21145409

not annotated - annotated - LINNAEUS only

Overexpression of the trichodiene synthase gene tri5 increases trichodermin production and antimicrobial activity in Trichoderma brevicompactum.

Trichoderma brevicompactum produces trichodermin, a simple trichothecene-type toxin that shares the first steps of the sesquiterpene biosynthetic pathway with other phytotoxic trichothecenes from Fusarium spp. Trichodiene synthase catalyses the conversion of farnesyl pyrophosphate to trichodiene and it is encoded by the tri5 gene that was cloned and analysed functionally by homologous overexpression in T. brevicompactum. tri5 expression was up-regulated in media with glucose, H(2)O(2) or glycerol. tri5 repression was observed in cultures supplemented with the antioxidants ferulic acid and tyrosol. Acetone extracts of tri5-overexpressing transformants displayed higher antifungal activity than those from the wild-type. Chromatographic and spectroscopic analyses revealed that tri5 overexpression led to an increased production of trichodermin and tyrosol. Agar diffusion assays with these two purified metabolites from the tri5-overexpressing transformant T. brevicompactum Tb41tri5 showed that only trichodermin had antifungal activity against Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida albicans, Candida glabrata, Candida tropicalis and Aspergillus fumigatus, in most cases such activity being higher than that observed for amphotericin B and hygromycin. Our results point to the significant role of tri5 in the production of trichodermin and in the antifungal activity of T. brevicompactum.



Ann file

T1	Species 117 143	Trichoderma brevicompactum

N1 Reference T1 Taxonomy:247546

T2 Species 147 173 Trichoderma brevicompactum

N2 Reference T2 Taxonomy:247546

T3 Species 343 355 Fusarium spp

N3 Reference T3 Taxonomy:29916

T4 Species 553 570 T. brevicompactum

N4 Reference T4 Taxonomy:247546

T5 Species 1111 1128 T. brevicompactum

N5 Reference T5 Taxonomy:247546

T6 Species 1200 1224 Saccharomyces cerevisiae

N6 Reference T6 Taxonomy:4932

T7 Species 1226 1249 Kluyveromyces marxianus

N7 Reference T7 Taxonomy:4911

T8 Species 1251 1267 Candida albicans

N8 Reference T8 Taxonomy:5476

T9 Species 1269 1285 Candida glabrata

N9 Reference T9 Taxonomy:5478

T10 Species 1287 1305 Candida tropicalis

N10 Reference T10 Taxonomy:5482

T11 Species 1310 1331 Aspergillus fumigatus

N11 Reference T11 Taxonomy:746128

T12 Species 1546 1563 T. brevicompactum

N12 Reference T12 Taxonomy:247546

#1 AnnotatorNotes T3 TODO check