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Updated: Aug 8, 2026

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Qualitative and Quantitative Assays for Detection and Characterization of Protein Antimicrobials
Published on: April 10, 2016
Possible errors in quantitative determination of phenylalanine ammonia-lyase activity by spectrophotometric methods
1Institute of Horticulture, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel.
Plant Physiology
|February 1, 1973
Abstract:
A possible error in spectrophotometric determination of cinnamate, the product of phenylalanine ammonia-lyase activity, using nonpurified protein extracts has been shown.Under optimal conditions for phenylalanine ammonia-lyase activity, with borate buffer and in the presence of alpha-keto acids, phenylpyruvate is produced and its enol tautomer-borate complex formed, strongly absorbs at 290 nanometers.
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