Manganese and antibiotic biosynthesis. III. The site of manganese control of patulin production in Penicillium urticae

Abstract

Although manganese had been shown to be an essential requirement for patulin biosynthesis, its site of action was unknown. Four possibilities were considered. A manganese requirement for the second pathway enzyme, a decarboxylase, was discounted since mid and late pathway intermediates were not converted to patulin in manganese-deficient cultures. A major disruption in primary metabolism and hence secondary metabolism was discounted since eight primary metabolism enzymes showed no evidence of unusual changes in specific activity when normal and manganese-deficient cultures were compared. Inhibitor studies using actinomycin D and cycloheximide showed that there was no activation of preexisting enzyme proteins and that manganese did not influence translation. The inhibitor studies did show, however, that manganese exercised its effect on patulin biosynthesis by influencing the coordinate appearance of pathway enzymes though an effect at the level of transcription.

Manganese peroxidase gene transcription in Phanerochaete chrysosporium: activation by manganese

“…The results in Fig. 1 (43,53), this is, to our knowledge, the first instance in which Mn regulation of gene transcription has been examined on a molecular level, and further study will be required to clarify the mechanisms involved.…”

Biosynthesis and Toxicological Effects of Patulin

“…Inhibitor studies using actinomycin D and cycloheximide showed that manganese exercised its affect on patulin biosynthesis at the level of transcription and influenced the coordinated appearance of pathway enzymes [54]. This was confirmed by Northern Blot analysis [29].…”

Manganese inhibition of 3-acetyldeoxynivalenol biosynthesis in Fusarium graminearum R 2118

“…This is consistent with the necessity of using an Mn+Z-free production medium in the production of citric acid where an addition of a very small amount of Mn +2 is sufficient to significantly decrease the final yield of citric acid by A. niger (Clark et al 1966;Shu and Johnson 1948). In a culture of P. urtieae, Mn +2 at an initial medium concentration of 1.5 ~tM was sufficient to maintain a high level of I C D H activity (Scott et al 1986b). In F. culmorum, the mitochondrial I C D H activity is low during 3-ADN production, indicating an overall low TCA cycle activity (Miller and Blackwell 1986).…”