The T-shirt microbiome is distinct between individuals and shaped by washing and fabric type.

Activity of the microbial population in clothing causes unpleasant odor and textile deterioration. However, little is known about how the textile microbial community is shaped. In this study, we developed a method for extracting DNA from small amounts of detergent-washed clothing, and applied it to both worn and unworn, washed and unwashed cotton and polyester samples of the axillary region of T-shirts from 10 male subjects. The combined application of 16S rRNA gene amplicon sequencing and quantitative PCR allowed us to estimate the absolute abundances of bacteria in the samples. We found that the T-shirt microbiome was highly individual, both in composition, diversity and microbial biomass. Fabric type was influential where Acinetobacter was more abundant in cotton. Intriguingly, unworn cotton T-shirts had a native microbiome dominated by Acinetobacter, whereas unworn polyester had no detectable bacterial microbiome. The native textile microbiome did not seem to have any effect on the microbial composition emerging from wearing the garment. Surprisingly, washing in mild detergent had only minor effects on the composition and biomass of the microbial community, and only few Amplicon Sequence Variants (ASV)s were found to decrease in abundance after washing. Individual variations between test subjects shaped the microbial community more than the type of fabric or wash with detergent. The individuality of T-shirt microbiomes and specificity of the washing procedure suggests that personalized laundry regimes could be applied to increase efficient removal of undesired bacteria.

Parasite communities of two three-spined stickleback populations in subarctic Norway--effects of a small spatial-scale host introduction.

Co-introduction and colonization of parasites with the introduction of new host species into aquatic habitats may depend on the host specificity and dispersal capabilities of the parasites. We compared the metazoan parasite community of an introduced three-spined stickleback (Gasterosteus aculeatus) population with that of the nearby source population in subarctic Norway. As expected from a small spatial scale (5 km), the parasite component communities in the two lakes were highly similar. All identifiable allogenic parasite taxa (Diphyllobothrium dendriticum, Diphyllobothrium ditremum, Diphyllobothrium spp., Schistocephalus solidus, Apatemon sp. and Diplostomum spp.) were also observed in both lakes while inter-lake differences were driven by autogenic parasite taxa (Eubothrium spp., Crepidostomum spp., Nematoda spp., Proteocephalus sp. and Gyrodactylus arcuatus). Contrary to expectation, the total number of parasite taxa was higher in the introduced stickleback population (12) compared to that found in the source population (9) with three parasite taxa (Eubothrium spp., Crepidostomum spp., Nematoda spp.) only occurring in the introduced population. These parasites were uncommon however and normally restricted to salmonids. Sticklebacks from both populations were heavily infected, particularly with eye-infecting metacercariae. Sequences from the DNA barcode region of cytochrome oxidase 1 indicated that these include Diplostomum lineage 6, a member of the Diplostomum baeri complex and a member of the Strigeinae. Despite high similarity between the two component communities, quantitative inter-lake differences were found at the infracommunity level. At this scale, parasite intensity was significantly higher in the source population for the two autogenic stickleback specialists: G. arcuatus and Proteocephalus sp., assumed to be the autogenic stickleback specialist Proteocephalus filicollis. Parasite infracommunities within each lake also resembled each other significantly more than infracommunities between lakes, primarily driven by the allogenic cestode D. ditremum, as well as G. arcuatus and Proteocephalus sp. Overall, quantitative dissimilarities between the two parasite communities were possibly explained by inter-lake differences in the density of sticklebacks and intermediate hosts.