Membrane Entrapped Saccharomyces cerevisiae in a Biosensor-like Device as a Generic Rapid Method to Study Cellular Metabolism

M MARTÍNEZ; A HILDING OHLSSON; A. A. VIALE; EDUARDO CORTON

JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS

ELSEVIER SCIENCE BV

Lugar: Londres; Año: 2007 vol. 70 p. 455 - 464

0165-022X

We describe a new, faster and convenient method to study some metabolic characteristics—by the successful application of immobilized yeast cells (S. cerevisiae) in a microbial biosensor-like device. Microbial biosensors consist of microorganisms immobilized on the surface of amembrane or in a gel, in close contact with a transducer. Almost all works published to date have used biosensors for analyses in which a concentration-related property of the external medium is measured. A different approach is presented here; we have successfully used S. cerevisiaeand a carbon dioxide electrode as the main components of a biosensor-like device, used as a proof of concept, for a system useful to characterize metabolic parameters of the microbial cells immobilized on a carbon dioxide electrode. The biosensor-like device we are presenting allows us to calculate Michaelis–Menten parameters related to the kinetics of transport and degradation of several carbohydrates (i.e., glucose, fructose, galactose, sucrose and xylose, with Km(app) of 6.0, 5.8, 0.9, 2.0, and 147 mM, respectively), and the study of the kinetics of expression of nonconstitutive proteins related to the transport and degradation of galactose.