Dynamics of the microbial community during growth of the house dust mite Dermatophagoides farinae in culture

Abstract

The variation in house dust mite microbial communities is important because various microorganisms modulate the production of allergens by their mite hosts and/or contaminate immunotherapeutic extracts. Temporal changes in mite microbiomes and the mite culture environment occurring at different stages of mite culture development are particularly understudied in this system. Here, we analyzed the dynamics of microbial communities during the culture growth of Dermatophagoides farinae. Changes in microbiomes were related to three key variables: the mite population density, microbial microcosm respiration and concentration of guanine (the mite nitrogenous waste metabolite). Mite populations exhibited the following phases: exponential growth, plateau and exponential decline. The intracellular bacterium Cardinium and the yeast Saccharomyces cerevisiae prevailed in the internal mite microbiomes, and the bacterium Lactobacillus fermentum was prevalent in the mite diet. The reduction in the mite population size during the late phases of culture development was related to the changes in their microbial profiles: the intracellular bacterium Cardinium was replaced by Staphylococcus, Oceanobacillus and Virgibacillus, and S. cerevisiae was replaced by the antagonistic fungi Aspergillus penicillioides and Candida. Increases in the guanine content were positively correlated with increases in the Staphylococcus and A. penicillioides profiles in the culture environment. Our results show that the mite microbiome exhibits strong, dynamic alterations in its profiles across different mite culture growth stages.

Microbiome variation during culture growth of the European house dust mite,Dermatophagoides pteronyssinus

“…decline after 84 days. Similarly, shortening of the culture time and absence of latency phase was observed for D. farinae previously [26]. During culturing, the mites produce guanine, a nitrogenous waste metabolite [18][19][20].…”

“…The dynamic of concentration and microcosm respiration showed similar patterns to D. farinae [26]. The nitrogenous waste dynamics is connected to the density of mite population, decreasing in the decline phase of D. pteronyssinus for D. farinae [26]. The microbial respiration in microcosms showed two small peaks after 30 and 70 days in the both species of mites [26].…”

“…During culturing, the mites produce guanine, a nitrogenous waste metabolite [18][19][20]. The dynamic of concentration and microcosm respiration showed similar patterns to D. farinae [26]. The nitrogenous waste dynamics is connected to the density of mite population, decreasing in the decline phase of D. pteronyssinus for D. farinae [26].…”

“…In this study, we hypothesized that the concentration of mite nitrogenous waste products and mite population density in uence microbial community structure inside mites and in the environmental culture of D. pteronyssinus. We previously observed differences in the microbiome composition of mites from young and old cultures [14] and the time changes of microbiome during colony culture growth of D. farinae [26]. Thus, we expected that the mites contaminate their environment by through their nitrogenous waste product guanine [18][19][20], which can serve as nutrient source for microorganisms.…”

Similarities and spatial variations of bacterial and fungal communities in field rice planthopper (Hemiptera: Delphacidae) populations

“…S10). Malassezia has also been identified in house dust mites (Klimov et al, 2019). The phylogenetic tree was not able to accurately assign every Alternaria and Aspergillus fungal ITS sequence to a species (Figs.…”