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ABSTRACT:
SUBMITTER: Marculescu C
PROVIDER: S-EPMC6788405 | biostudies-literature | 2019 Sep
REPOSITORIES: biostudies-literature
Publications
Probing the limits of Q-tag bioconjugation of antibodies.
Marculescu Cristina C Lakshminarayanan Abirami A Gault Joseph J Knight James C JC Folkes Lisa K LK Spink Thomas T Robinson Carol V CV Vallis Katherine K Davis Benjamin G BG Cornelissen Bart B
Chemical communications (Cambridge, England) 20190901 76
Site-selective labelling of antibodies (Abs) can circumvent problems from heterogeneity of conventional conjugation. Here, we evaluate the industrially-applied chemoenzymatic 'Q-tag' strategy based on transglutaminase-mediated (TGase) amide-bond formation in the generation of 89Zr-radiolabelled antibody conjugates. We show that, despite previously suggested high regioselectivity of TGases, in the anti-Her2 Ab Herceptin™ more precise native MS indicates only 70-80% functionalization at the target ...[more]
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