Protein-based biosensors

Corbisier, R, van der Lelie, D., Borremans, B., Provoost, A., de Lorenzo, V., Brown, N., Lloyd, J.R., Hobman, J.L., Csoregi, E., Johansson, G., and Mattiasson, B., Whole cell- and protein-based biosensors for the detection of bioavailable heavy metals in environmental samples, Anal Chim Acta, 387 (3), 235-244, 1999. 

One of the important purposes for the study of the direct electron transfer of protein is to construct the mediator-free protein-based biosensors. These biosensors can determine many small molecules like H202, 02, NO, nitrite, small organic peroxide, and so on. They also can determine glucose, alcohol, and amino acids by... 

Scognamiglio V, Staiano M, Rossi M, D Auria S. Protein-based biosensors for diabetic patients. Journal of Fluorescence 2004, 14, 491-498. 

Kostrzynska, M., Leung, K.T., Lee, H. and Trevors, J.T. (2002) Green fluorescent protein-based biosensor for detecting SOS-inducing activity of genotoxic compounds. Journal of Microbiological Methods, 48, 43-51. 

Coebisiee P, van dee Lelie D, Borremans B, Peovoost a, de Lorenzo V, Brown N, Lloyd J, Hobman j, Csoeegi E, Johannsson G and Mattiasson B (1999) Whole cell-and protein-based biosensors for the detection ofbioavailable heavy metals in environmental samples. Anal Chun Acta 387 235-244. 

The third advantage, the chemical stability of DNA aptamers, can solve the main problem of protein-based biosensors. The chemical and physical instability of protein-based biosensors is always claimed in practical use, and this limits the range of biosensor application. However, DNA is chemically stable. It is stable within the pH range 2 to 12 and is thermally renaturable Even if it is denatured at 100°C, it is refolded at room temperature. Even RNA aptamers can gain stability upon 1 modification therefore, aptamers have the potential to enhance the applicability of biosensors in practical contexts. Additionally, aptamers can be immobilized onto substrates using DNA microarray fabrication technology, and aptamer microarrays can be created. 

The data reported here indicate that not only can protein-based biosensors monitor heavy metal ions at low concentrations and across a wide concentration range, but they can provide useful information on the response of a protein to the metal, which may have a biological significance. However, the results should be interpreted with caution, as oxidation or other denaturation of the protein may alter the observed response, as was the case with MerR electrodes prepared in DTT solution compared with those prepared under nitrogen. 

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