Detection and molecular characterization of filamentous actinobacteria and thermoactinomycetes present in water-damaged building materials.
In this study the dominant filamentous actinobacteria occurring in water-damaged building materials were detected by culture and characterized by automated ribotyping and 16S rRNA gene sequencing. Fifty-two samples were taken from 20 water-damaged houses in four different countries. A total of 122 bacterial isolates were analyzed. Actinobacteria or thermoactinomycetes were present in 48% of the samples. The dominant genus was Streptomyces (58% of isolates), followed by Thermoactinomyces (23%), Laceyella (14%), Nocardiopsis (3%), Pseudonocardia (1%) and Saccharomonospora (1%). The most frequently detected species was the thermophilic Thermoactinomyces vulgaris (14 samples/4 countries). The most common streptomycetes were closely related to the heterogeneous species Streptomyces microflavus (7/2) or Streptomyces griseus (6/2). Automated ribotyping was a rapid tool for reliable characterization of these isolates. The spores of thermoactinomycetes and toxic substances of Nocardiopsis species and S. griseus may constitute a risk for human health.


CONCLUSIONS
Harmful microbes in indoor environments are a cause of public concern. To develop rapid and simple-to-use molecular biological methods to detect the presence of harmful actinobacterial species in water-damaged buildings more information about their occurrence in those materials is needed, which this study provides.
Suihko
M-L
ML
VTT Technical Research Centre of Finland, Espoo, Finland.
Priha
O
O
Alakomi
H-L
HL
Thompson
P
P
Mälarstig
B
B
Stott
R
R
Richardson
M
M
D039903:Actinobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D003252:Construction Materials / Q000382:microbiology*; D055868:Floods; D006798:Housing; D006801:Humans; D008848:Micromonosporaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D021521:Ribotyping
D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S