Isolation and structure of bombesin and alytesin,two analogous active peptides from the skin of the european amphibiansBombina andAlytes

Riassunto Viene descritto l'isolamento e il chiarimento della struttura della bombesina e della alytesina due tetradecapeptidi attivi a struttura analoga presenti nella pelle fresca rispettivamente dellaBombina e dell'Alytes, anfibi europei della famiglia dei discoglossidi. I due polipeptidi manifestano azioni farmacologiche similari sulla pressione del sangue, su svariati organi a muscoli lisci, sulla secrezione gastrica e sulla glicemia.

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In part supported by grants from the Consiglio Nazionale delle Ricerche, Rome.     

Anti-gastrin immunofluorescence in the skin ofHyla crepitans and the cytochemistry of the cells involved

Zusammenfassung Mit indirekter Immunofluoreszenztechnik wird demonstriert, dass Anti-Gastrinserum (IgG-Fraktion) mit Hautzellen und mit zur Haut gehörenden Drüsen vonHyla crepitans reagiert. Diese, wahrscheinlich Caerulein enthaltenden Zellen, besitzen endokrine Eigenschaften.     

Occurrence of phyllomedusin,a physalaemin-like decapeptide,in the skin ofPhyllomedusa bicolor

Riassunto Viene descritto l'isolamento e il chiarimento della struttura della phyllomedusina, decapeptide attivo della pelle dell'anfibio sudamericanoPhyllomedusa bicolor. La phyllomedusina è apparsa strutturalmente assai vicina alla eledoisina e alla fisalemina.

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Supported n part by grants from the Consiglio Nazionale delle Ricerche, Roma.     

In vitro development ofXenopus skin glands producing 5-hydroxytryptamine and caerulein

The granular glands of amphibian skin synthesize and store a large amount of bioactive amines and peptides which are structurally similar to mammalian brain-gut peptides. To investigate the development of peptide- and amine-producing cells in the granular glands, pieces of dorsal skin taken at various stages fromXenopus laevis tadpoles were cultured, and the contents of caerulein and 5-hydroxytryptamine (5-HT) were measured. When pieces of skin from tadpoles at stages 57 to 60 (Nieuwkoop and Faber stages) were cultured in a medium containing 10% fetal calf serum (FCS medium) or one containing FCS treated with charcoal (chFCS medium), the caerulein and 5-HT levels were increased for the six days of the incubation period. The caerulein content was lower in the chFCS medium than in the FCS medium. Addition of thyroxine to the chFCS medium had no significant effect on the caerulein content. These results show that the caerulein-and 5-HT-producing cells of the granular glands can develop in a culture system with FCS- or chFCS-containing media, and suggest that FCS contains substances which are absorbed by charcoal and stimulate development of the amine- and peptideproducing cells of the glands. In a preliminary search for correlation between caerulein and 5-HT synthesis, addition of 5-hydroxytryptophan (5-HTP), a precursor to 5-HT, to the FCS medium increased 5-HT content and, conversely, caused significant decrease in caerulein content, suggesting that accumulation of caerulein in the granular glands is influenced by the amount of 5-HT synthesis. These studies indicate that this culture system is a useful model for investigating the development of peptide- and amine-producing cells.     

Isolation of biologically active alkaloids from Korean mistletoeViscum album,coloratum

Summary Anticancer activity of certain highly cytotoxic alkaloids present in Korean mistletoe has been demonstrated in experimental animals. Unlike European mistletoe, no cytotoxic proteins were found in the Korean mistletoe.This work was presented at ACS/CSJ Chemical Congress, Honolulu, Hawaii, April 1–6, 1979.We are thankful to Jerome Foundation, Los Angeles, California for a generous grant for the support of this work.     

Isolation of 5-hydroxytryptamine from the skin of the toadBufo arenarum Hensel

Zusammenfassung 5-Hydroxytryptamin wurde aus der Haut der in Argentinien häufigsten KrötenartB. arenarum Hensel isoliert und in trockenen Paratoidsekreten chromatographisch nachgewiesen.     

Isolation of the major toxic protein from the skin venom of the crested newt, Triturus cristatus

A new protein, of molecular weight 160,000, was isolated from the skin venom of the crested newt and partially characterized by bioassays and biochemical methods. This protein shows the same functional properties as the crude venom, which produces convulsions in mice and is cytotoxic.     

Isolation and characterization of biologically active lectin from Korean mistletoe, Viscum album var. Coloratum

A mistletoe lectin was isolated from water extracts of Korean mistletoe, a subspecies of Viscum album, grown on Quercus mongolica using CM-Sepharose chromatography followed by an affinity chromatography on a concanavalin A-Sepharose column. The compound proved to be a mistletoe lectin II with D-galactose and N-acetyl-D-galactosamine specificity. Matrix-assisted laser desorption time-of-flight mass spectroscopy showed it to have an average molecular mass of 62.7 kDa and to consist of two subunits of 30.6 kDa and 32.5 kDa. It was a basic protein with isoelectric points of 9.4 and 9.6 by capillary isoelectric focusing and was cytotoxic to Molt4 cell. Received 17 November 1998; received after revision 3 March 1999; accepted 3 March 1999     

Isolation of a growth-stimulating agent from human skin fibroblast cultures

Summary Cell-free supernatants were harvested from cultures of human skin fibroblasts, were applied on to DEAE-cellulose columns, and the first fraction eluted with phosphate-buffered saline contained the growth-stimulating agent. The eluted fraction was then passed through a series of amicon membranes. After passing through PM-10, the filtrate stimulated growth of bovine vascular endothelial, canine myocardial, and human mammary carcinoma cells.     

Isolation of a pharmacologically active principle from ehrlich carcinoma tumor cells

Résumé Les propriétés biologiques d'une nouvelle substance pharmacologique active isolée des cellules de l'ascite d'Ehrlich sont décrites en détail. La substance isolée contracte in vitro l'iléum du cobaye ou l'utérus du rat et relaxe l'ileum de la souris. In vivo, cette substance possède un effet hypotensif chez le chat.     

Isolation and structure of Phomin

Zusammenfassung Aus Kulturen einesPhoma spec. (Stamm S 298) (Fungi imperfecti) wurde das neue cytostatisch wirksame Antibioticum Phomin isoliert. Auf Grund seiner chemischen und physikalischen Eigenschaften wird ihm die Strukturformel1 erteilt.     

Structure and pharmacological actions of physalaemin,the main active polypeptide of the skin ofPhysalaemus fuscumaculatus

Riassunto Viene descritto il procedimento che ha permesso l'isolamento e il chiarimento della struttura chimica dellafisalemina, il principale dei polipeptidi attivi della pelle diPhysalaemus fuscumaculatus, anfibio dell'Argentina. La fisalemina, strettamente vicina all'eledoisina anche da un punto di vista chimico è, come questa, dotata di potente azione sulla muscolatura liscia vasale ed extravasale. Essa è nettamente distinguibile, mediante saggi paralleli, da tutti gli altri polipeptidi biogeni finora noti.

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Supported in part by a grant from the Consiglio Nazionale delle Richerche, Roma.     

Isolation of the optical antipode of mellein from an unidentified fungus

Zusammenfassung Ein Stoffwechselprodukt eines nicht klassifizierten Pilzes wurde als (+)-3-methyl-3,4-dihydro-8-oxyisocumarin, der optischen Antipode von Mellein, identifiziert.     

Comparative effects of caerulein,pancreozymin and secretin on pancreatic blood flow

Riassunto La registrazione del flusso ematico dell'arteria pancreaticoduodenale caudale con flussimetro elettromagnetico ha messo in evidenza una potente azione vasodilatatrice della ceruleina, della pancreozimina e della secretina, a livello del pancreas, in assenza di modificazioni della pressione arteriosa, della frequenza cardiaca e del flusso ematico femorale.     

The structure of scytonemin,an ultraviolet sunscreen pigment from the sheaths of cyanobacteria

Despite knowledge of the existence of the pigment called scytonemin for over 100 years, its structure has remained unsolved until now. This pigment, the first shown to be an effective, photo-stable ultraviolet shield in prokaryotes, is a novel dimeric molecule (molec. wt. 544) of indolic and phenolic subunits and is known only from the sheaths enclosing the cells of cyanobacteria. It is probable that scytonemin is formed from a condensation of tryptophan-and phenylpropanoid-derived subunits. The linkage between these units is unique among natural products and this novel ring structure is here termed the scytoneman skeleton. Scytonemin absorbs strongly and broadly in the spectral region 325–425 nm (UV-A-violet-blue, with an in vivo maximum at 370 nm). However, there is also major absorption in the UV-C ( _max=250nm) and UV-B (280–320 nm). The pigment has been recently shown to provide significant protection to cyanobacteria against damage by ultraviolet radiation. The pigment occurs in all phylogenetic lines of sheathed cyanobacteria and possibly represents a UV screening strategy far more ancient than that of plant flavonoids and animal melanins. How diverse organisms deal with UV radiation is considered of vital importance to global ecology.     

Amino acid composition and sequence of crinia-angiotensin,an angiotensin II-like endecapeptide from the skin of the Australian frogCrinia georgiana

Summary Methanol extracts of the skin of the Australian amphibianCrinia georgiana contain large amounts of crinia-angiotensin II, a new angiotensin II-like peptide. This differs sharply from the conventional octapeptide angiotensins II in having attached the tripeptide Ala-Pro-Gly- to the N-terminus, and having an Ile residue substituted for the Val residue at position 6 from the C-terminus. Small amounts of angiotensin-like peptides have been traced, by radioimmunoassay, in skin extracts of some otherCrinia species.Supported by grants from the Consiglio Nazionale delle Ricerche, Italy, and from the Ministry of Education, Japan.