Differences in bacterial composition between men's and women's restrooms and other common areas within a public building

Microbiota Profiling on Veterinary Faculty Restroom Surfaces and Source Tracking

In this study, we aimed to develop a comprehensive microbial source amplicon database tailored for source tracking in veterinary settings. We rigorously tested our locally curated source tracking database by selecting a frequently accessed environment by veterinary students and veterinarians. By exploring the composition of resident microbiota and identifying potential sources of contamination, including animals, the environment, and human beings, we aimed to provide valuable insights into the dynamics of microbial transmission within veterinary facilities. The 16S rDNA amplicon sequencing was used to determine the bacterial taxonomic profiles of restroom surfaces. Bacterial sources were identified by linking our metadata-enriched local database to the microbiota profiling analysis using high-quality sequences. Microbiota profiling shows the dominance of four phyla: Actinobacteria, Bacteroidetes, Proteobacteria, and Firmicutes. If the restroom cleaning process did not appear to impact microbiota composition, significant differences regarding bacterial distribution were observed between male and female users in different sampling campaigns. Combining 16S rDNA profiling to our specific sources labeling pipeline, we found aquatic and human sources were the primary environment keywords in our campaigns. The probable presence of known animal sources (bovids, insects, equids, suids…) associated with bacterial genera such as Chryseobacterium, Bergeyella, Fibrobacter, and Syntrophococcus was also involved in restroom surfaces, emphasizing the proximity between these restrooms and the exchange of bacteria between people involved in animals handling. To summarize, we have demonstrated that DNA sequence-based source tracking may be integrated with high-throughput bacterial community analysis to enrich microbial investigation of potential bacterial contamination sources, especially for little known or poorly identified taxa. However, more research is needed to determine the tool's utility in other applications.

The impact of early-life exposure to three agrochemicals on survival, behavior, and gut microbiota of stingless bees (Partamona helleri)

Over the last few decades, agrochemicals have been partially associated with a global reduction in bees' population. Toxicological assessment is therefore crucial for understanding the overall agrochemical risks to stingless bees. Therefore, the lethal and sublethal effects of agrochemicals commonly used in crops (copper sulfate, glyphosate, and spinosad) on the behavior and gut microbiota of the stingless bee, Partamona helleri, were assessed using chronic exposure during the larval stage. When used at the field-recommended rates, both copper sulfate (200 µg of active ingredient/bee; a.i µg bee^-1) and spinosad (8.16 a.i µg bee^-1) caused a decrease in bee survival, while glyphosate (148 a.i µg bee^-1) did not show any significant effects. No significant adverse effects on bee development were observed in any treatment with CuSO₄ or glyphosate, but spinosad (0.08 or 0.03 a.i µg bee ^-1) increased the number of deformed bees and reduced their body mass. Agrochemicals changed the behavior of bees and composition of the gut microbiota of adult bees, and metals such as copper accumulated in the bees' bodies. The response of bees to agrochemicals depends on the class or dose of the ingested compound. In vitro rearing of stingless bees' larvae is a useful tool to elucidate the sublethal effects of agrochemicals.

Impact of environmental factors and bacterial interactions on dust mite allergens in different indoor dust

Indoor dust is the main carrier of indoor pollutants, especially dust mite allergens and bacteria, they can trigger asthma, rhinitis, eczema and other allergic diseases. However, the interactions between dust mite allergens and bacterial communities in different types of indoor dust are not clear. The study focused on particulate and flocculent fibrous dust, explored the concentrations of Der p 1 (Dermatophagoides pteronyssinus) and Der f 1 (D. farinae) in 46 households in Changchun and their environmental influences, characterized the bacterial communities by high-throughput sequencing, and the interactions between Der p 1, Der f 1 and bacterial communities were explored. The results showed that Der p 1 and Der f 1 tended to accumulate more in flocculent fibrous dust, and Der p 1 predominated in the indoor dust samples. The floor height, years of housing occupancy and the living areas all affected the concentrations of dust mite allergens. In bacterial community, Proteobacteria, Firmicutes and Actinobacteria were leading phyla in the two types of dust. Kocuria, Blastococcus and Massilia were dominating genera in particulate dust and Acinetobacter, Lactobacillus, Corynebacterium_1 were dominating genera in flocculent fibrous dust. The overall diversity and species richness of bacteria in particulate dust were significantly higher than those in flocculent dust (p < 0.001). The living area was an important environmental factor affecting the bacterial community in flocculent fibrous dust (p < 0.01). The interaction between the relative abundance of Proteobacteria, Firmicutes and Actinobacteria and dust mite allergen concentrations significantly differed between the two dust types, indicating that bacteria could be used both as food and to establish symbiotic relationships with household dust mites (HDMs) hosts and provide nutrition.

Comparative effects of environmental factors on bacterial communities in two types of indoor dust: Potential risks to university students

University students are constantly exposed to potential bacterial pathogens and environmental pollutants in indoor environment because they spend most of their time indoors. University dormitory and printing shop are two typical indoor environments frequented by university students. However, little is known about the characteristics of bacterial community as well as the effect of indoor environmental factors on them. 16S rRNA gene sequencing was used to reveal the bacterial community in indoor dust, electronic devices were recorded during dust sampling, and polybrominated diphenyl ethers (PBDEs) were detected by gas chromatography mass spectrometry (GC-MS). Proteobacteria, Actinobacteria and Firmicutes were leading phyla, and Acinetobacter, Paracoccus and Kocuria were dominating genera. The predominant genera showed Acinetobacter > Paracoccus > unidentified Corynebacteriaceae in indoor dusts from university dormitories, whereas Paracoccus > unidentified Cyanobacteria > Acinetobacter in printing shops. The occurrence of Acinetobacter, Kocuria, Corynebacterium, Pseudomonas, and Bacillus suggested the health risks of potential pathogenic bacteria to university students. Significant differences of microbial composition and diversity were proved between university dormitories and printing shops. Chemoheterotrophy and aerobic chemoheterotrophy were dominant bacterial functions, and the seven primary bacterial functions displayed university dormitory > printing shop. BDE 138 and BDE 66 were main environmental parameters affecting the indoor dust bacterial community in university dormitory, while printer and BDE 47 played dominating role in shaping microorganism in printing shop. The complex biotic (potential bacterial pathogens) and abiotic factors (electronic equipment and chemical pollutants) in indoor dusts may pose potential health risks to university students.

The vaginal microbial communities of healthy expectant Brazilian mothers and its correlation with the newborn's gut colonization

The female lower genital tract harbors a complex microbial community essential for homeostasis and health. During pregnancy, the female body undergoes unique hormonal changes that contribute to weight gain as well as modulations in immune function that can affect microbiota composition. Several studies have described the vaginal microbiota of pregnant women from the USA, Europe and Mexico. Here we expand our knowledge about the vaginal microbial communities during the third trimester to healthy expectant Brazilian mothers. Vaginal samples were collected from patients delivering at the Hospital de Clínicas de Porto Alegre, Brazil. Microbial DNA was isolated from samples and the V4 region of the 16S rRNA gene was amplified and sequenced using the PGM Ion Torrent. Brazilian pregnant women presented three distinct types of microbial community at the time of labor. Two microbial communities, Cluster 1 and Cluster 3, presented an overall dominance of Lactobacillus while Cluster 2 tended to present higher diversity and richness, with the presence of Pseudomonas, Prevotella and other vaginosis related bacteria. About half of the Brazilian mothers sampled here had dominance of L. iners. The proportion of mothers without dominance of any Lactobacillus was higher in Brazil (22%) compared to UK (2.4%) and USA, where this community type was not detected. The vaginal microbiota showed significant correlation with the composition of the babies' gut microbiota (p-value = 0.002 with a R² of 15.8%). Mothers presenting different vaginal microbiota shared different microorganisms with their newborns, which would reflect on initial colonizers of the developing newborns' gut.