A protein biosensor for lactate.

S D'Auria; Z Gryczynski; I Gryczynski; M Rossi; J R Lakowicz

doi:10.1006/abio.2000.4611

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PubMed · 10929812

A protein biosensor for lactate.

S D'Auria·Z Gryczynski·I Gryczynski·M Rossi·J R Lakowicz

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Abstract

Blood lactate is a clinically valuable diagnostic indicator. In this preliminary report we describe a protein biosensor for L-lactate based on beef heart lactate dehydrogenase (LDH). LDH was noncovalently labeled with 8-anilino-1-naphthalene sulfonic acid (ANS). The ANS-labeled LDH displayed an approximately 40% decrease in emission intensity upon binding lactate. This decrease can be used to measure the lactate concentration. The ANS-labeled LDH was further utilized in a new sensing format, polarization sensing, which is suitable for miniaturization to a point-of-care lactate monitor. However, temporal instability of beef heart LDH indicates the need for further protein engineering prior to development of a more robust lactate-sensing protein.

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Anilino Naphthalenesulfonates Animals Biosensing Techniques Cattle Dose-Response Relationship, Drug Fluorescent Dyes Isoenzymes L-Lactate Dehydrogenase Lactic Acid Models, Statistical Myocardium Spectrometry, Fluorescence Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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S D'Auria, Z Gryczynski, I Gryczynski, M Rossi, J R Lakowicz. 2000-07-15. A protein biosensor for lactate.. https://doi.org/10.1006/abio.2000.4611

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