Melinacidin-producing acrostalagmus luteoalbus, a major constituent of mixed mycobiota contaminating insulation material in an outdoor wall

Maria A. Andersson*, Johanna Salo, Raimo Mikkola, Tamás Marik, László Kredics, Jarek Kurnitski, Heidi Salonen

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

19 Downloads (Pure)

Abstract

Occupants may complain about indoor air quality in closed spaces where the officially approved standard methods for indoor air quality risk assessment fail to reveal the cause of the problem. This study describes a rare genus not previously detected in Finnish buildings, Acrostalagmus, and its species A. luteoalbus as the major constituents of the mixed microbiota in the wet cork liner from an outdoor wall. Representatives of the genus were also present in the settled dust in offices where occupants suffered from symptoms related to the indoor air. One strain, POB8, was identified as A. luteoalbus by ITS sequencing. The strain produced the immunosuppressive and cytotoxic melinacidins II, III, and IV, as evidenced by mass spectrometry analysis. In addition, the classical toxigenic species indicating water damage, mycoparasitic Trichoderma, Aspergillus section Versicolores, Aspergillus section Circumdati, Aspergillus section Nigri, and Chaetomium spp., were detected in the wet outdoor wall and settled dust from the problematic rooms. The offices exhibited no visible signs of microbial growth, and the airborne load of microbial conidia was too low to explain the reported symptoms. In conclusion, we suggest the possible migration of microbial bioactive metabolites from the wet outdoor wall into indoor spaces as a plausible explanation for the reported complaints.

Original languageEnglish
Article number843
Number of pages24
JournalPathogens
Volume10
Issue number7
DOIs
Publication statusPublished - Jul 2021
MoE publication typeA1 Journal article-refereed

Keywords

  • Acrostalagmus luteoalbus
  • Cork liner
  • Guttation droplets
  • Indoor dust
  • Melinacidin
  • Mixed mycobiota
  • Outdoor wall

Fingerprint

Dive into the research topics of 'Melinacidin-producing acrostalagmus luteoalbus, a major constituent of mixed mycobiota contaminating insulation material in an outdoor wall'. Together they form a unique fingerprint.

Cite this