BACKGROUND Cigarette smoking was shown to delay gastric ulcer healing and reduce synthesis of mucus, which is important for gastric ulcer protection and healing. Polyamines are important in these processes. AIMS To study the effects of cigarette smoking on the synthesis of mucus and to investigate if such an effect is acting by interference with the polyamine pathway. METHODS Gastric mucosa...

The effect of various sulfhydryl (SH)-specific reagents on arginine-ornithine antiport activity in membrane vesicles of Lactococcus lactis was studied. Little or no inhibition of arginine-ornithine exchange was observed with maleimides and arsenicals. HgC! 2 and the organic mercurials p-chloromercuribenzene sulfonate (pCMBS), p-chloromercuribenzoate (pCMB), and O-(3-hydroxymercuri-2-methoxyprop...

A multiplex PCR method, aimed at the detection of genes associated with biogenic amine production, identified the odc gene encoding ornithine decarboxylase in 1 of 15 strains of Staphylococcus epidermidis. The ability of the positive strain, S. epidermidis 2015B, to produce putrescine in vitro was demonstrated by high-performance liquid chromatography (HPLC). In this strain, the odc gene was de...

The glutamic acid moiety of N-[4-[3-(2,4-diamino-7H-pyrrolo[2,3-d]pyrimidin-5-yl)propyl]benzoyl]-L-g lutamic acid (1b, TNP-351) and the related compound (1a), was replaced with various N(omega)-acyl-, sulfonyl-, carbamoyl- and aryl-2,omega-diaminoalkanoic acids, and the inhibitory effects of the resulting products (9, 11, 14, 18, 21, 23, 25, 30, 36) on dihydrofolate reductase (DHFR), the growth...

Topical application of retinole acid to mouse skin led to a dramatic inhibition of phorbol ester (12-O-tetradecanoylphorbol-13-acetate)-induced epidermal ornithine decarboxylase (EC 4.1.1.17) activity, an event proposed to be essen tial for tumor promotion. The degree of inhibition was de pendent on the dose and time of application of retinoic acid. In contrast, treatment with retinoic acid did...

Enriched fractions of mature and immature neutrophil granulocytes, isolated from guinea pig bone marrow, were assayed for ornithine decarboxylase activity and polyamine content. The results show that immature granulocytes contain at least ten times more ornithine decarboxylase activity and two times more spermidine than mature granulocytes. The incorporation of 14C-ornithine into putrescine and...

When tested for ornithine and arginine decarboxylases, pyrrolizidine alkaloid-bearing Senecio riddellii, S. longilobus (Compositae), and Crotalaria retusa (Leguminosae) plants exhibited only ornithine decarboxylase activity. This contrasts with previous studies of four species of pyrrolizidine alkaloid-bearing Heliotropium (Boraginaceae) in which arginine decarboxylase activity was very high re...

Studies of Leishmania donovani have shown that both ornithine decarboxylase and spermidine synthase, two enzymes of the polyamine biosynthetic pathway, are critical for promastigote proliferation and required for maximum infection in mice. However, the importance of arginase (ARG), the first enzyme of the polyamine pathway in Leishmania, has not been analyzed in L. donovani To test ARG function...

Four patients with gyrate atrophy of the choroid and retina were studied, all of whom exhibited the hyperornithinemia characteristic of this disorder. Elevated plasma histidine and diminished plasma lysine and branched-chain amino acids were also noted. The renal clearances of these four amino acids were not sufficiently elevated to explain their low plasma levels. In one subject, an arginine-d...