66 Whole cell bioluminescent biosensors for on-line processing.

G. S. SAYLER (1), M. Simpson (1), B. Applegate (1), D. Nivens (1), and S. Ripp (1).

The use of bioluminescent reporter genes is well established for monitoring the expression of both biosynthetic and catabolic operons. However, the use of bacterial luciferase gene cassettes (lux CDABE) in transcriptional gene fusions has permitted the broader development of reagent less whole cell biosensor microorganisms for on-line, real-time measurement of bioprocess activity or sensing chemical products of a specific bioprocess. This strategy has been extensively developed for environmental research, but it is also moving toward development for generalized bioprocessing. The use of whole cell, reagent-less biosensors makes continuous process monitoring practical through bioluminescent light measurement with photomultipliers and photon counting systems coupled to fiber optic probes. Often, the dynamic measurement range for concentrations of product or substrate exceeds three orders of magnitude in linear sensitivity. The most recent biosensor development is the use of the bioluminescent bioreporter (BB) organisms attached to a silicon chip integrated circuit (IC) for bioprocess light production, detection and signal processing. This chip-based biosensor, termed BBIC, has reached prototype development and has shown effectiveness in continuous operation. The BBIC technology offers new, remote, on-line process monitoring capability than may be achieved economically based on current chip fabrication techniques.