Mr. Phelps et al., AN AUTOCLAVABLE GLUCOSE BIOSENSOR FOR MICROBIAL FERMENTATION MONITORING AND CONTROL, Biotechnology and bioengineering, 46(6), 1995, pp. 514-524
The design, construction, and characterization of a prototype-regenera
ble glucose biosensor based on the reversible immobilization of glucos
e oxidase (GOx) using cellulose binding domain (CBD) technology is des
cribed. GOx, chemically linked to CBD, is immobilized by binding to a
cellulose matrix on the sensor-indicating electrode. Enzyme immobiliza
tion can be reversed by perfusing the cellulose matrix with a suitable
eluting solution. An autoclavable sensor membrane system is employed
which is shown to be practical for use in real microbial fermentations
. The prototype glucose biosensor was used without failure or deterior
ation during fed-batch fermentations of Escherichia coli reaching a ma
ximum cell density of 85 g (dry weight)/L. Medium glucose concentratio
n based on sensor output correlated closely with off-line glucose anal
ysis and was controlled manually at 0.44 +/- 0.2 g/L for 2 h based on
glucose sensor output. The sensor enzyme component could be eluted and
replaced without interrupting the fermentation. To our knowledge, no
other in situ biosensor has been used for such an extended period of t
ime in such a high-cell-density fermentation. (C) 1995 John Wiley & So
ns, Inc.