Stephan Heinze

Formation of new lipoaminopeptides, acremostatins A, B, and C, by co-cultivation of Acremonium sp. Tbp-5 and Mycogone rosea DSM 12973.

Formation of new lipoaminopeptides, acremostatins A, B, and C, was observed during co-cultivation of Acremonium sp. Tbp-5 and Mycogone rosea DSM 12973. Thus, co-cultivation of microorganisms producing related products could be suggested as a suitable way towards diversification of microbial structures.

ISOLATION AND STRUCTURE OF PEPTAIBOLIN, A NEW PEPTAIBOL FROM SEPEDONIUM STRAINS

peptaibols in microbial culture extracts3~5). Here we report the isolation and structure elucidation of peptaibolin (1, Fig. 1) as an unusual representative of the peptaibol family of lipophilic antibiotics. 1 was disclosed in two fungal strains, Sepedonium sp. HKI-0117 and Sepedonium ampullosporum HKI-0053 coproducing the neuroleptic peptaibol-type antibiotic ampullosporin5). In contrast to the known peptaibols6), the compound 1 contains only five peptide bonds. However, it displays all of the structural features of the

Discovery of new homologous pamamycins by mass spectrometry and post mortem inhibitory action on autolysis of chicken embryo chorioallantoic membrane blood vessels.

protonophoric agents10). The structural diversity of most of the published pamamycins has been ascribed to the substitution of protons or methyl groups at both parts of the macrodiolide ring by ethyl groups (see c. f. R1, R2, R3, R4 and R5 in Fig. 1)1,2,11). However, variations of the length of the nitrogen-containing side chain at the left side of the pamamycin skeleton (see c. f. R6 in Fig 1) have been reported for pamamycins-621 and -6354,5) harbouring the same ring structure as was shown for pamamycin-607 (R1=R2=R3=R4=R5=CH3)3). The homologous mixtures of pamamycins are difficult to separate owing to their high degree of chemical similarity. Structural assignment of the known individual components has employed chemical derivatizations4,10) in addition to spectroscopic methods. In the course of screening for embryotoxic compounds, an extract of Streptomyces sp. HKI-0118 was found to prevent post mortem the autolysis of the chorioallantoic membrane blood vessel tissues of 15-day-old embryonated chicken eggs. This effect was also observed in presence of the above extract when the mortalization of the embryo was induced by ergotamine tartrate. Here we report the occurence of new pamamycins with molecular weights of 663, 677, 691 and 705 Da in extracts of Streptomyces sp. HKI-0118 as constitutive parts of a mixture of homologous pamamycins containing also pamamycins-607, -621, -635 and -649. Due to the possibility of daughter-ion generation from the single [M+H]+ ions of a mixture, triple-quadrupole mass spectrometry (CID-MS/MS) appeared as a promising tool for the analysis of the new pamamycin complex.

Isolation and structure elucidation of new salfredin-type metabolites fromCrucibulum laeve DSM 1653 and DSM 8519

New salfredin‐type chromene and benzofurane metabolites (4—7) were isolated from submerged cultures of the fungal strains Crucibulum laeve DSM 1653 and C. laeve DSM 8519. The structures were elucidated on the basis of UV‐VIS spectroscopic, mass spectrometric and NMR spectroscopic evidence. The new metabolites are discussed as intermediates and shunt metabolites of the fungal aromatic pathway leading to A‐, B‐ and C‐type salfredins.

14-Hydroxy-12-oxo-10E,13E,15E-octadecatrienoic acid, a new fatty acid from a Vietnamese mushroom, Cantharellus friesiiQuel.

The new 14‐hydroxy‐12‐oxo‐10E,13E,15E‐octadecatrienoic acid (1) was isolated from the fruit bodies of a Vietnamese edible mushroom, Cantharellus friesii Quel. Purification was done by liquid chromatography and gel‐permeation chromatography. The structure was settled by mass spectrometric and NMR investigations.