Labeling study of avidin by modular method for affinity labeling (MoAL).
We studied the specific labeling of avidin with biotinylated modular ligand catalysts via MoAL, which we recently established. The labeling yield was found to depend on the linker length connecting the catalytic site to biotin in the modular ligand catalyst 1, and the maximum yield was obtained with 1d possessing octamethylene linker. The labeling reaction reached a maximum rate with only 4 equiv of the ligand catalyst. Presumably, all the subunits of avidin with homotetrameric structure formed a stable complex with 4 equiv of the catalyst because of the extremely high affinity. The ligand catalyst bound to avidin first catalyzed N-triazinylation of the ε-amino group of Lys111, and the resulting regenerated catalyst then catalyzed the reaction of Asp108 and CDMT.
Nakanishi
Shuichi
S
Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, Japan.
Tanaka
Hiroyuki
H
Hioki
Kazuhito
K
Yamada
Kohei
K
Kunishima
Munetaka
M
D000345:Affinity Labels / Q000737:chemistry*; D001360:Avidin / Q000737:chemistry*; D001710:Biotin / Q000737:chemistry; D019921:Biotinylation; D002384:Catalysis; D020134:Catalytic Domain; D008024:Ligands; D008722:Methods; D013329:Structure-Activity Relationship
D000345:Affinity Labels; D008024:Ligands; D001360:Avidin; D001710:Biotin