Oat arginine decarboxylase is synthesized as a 66-kDa proenzyme, but the soluble enzyme is found in oats as a complex of 42- and 24-kDa polypeptide fragments, both derived from the 66-kDa precursor. We report here that this proteolytic cleavage is the result of a processing enzyme, distinct from arginine decarboxylase itself, that leads to activation of the arginine decarboxylase. The proteolys...

An arginine decarboxylase has been isolated from a Pseudomonas species. The enzyme is constitutive and did not appear to be repressed by a variety of carbon sources. After an approximately 40-fold purification, the enzyme appeared more similar in its properties to the Escherichia coli biosynthetic arginine decarboxylase than to the E. coli inducible (biodegradative) enzyme. The Pseudomonas argi...

Ornithine decarboxylase and arginine decarboxylase activities were measured in roots and buds of tomato (Lycopersicon esculentum Mill. cv. Pearson ms-35) and potato (Solanum tuberosum cv. Desire) plants. In both tomato and potato, the activity of ornithine decarboxylase was the highest at the root tip, decreasing proximally. The same was true for potato buds. In vegetative buds of tomato, the h...

In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to V(max), ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornith...

Polyamines are important regulators of basal cellular functions but also subserve highly specific tasks in the mammalian brain. With this respect, polyamines and the synthesizing and degrading enzymes are clearly differentially distributed in neurons versus glial cells and also in different brain areas. The synthesis of the diamine putrescine may be driven via two different pathways. In the "cl...

Polyamines (PAs) are involved in various developmental processes, especially plant flowering. Their significant influences have been established; however, the exact mechanism by which PAs regulate flowering remains unclear. To explore PA metabolism flowering, gibberellic acid (GA3, 0~2400 mg L?1) and spermidine (Spd, 0~1 mM) were applied alone or combination during early stage of flower bud for...

We find that the transcription of various ribosomal proteins can be differentially affected by polyamines and by changes in growth rates. Using strain MG1655 of Escherichia coli K-12 (F-, lambda-), we have determined the effects of polyamines and changes in growth rate on the transcription of several ribosomal genes and the polyamine-synthesizing enzymes ornithine decarboxylase (L-ornithine car...

Abbreviations: ACC: 1-Amino-cyclopropane-1-carboxylic acid ADC: arginine decarboxylase AgNO3: silver nitrate AVG: aminoethoxyvinylglycine BA: 6-benzylaminopurine DFMA: α-DL-difluromethyl arginine DFMO: α-DL-difluromethyl ornithine IAA: indole acetic acid NAA: α-naphthalene acetic acid ODC: ornithine decarboxylase PA: polyamine Put: putrescine SAM: S-adenosyl-Lmethionine STS: silver thiosulphate...