Incorporation of 14C-labelled amino acids into sporidesmolide I by Pithomyces chartarum (Sporidesmium bakeri)

1967

SUMMARYAs well as the known sporidesmolides I, I1 and 111, Pithomyces chartarum produces sporidesmolides or similar compounds which contain residues of erythro-isoleucine and a-hydroxyisocaproic acid. When erythro-L-isoleucine was added to the growth medium, synthesis of sporidesmolides I and I11 was inhibited and synthesis of isoleucine-containing sporidesmolides, mainly sporidesmolide 11, was promoted. Threo-L-isoleucine in the medium was poorly utilized, but its presence resulted in production of a very complex mixture of sporidesmolides containing a higher proportion of isoleucine residues than the control. Epimerization of erythro-D-isoleucine occurred in the medium. Neither epimer was well utilized, and this isomer had little effect on sporidesmolide production or composition ; it promoted some increase in the synthesis of isoleucine-containing sporidesmolides. Threo-Disoleucine had effects qualitatively similar to but less pronounced than those of erythro-L-isoleucine, probably because of extracellular epimerization. The use of epimeric pairs of amino acids as tools for investigating biochemical processes involving inversion of configuration at an amino acid a-carbon atom is suggested.

Section: Discussionsupporting

confidence: 71%

“…The whole of the sporidesmolide I molecule, except for the N-methyl group, may be derived from L-valine and L-leucine supplied in the medium (Butler et al 1962). Examples of antagonism, both between valine and isoleucine, and between leucine and isoleucine, have been reported (Meister, 1965).…”

Section: Discussionmentioning

confidence: 99%

Effects of Stereoisomeric Isoleucines on Sporidesmolide Biosynthesis by Pithomyces chartarum

1967

“…For isolation of depsipeptides, the organisms were grown on potato glucose agar slopes, and spores washed from these with sterile 0.05% (v/v) Lissapol N (Imperial Chemical Industries Ltd., Millbank, London) were used for inoculum. The medium for Pithomyces chartarum was potato + carrot extract (Done, Mortimer, Taylor & Russell, 1961), and that for IMI 101184 and P. maydicus IMI 46232 was the salts +glucose + asparagine medium of Ross (Butler, Russell & Clarke, 1962). For P. maydicus 1~198084 and for IMI 102682 this medium was enriched with yeast extract (0.1 yo, w/v; 'Difco' brand, Baird & Tatlock, Ltd., Chadwell Heath, Essex).…”

mentioning

confidence: 99%

Spore Surface Depsipeptides in Some Pithomyces Species

Bishop

Griffiths

et al. 1965

“…Culture media were sterilized by heating at 1 2 1 "C for 25 min in an autoclave. Sporulation medium contained: sodium acetate trihydrate, 2 g ; Bacto-tryptone, 2 g ; KCI, 0.25 g; MgS04.7H,0, 0.25 g; KH2P04, 0.5 g; FeS0,.7H20, 5 mg; Ca(N03),.4H20, 30 mg; trace-metal solution (Butler, Russell & Clarke, 1962), 5 ml; and distilled water to I 1. To determine the effect of carbon source and concentration on sporulation, the sodium acetate was altered in concentration or replaced by another carbon compound.…”

Section: Methodsmentioning

confidence: 99%

Production of Enniatins by Fusarium sambucinum: Selection of High-yield Conditions from Liquid Surface Cultures

Audhya

1974