Electrochemical detection of transketolase activity using a tyrosinase biosensor

Marta Sanchez-Paniagua Lopez , Franck Charmantray (1) , Virgil Hélaine (1) , Laurence Hecquet (1) , Christine Mousty (2)

1 SEESIB - Synthèse et étude de systèmes à intêret biologique
2 LMI - Laboratoire des Matériaux Inorganiques

This paper proposes a new concept of transketolase (TK) activity profiling. A tyrosinase (PPO) biosensor, based on the immobilization of this enzyme in a Mg2Al-Cl layered double hydroxide, was developed for the amperometric detection of N-acetyl-l-tyrosine ethyl ester monohydrate (N-Ac-Tyr-OEt) at −0.2 V. This compound was released during an enzymatic reaction catalyzed by TK with N-acetyl-O-(2R, 3S, 5-trihydroxy-4-oxopentyl)-l-tyrosine ethyl ester used as donor substrate. This tyrosinase biosensor was optimized for the detection of TK activity, including PPO optimum substrate concentration, electrolyte nature, pH, and influence of bovine serum albumin (BSA). It was found that N-Ac-Tyr-OEt release is dependent on TK concentration (U/mL) in the electrolyte medium. These results demonstrate the sensitivity and specificity of the tyrosinase biosensor designed for in vitro detection of TK activity, which is known to be involved in several diseases.

Mots clés: PPO; Biosensor; Transketolase; Tyrosine; Layered double hydroxides; Amperometry

Domaines: Chimie

Marta Sanchez-Paniagua Lopez, Franck Charmantray, Virgil Hélaine, Laurence Hecquet, Christine Mousty. Electrochemical detection of transketolase activity using a tyrosinase biosensor. Biosensors and Bioelectronics, 2010, 26, pp.139-143. ⟨10.1016/j.bios.2010.05.023⟩. ⟨hal-00530536⟩