Unsaturated fatty acids are the active molecules of a glucan-synthase-inhibitory fraction isolated from entomophthoralean protoplasts

Abstract

A few entomophthoralean species are able to multiply in a protoplast form. The polysaccharide synthases which synthesize the cell wall are inactivated in this form. An inhibitor of one of the key enzymes of wall synthesis, glucan synthase, was isolated from entomophthoralean protoplasts, using silica column chromatography and HPLC. Thin-layer and gas chromatography revealed free fatty acids in the inhibitory fractions. These fatty acids, including long-chain unsaturated fatty acids, were shown to be responsible for the inhibition of glucan synthase. The fatty acids were generated during incubation of a protoplast homogenate for 36 h at 37 "C and were shown to be non-competitive and non-specif ic inhibitors of glucan synthase.

Molecular analysis of ∆6 desaturase and ∆6 elongase from Conidiobolus obscurus in the biosynthesis of eicosatetraenoic acid, a ω3 fatty acid with nutraceutical potentials

“…The protoplasts, unlike hyphal bodies, are not 56 recognized by the immune system of insects because of the lack of -1,3 glucan in the 57 cell walls (Tanada and Kaye 2003). It appears that VLCPUFAs can inhibit the synthesis 58 of -1,3 glucan in the protoplasts, allowing the fungus to evade the host immune system 59 and to eventually kill its host (Mackichan et al 1995). 60 in oceans, the nutraceutical industry is now under intense pressure to find alternative 68 sources for these fatty acids to meet the growing demand.…”

Klonierung und Expression einer extrazellulären Lipase von A. fumigatus

“…Abbauprozessen der Zellwand, welche im Wesentlichen aus Chitin besteht, beteiligt.So konntenMackichan et al (1995) zeigen, dass in Anwesenheit hoher Konzentrationen freier Fettsäuren die Chitinsynthase von A. fumigatus, das Schlüsselenzym der Chitinsynthese, gehemmt wird. Asif et al (2006) extrahierten eine extrazelluläre Lipase von der Sporenoberfläche des A. fumigatus (Accession-Nummer: Q4WE77) mit einem Molekulargewicht von 32 kDa.…”