Article

Whole-cell-based biosensors for environmental biomonitoring and application.

National Research Laboratory on Environmental Biotechnology, Kwangju Institute of Science and Technology, 1 Oryong-dong, Puk-gu, 500-712 Gwangju, Republic of Korea.
Advances in biochemical engineering/biotechnology (impact factor: 1.64). 02/2004; 87:269-305. pp.269-305
Source: PubMed

ABSTRACT A variety of whole-cell-based biosensors has been developed using numerous native and recombinant biosensing cells. The use of reporter genes, for example bacterial luciferase and gfp, to monitor gene expression is discussed in terms of each reporters' benefits and disadvantages, including their possible use on-line, their sensitivity, the need for extra substrate, etc. All biosensing cells in use can be classified into two groups in terms of their biosensing mechanisms--constitutive expression and stress- or chemical-specific inducible expression. In this review several examples of each are presented and discussed. The use of recombinant whole-cell biosensors in the field requires three components--biosensing cells, a measurement device, and a signal-transducing apparatus, the last two depending on the first and the final applications of the system. The use of different immobilization techniques in several studies to maintain the cells and their viability is also discussed, in particular their use in the development of both high-throughput and chip-based biosensing systems. Finally the application of whole-cell-based biosensors to different environmental media, such as water, soil, and atmospheric monitoring is discussed; particular attention is given to their use for detection of various stressors, including dioxins, endocrine-disrupting chemicals, and ionizing radiation.

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Keywords

biosensing cells
 
chemical-specific inducible expression
 
chip-based biosensing systems
 
detection
 
different environmental media
 
different immobilization techniques
 
dioxins
 
endocrine-disrupting chemicals
 
extra substrate
 
final applications
 
gene expression
 
ionizing radiation
 
numerous native
 
possible use on-line
 
recombinant biosensing cells
 
recombinant whole-cell biosensors
 
reporters' benefits
 
signal-transducing apparatus
 
various stressors
 
whole-cell-based biosensors
 

Man Bock Gu