The effect of methylglyoxal bis(guanylhydrazone), a substance known to inhibit putrescine-dependent S-adenosyl-l-methionine decarboxylase, on polyamine metabolism in liver and kidney was investigated. Almost complete inhibition of the incorporation of putrescine into spermidine was obtained up to 8h after administration of 80mg of methylglyoxal bis(guanylhydrazone)/kg body wt. by intraperitonea...

Polyamine uptake and metabolism were studied in cultures of normal and Rous sarcoma virus-transformed chick embryo fibroblasts. The uptake of radioactive putrescine and spermidine by the transformed cells was faster than that of the normal controls. The amount of radioactive putrescine and polyamines taken up by the transformed cells also exceeded that observed with normal fibroblasts. The intr...

The effect of 5'-deoxy-5'-S-isobutylthioadenosine (SIBA) on polyamine biosynthesis has been studied by using cultured chick embryo fibroblasts. It has been shown that the drug inhibits the uptake of [14C]putrescine and its conversion into labelled spermidine or spermine. The inhibitory effect is reversed by removing the inhibitor after exposing the cells to the drug for 24 h. SIBA also caused a...

Polyamine synthesis and accumulation was studied in several species of developing sea urchins. Most striking is the presence in the gametes of a large amount of spermine, with low amounts of putrescine and spermidine. This contrasts with the pattern of polyamines present in both micro-organisms and mammals. Micro-organisms contain mainly putrescine and spermidine and adult mammalian tissues usu...

We have reported that a single injection of 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)2D3), the active form of vitamin D3, into vitamin D-deficient chicks produces a marked increase in the formation of duodenal putrescine by two pathways, one from ornithine and one from spermidine (Shinki, T., Takahashi, N., Kadofuku, T., Sato, T., and Suda, T. (1985) J. Biol. Chem. 260, 2185-2190). In this...

PUT cells were selected from the XD line of cultured tobacco cells (Nicotiana tabacum L. cv. Xanthi-nc) for the ability to utilize putrescine as sole nitrogen source. Previous work had indicated that hydroxycinnamoylputrescines (principally caffeoylputrescine) and 4-amino-n-butyric acid (GABA) are obligatory intermediates in the assimilation of putrescine by PUT cells. The apparent absence in t...

Plants, in general, are put to various kinds of stress, biotic and abiotic, both natural and manmade. Infestation by insect pests and diseases, and extreme conditions such as salinity, temperature, etc., as well as heavy metal contamination affect their growth performance. Here, we studied the impact of salinity and heavy metal pollution on the growth performance of Indian Mustard Brassica junc...

Oral administration of 1 ml of 3.42 M NaCl solution to rats induced spermidine/spermine N 1-acetyltransferase (SSAT) activity in gastric mucosa as well as ornithine decarboxylase (ODC) activity. SSAT activity increased and peaked at 5 h and again at 7 h, whereas ODC activity peaked at 6 h. SSAT mRNA also increased after 3.42 M NaCl administration to an extent similar to the increase in SSAT act...

The Puu pathway is a putrescine utilization pathway involving gamma-glutamyl intermediates. The genes encoding the enzymes of the Puu pathway form a gene cluster, the puu gene cluster, and puuP is one of the genes in this cluster. In Escherichia coli, three putrescine importers, PotFGHI, PotABCD, and PotE, were discovered in the 1990s and have been studied; however, PuuP had not been discovered...