Acrebol, a novel toxic peptaibol produced by an Acremonium exuviarum indoor isolate

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • University of Helsinki
  • University of Szeged

Abstract

To identify a toxin and its producer isolated from woody material in a building where the occupants experienced serious ill health symptoms.

Hyphal extracts of an indoor fungus, identified as the cycloheximide-tolerant species Acremonium exuviarum, inhibited motility of boar spermatozoa (EC(50) 5 +/- 2 mu g of crude solids ml(-1)) and caused cytolysis of murine neuroblastoma cells (MNA) and feline fetal lung cells (FL). The responsible substances were purified and identified as two structurally similar, heat-stable, novel, toxic peptaibols, 1726 Da and 1740 Da, respectively, with amino acid sequences of Acetyl-Phe-Iva/Val-Gln-Aib-Ile-Thr-Leu-Aib-Pro-Aib-Gln-Pro-Aib-(X-X-X)-SerOH and Acetyl-Phe-Iva/Val-Gln-Aib-Ile-Thr-Leu-Val-Pro-Aib-Gln-Pro-Aib-(X-X-X)-SerOH. Purified acrebol inhibited motility of boar sperm, depleted ATP half-content in 1 day (EC(50) of 0.1 mu g ml(-1), 60 nmol l(-1)) depolarised the mitochondria after 2 days, but did not affect the cellular content in NADH. This indicates mitochondrial toxicity. Plate-grown biomass of A. exuviarum BMB4 contained 0.1-1% (w/w) of acrebol, depending on the culture medium.

Acrebol paralysed the energy generation of mammalian cells suggesting that mitochondria were its target of action.

Acremonium exuviarum, as an indoor fungus, is potentially hazardous to health because of the toxic peptaibols that it produces.

Details

Original languageEnglish
Pages (from-to)909-923
Number of pages15
JournalJournal of Applied Microbiology
Volume106
Issue number3
Publication statusPublished - Mar 2009
MoE publication typeA1 Journal article-refereed

    Research areas

  • acrebol, antimycin, mitochondrial toxicity, moldy building, myxothiazol, sperm toxic, BUILDING-MATERIALS, DAMAGED BUILDINGS, MAMMALIAN-CELLS, MOLD GROWTH, ION-CHANNEL, SP-NOV, STACHYBOTRYS, ENVIRONMENT, PEPTAIBIOTICS, ANTIBIOTICS

ID: 7090534