Data for: Heavy metal pollution impacts soil bacterial community structure and antimicrobial resistance at the Birmingham 35th Avenue Superfund Site

The data in this archive are the results of a study on the impact of heavy
metals (HMs) on the soil microbiota of an urban Superfund site in Alabama.
HMs are known to modify bacterial communities both in the laboratory and
in situ. Consequently, soils in HM-contaminated sites such as the U.S.
Environmental Protection Agency (EPA) Superfund sites are predicted to
have altered ecosystem functioning, with potential ramifications for the
health of organisms, including humans, that live nearby. Further, several
studies have shown that heavy metal-resistant (HMR) bacteria often also
display antimicrobial resistance (AMR), and therefore HM-contaminated
soils could potentially act as reservoirs that could disseminate AMR genes
into human-associated pathogenic bacteria. To explore this possibility,
topsoil samples were collected from six public locations in the zip code
35207 (the home of the North Birmingham 35th Avenue Superfund Site) and in
six public areas in the neighboring zip code, 35214. 35027 soils had
significantly elevated levels of the HMs As, Mn, Pb, and Zn, and
sequencing of the V4 region of the bacterial 16S rRNA gene revealed that
elevated HM concentrations correlated with reduced microbial diversity and
altered community structure. While there was no difference between zip
codes in the proportion of total culturable HMR bacteria, bacterial
isolates with HMR almost always also exhibited AMR. Metagenomes inferred
using PICRUSt2 also predicted significantly higher mean relative
frequencies in 35207 for several AMR genes related to both specific and
broad-spectrum AMR phenotypes. Together, these results support the
hypothesis that chronic HM pollution alters the soil bacterial community
structure in ecologically meaningful ways and may also select for bacteria
with increased potential to contribute to AMR in human disease.