Hydroxydihydroergosine, a new ergot alkaloid analogue from directed biosynthesis bySphacelia sorghi

Abstract

1257Carnosine-synthetase activity has been shown to be present in chick erythrocytesS; however, no synthetase activity was detected in rabbit reticulocytes or erythrocytes under our conditions. It may be that the enzyme lost activity prior to the time of assay, since there is a loss in enzyme activity from rat skeletal muscle shipped in this manner. It was interesting to find higher carnosine levels in rabbit reticulocytes than in rabbit erythrocytes. Mammalian reti-culocytes differ from mammalian erythrocytes in many respects s'9. Reticulocytes have the ability to synthesize globin, whereas mature erythrocytes have lost all of their ability to synthesize proteing-~k It may be that carnosine is somehow involved in RNA and/or protein synthesis in reticulocytes. Studies with inhibitors of carnosine synthesis may be useful in elucidating the physiological function of carnosine in mammalian reticulocytes.

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“…Erstaunlicherweise gelang es in Spezialfallen, chemisch nah verwandte Verbindungen anstelle von L-Prolin, dem dritten Aminosäure-Baustein aller natürlichen Ergopeptine, einbauen zu lassen. So bauten Kulturen von Sphacelia sorghi bei der Inkubation mit allo-4-Hydroxy-prolin oder cis-4-Hydroxy-prolin die beiden Verbindungen zu einem geringen Prozentsatz in das Gerüst des 9,10-Dihydro-a-ergosins em, wobei die beiden epimeren 9'-Hydroxydihydroergosine der Formel 97 entstanden [73]. Der u-Ergosinstamm C. purpurea MUT 168/2 war sogar imstande, L-Thiazolidin-4-carbonsäure anstelle von L-Prolin zu verwerten und damit 2'(3-Methyl-S'a-isobutyl-9 ' -thiaergopeptin, 98, aufzubauen [74].…”

Role of the δ 8 double bond of agroclavine in lysergic acid amide biosynthesis byClaviceps purpurea

“…The biosynthetic pathway leading to the ergot alkaloids is fairly well understood though much mechanistic detail remains un-clearL A strain of Claviceps purpurea which, as a parasite, elaborates trace amounts of dimethylallyltryptophan (1), but no ergoline alkaloids, has been shown to metabolize exogenous agroclavine (2) or lysergic acid (6) to lysergic acid amide (7) only 2. This system is therefore suitable for exploring certain aspects of the biosynthesis of the lysergyl nucleus in parasitic sclerotial tissue.…”