2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
Microbiologists from Russia and the United States have published the results of a study of the microbiota of the Moscow metro. Analysis of bacteria inhabiting four metro stations - Rimskaya, Dostoevskaya, Sretensky Boulevard and Vystavochnaya - showed that the diversity of microorganisms correlates with the amount of passenger traffic, and the backbone of the Moscow metrobiota is made up of the same genera as in the New York subway. The work was published in the Computational and Structural Biotechnology Journal.
Public transport is one of the key points of contact for residents of megalopolises. In addition to people, there are quite a lot of microorganisms in the metro, buses and trams, and it is important to understand how their community works, for example, for health care. In 2015, for this purpose, the MetaSUB (Metagenomics and Metadesign of the Subways and Urban) project was launched, within which it is planned to create maps of the microbiomes of subways of different cities.
Natalia Klimenko from Knomics and her colleagues from ITMO University, Novosibirsk and Baltic Universities, the Institute of Gene Biology and the Kurchatov Institute, Atlas and a number of other organizations in Russia and the United States studied how the microbiota of the Moscow metro works. Four stations were selected for the pilot experiment: Rimskaya, Dostoevskaya, Vystavochnaya and Sretensky Boulevard. At each station, the team collected samples from five types of surfaces - from handrails near escalators, navigation stands, floor, benches and walls at shoulder level. The ribosomal DNA of the bacteria caught in the samples was sequenced and, by comparing it with databases, they found out exactly who it belonged to.
The most common were bacteria from the genera Dietzia, Brevundimonas, Pseudomonas, Arsenicicoccus, Stenotrophomonas - their DNA was found in most samples. These are bacteria common to soil, and Dietzia can also live on human skin. Comparison with previous similar research done in the New York subway showed that at least three of these bacterial genera are "popular" there as well. In general, the stations were mainly occupied by soil bacteria, bacteria typical for human skin, as well as pathogens and plant symbionts, presumably brought into the subway with the soil.
Distribution of the ten most common bacterial taxa by stations and types of surfaces
Public transport is considered one of the key places for the transmission of microbes from person to person, and therefore special attention has been paid to finding pathogenic bacteria. However, the authors failed to find anyone from the list of ten detectable bacterial pathogens (it included, for example, Helicobacter, Salmonella, Haemophilus influenzae, Legionella), although the limitations of the method and the small number of samples do not allow to completely exclude the presence of these and other pathogens.
The station Rimskaya turned out to be the richest station in terms of microbiota diversity. The authors of the work suggest that this may be due to the large passenger traffic at this station: according to the metro, it is several times more than at other checked stations: 36, 5 thousand people a day versus 18, 2 - 6, 5 thousand.
Comparison of the “population” of different surfaces showed that the greatest diversity of bacteria is on the floor of the stations. There were many bacteria that were unique for this study.
The list of organisms found by the authors is approximate - the method allows only approximately to determine the taxonomic affiliation of the inhabitants of the subway, and fungi and other eukaryotic microorganisms were not taken into account at all. Despite these limitations, this pilot study provided an opportunity to test the methodology and provide the first insight into the microbiota of the Moscow subway.
Recently, we talked about the ISS microbiome - despite its unique conditions, it turned out to be similar to that found in most earthly buildings that people regularly visit - fitness centers, offices, hospitals. The ISS is inhabited by approximately the same bacteria and fungi that are found on the skin of animals and humans under normal conditions.
