The oscillations in phenylalanine aunnnia-lyase activity from Spirodels pelyrhiza and phenylalanine ammonia-lyase and tyrosine ammonia-lyase activities from Lemnas perpusilam disayed a circadian rhythm under continuous lght. Rhythmiclty in enzymic activity could not be detected in continuous darkness since under this condition phenylalanine ammonialyase activity remains at a fairly constantly l...

L-Phenylalanine ammonia-lyase has been purified from elicitortreated alfalfa (Medicago sativa L.) cell suspension cultures using two protocols based on different sequences of chromatofocusing and hydrophobic interaction chromatography. Three distinct forms of the intact enzyme were separated on the basis of affinity for Octyl-Sepharose, with isoelectric points in the range pH 5.1 to 5.4. The na...

An efficient enzymatic process was developed to produce optically pure D-phenylalanine through asymmetric resolution of the racemic DL-phenylalanine using immobilized phenylalanine ammonia-lyase (RgPAL) from Rhodotorula glutinis JN-1. RgPAL was immobilized on a modified mesoporous silica support (MCM-41-NH-GA). The resulting MCM-41-NH-GA-RgPAL showed high activity and stability. The resolution ...

The phosphonic analogue of L-phenylalanine, (/?)-(l-am ino-2-phenylethyl)phosphonic acid (A P E P ), inhibits buckwheat phenylalanine ammonia-lyase (PAL) com petitively with a K t value o f 1.5 |iM. The K, value for the (S)-enantiomer is 11.6 jj,M. The corresponding values for the enantiom ers of the phosphonous analogue are 35 and 205 |u.m , respectively. APEP inhibits the light-induced synthe...

Phenylketonuria (PKU) is an inborn error of amino acid metabolism caused by phenylalanine hydroxylase (PAH) deficiency. Dietary treatment has been the cornerstone for controlling systemic phenylalanine (Phe) levels in PKU for the past 4 decades. Over the years, it has become clear that blood Phe concentration needs to be controlled for the life of the patient, a difficult task taking into consi...