TY - JOUR
T1 - Co-activation of antibody-responsive, enzymatic sensors by a recombinant scfv antibody fragment produced in E. coli
AU - Alcalá, Pilar
AU - Ferrer-Miralles, Neus
AU - Feliu, Jordi X.
AU - Villaverde, Antonio
PY - 2002/10/1
Y1 - 2002/10/1
N2 - The biophysical nature of the signal transduction in enzymatic biosensors through which the paratope-epitope interaction enhances enzyme activity, is essentially unknown. Fab fragments of efficiently activating antibodies are, in general, poor sensor activators suggesting that the bivalent antibody binding could contribute to the sensing process. We have cloned and produced in E. coli a recombinant SD6 scFv fragment directed against a sensing peptide, displayed on a model β-galactosidase-based biosensor. While the enzymatic response to scFv-binding is not detectable, the simultaneous presence of scFv and the poorly-activator SD6 Fab fragment results in a non-additive, efficient sensor response, enhancing the enzyme activity up to about 200%. This co-operative effect, which is also observed by combining SD6 scFv and the non-homologous anti-peptide 4C4 Fab, confirms that the enzyme up-regulation requires multiple and probably heterogeneous contacts between the sensor molecule and the analytes, but not necessarily done by bivalent molecular ligands.
AB - The biophysical nature of the signal transduction in enzymatic biosensors through which the paratope-epitope interaction enhances enzyme activity, is essentially unknown. Fab fragments of efficiently activating antibodies are, in general, poor sensor activators suggesting that the bivalent antibody binding could contribute to the sensing process. We have cloned and produced in E. coli a recombinant SD6 scFv fragment directed against a sensing peptide, displayed on a model β-galactosidase-based biosensor. While the enzymatic response to scFv-binding is not detectable, the simultaneous presence of scFv and the poorly-activator SD6 Fab fragment results in a non-additive, efficient sensor response, enhancing the enzyme activity up to about 200%. This co-operative effect, which is also observed by combining SD6 scFv and the non-homologous anti-peptide 4C4 Fab, confirms that the enzyme up-regulation requires multiple and probably heterogeneous contacts between the sensor molecule and the analytes, but not necessarily done by bivalent molecular ligands.
KW - Antigen
KW - Foot and mouth disease virus
KW - Recombinant antibody
KW - Regulable enzyme
KW - scFv
KW - β-galactosidase
U2 - https://doi.org/10.1023/A:1020371220100
DO - https://doi.org/10.1023/A:1020371220100
M3 - Article
VL - 24
SP - 1543
EP - 1551
JO - Biotechnology Letters
JF - Biotechnology Letters
SN - 0141-5492
ER -