Details

Autor(en) / Beteiligte

• Sakai, T
• Perry, J W
• Hori, C
• Oka, T

Titel

Putrescine and the regulation of S-adenosyl-L-methionine decarboxylase in cultured mouse mammary gland

Ist Teil von

• Biochimica et biophysica acta, 1980-08, Vol.614 (2), p.577

Ort / Verlag

Netherlands

Erscheinungsjahr

1980

Quelle

MEDLINE

Beschreibungen/Notizen

• The activity of S-adenosyl-L-methionine decarboxylase (S-adenosyl-L-methionine carboxy-lyase, EC 4.1.1.50) purified from mouse mammary gland can be stimulated by physiological concentrations of putrescine (Ka = 5 x 10(-7) M). In contrast, the elevation of the intracellular concentrations of putrescine in cultured mouse mammary tissue by exogenous addition of putrescine or by cultivation of the tissue in hypotonic medium results in the decrease in both the activity and the amount of the enzyme in tissue. Conversely, the addition of 1 mM alpha-methyl ornithine, an inhibitor of ornithine decarboxylase, causes augmentation of the activity and the amount of S-adenosyl-L-methionine decarboxylase, despite its inhibitory action on insulin-stimulated increase in the concentration of putrescine. These data suggest that putrescine can act as a 'negative' regulator of the enzyme in this system.