Tumor promoting phorbol-ester derivatives increase ornithine decarboxylase activity and polyamine biosynthesis in the liver of the rat and mouse

1982 ◽  
Vol 3 (7) ◽  
pp. 751-755 ◽  
Author(s):  
Craig V. Byus ◽  
Richard A. Weiner
Keyword(s):  
Ornithine Decarboxylase ◽  
Phorbol Ester ◽  
Decarboxylase Activity ◽  
Polyamine Biosynthesis ◽  
Ornithine Decarboxylase Activity

scholarly journals Role of pyridoxal phosphate in mammalian polyamine biosynthesis. Lack of requirement for mammalian S-adenosylmethionine decarboxylase activity

1977 ◽  
Vol 166 (1) ◽  
pp. 81-88 ◽  
Author(s):  
A E Pegg
Keyword(s):  
Ornithine Decarboxylase ◽  
Pyridoxal Phosphate ◽  
Vitamin B ◽  
Decarboxylase Activity ◽  
Deficient Diet ◽  
Polyamine Biosynthesis ◽  
Adenosylmethionine Decarboxylase ◽  
Ornithine Decarboxylase Activity

1. Polyamine concentrations were decreased in rats fed on a diet deficient in vitamin B-6. 2. Ornithine decarboxylase activity was decreased by vitamin B-6 deficiency when assayed in tissue extracts without addition of pyridoxal phosphate, but was greater than in control extracts when pyridoxal phosphate was present in saturating amounts. 3. In contrast, the activity of S-adenosylmethionine decarboxylase was not enhanced by pyridoxal phosphate addition even when dialysed extracts were prepared from tissues of young rats suckled by mothers fed on the vitamin B-6-deficient diet. 4. S-Adenosylmethionine decarboxylase activities were increased by administration of methylglyoxal bis(guanylhydrazone) (1,1′-[(methylethanediylidine)dinitrilo]diguanidine) to similar extents in both control and vitamin B-6-deficient animals. 5. The spectrum of highly purified liver S-adenosylmethionine decarboxylase did not indicate the presence of pyridoxal phosphate. After inactivation of the enzyme by reaction with NaB3H4, radioactivity was incorporated into the enzyme, but was not present as a reduced derivative of pyridoxal phosphate. 6. It is concluded that the decreased concentrations of polyamines in rats fed on a diet containing vitamin B-6 may be due to decreased activity or ornithine decarboxylase or may be caused by an unknown mechanism responding to growth retardation produced by the vitamin deficiency. In either case, measurements of S-adenosylmethionine decarboxylase and ornithine decarboxylase activity under optimum conditions in vitro do not correlate with the polyamine concentrations in vivo.

Rotenoids and chalcones from Mundulea sericea that inhibit phorbol ester-induced ornithine decarboxylase activity

1994 ◽  
Vol 36 (6) ◽  
pp. 1523-1526 ◽  
Author(s):  
Lumonadio Luyengi ◽  
Ik-Soo Lee ◽  
Woongchon Mar ◽  
Harry H.S. Fong ◽  
John M. Pezzuto ◽  
...  
Keyword(s):  
Ornithine Decarboxylase ◽  
Phorbol Ester ◽  
Decarboxylase Activity ◽  
Ornithine Decarboxylase Activity

scholarly journals Amine-specificity of the inactivating ornithine decarboxylase modification in Physarum polycephalum

1982 ◽  
Vol 205 (3) ◽  
pp. 551-557 ◽  
Author(s):  
J L A Mitchell ◽  
G K Mitchell ◽  
D D Carter
Keyword(s):  
Ornithine Decarboxylase ◽  
Translational Control ◽  
Feedback Mechanism ◽  
Decarboxylase Activity ◽  
Polyamine Biosynthesis ◽  
Polyamine Analogues ◽  
Ornithine Decarboxylase Activity ◽  
Sensitivity Studies

The enzyme catalysing the polyamine-stimulated modification of Physarum ornithine decarboxylase in vivo was partially purified and its activity on purified ornithine decarboxylase was examined with respect to its specificity for various amines. Spermidine, spermine and several polyamine analogues strongly promoted this reaction in vitro (apparent Km in the 0.1-0.5 mM range), whereas putrescine (apparent Km 5.33 mM) and several related diamines were not nearly as effective. In agreement with this, sensitivity studies performed in vivo also suggested that cellular spermidine, and not putrescine, is critical in modulating ornithine decarboxylase activity by this post-translational control. Unlike putrescine, or other diamines, 1,3-diaminopropane demonstrated a functional similarity to the polyamines in stimulating this reaction. This study has demonstrated a method whereby non-physiological amines capable of depressing ornithine decarboxylase activity by this natural feedback mechanism can be readily identified for further evaluation of their potential use in the experimental and medical control of polyamine biosynthesis.

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