In small series, third-party fecal microbiota transplantation (FMT) has been successful in decolonizing the gut from clinically relevant antibiotic resistance genes (ARGs). Less is known about the short- and long-term effects of FMT on larger panels of ARGs. We analyzed 226 pre- and post-treatment stool samples from a randomized placebo-controlled trial of FMT in 100 patients undergoing allogeneic hematopoietic cell transplantation or receiving anti-leukemia induction chemotherapy for 47 ARGs. These patients have heavy antibiotic exposure and a high incidence of colonization with multidrug-resistant organisms. Samples from each patient spanned a period of up to 9 months, allowing us to describe both short- and long-term effects of FMT on ARGs, while the randomized design allowed us to distinguish between spontaneous changes vs. FMT effect. We find an overall bimodal pattern. In the first phase (days to weeks after FMT), low-level transfer of ARGs largely associated with commensal healthy donor microbiota occurs. This phase is followed by long-term resistance to new ARGs as stable communities with colonization resistance are formed after FMT. The clinical implications of these findings are likely context-dependent and require further research. In the setting of cancer and intensive therapy, long-term ARG decolonization could translate into fewer downstream infections.

Previous research on antibiotic resistance genes and microorganisms centered on those in urban sewage treatment plants, breeding farms, hospitals and others with serious antibiotic pollution. However, at present, there are evident proofs that antibiotic resistance genes (ARGs) indeed exist in a primitive environment hardly without any human\'s footprints. Accordingly, an original karst mountain swamp ecosystem in Niangniang Mountain, Guizhou, China, including herbaceous swamp, shrub swamp, sphagnum bog and forest swamp, was selected to analyze the physical and chemical parameters of sediments. Moreover, microbial compositions, functions, as well as their connections with ARGs were assayed and analyzed using metagenomic technology. The results showed that there was no significant difference in the dominant microorganisms and ARGs in the four marshes, in which the dominant bacteria phyla were Proteobacteria (37.82 %), Acidobacteriota (22.17 %) and Actinobacteriota (20.64 %); the dominant archaea Euryarchaeota. (1.00 %); and the dominant eukaryotes Ascomycota (0.07 %), with metabolism as their major functions. Based on the ARDB database, the number of ARGs annotated reached 209 including 30 subtypes, and the dominant ARGs were all Bacitracin resistance genes (bacA, 84.77 %). In terms of the diversity of microorganisms and ARGs, the herbaceous swamp ranked the top, and the shrub swamp were at the bottom. Correlation analysis between microorganisms and resistance genes showed that, apart from aac2ic, macB, smeE, tetQ, and tetL, other ARGs were positively correlated with microorganisms. Among them, baca coexisted with microorganisms. Pearson correlation analysis results showed that contrary to ARGs, microorganisms were more affected by environmental factors.

Wastewater is considered the most serious source of the spread of antibiotic resistance in the environment. This work, therefore, focuses on the fate and spread of antibiotic resistance genes (ARGs) in wastewater and the monitoring of multidrug-resistant strains. ARGs were monitored in the nitrification and sedimentation tanks of the wastewater treatment plant (WWTP) and in the dam into which this WWTP flows, at various times. The highest relative abundance was found for the blaTEM > tetW > blaNDM-1 > vanA resistance genes, respectively. An increased concentration of tetracycline (up to 96.00 ng/L) and ampicillin (up to 19.00 ng/L) was found in water samples compared to other antibiotics detected. The increased incidence of seven ARGs and four antibiotics was observed in the November and December sampling times. Isolated ampicillin-resistant strains showed a high degree of resistance to ampicillin (61.2% of the total isolates had a minimum inhibitory concentration (MIC) ≥ 20 mg/mL). In 87.8% of isolates, out of the total number, the occurrence of two or more ARGs was confirmed. These multidrug-resistant strains were most often identified as Aeromonas sp. This strain could represent a significant role in the spread of multidrug resistance through wastewater in the environment.

Antibiotic resistance genes (ARGs) are emerging contaminants that pose a health risk to humans worldwide. Little information on ARGs in bee honey is available. This study profiles ARGs in bee honey samples produced in China, the biggest producer in the world. Of 317 known ARGs encoding resistance to 8 classes of antibiotics, 212 were found in collected honey samples by a real-time quantitative polymerase chain reaction approach. Occurrence frequencies of genes providing resistance to FCA (fluoroquinolone, quinolone, florfenicol, chloramphenicol, and amphenicol) and aminoglycosides were 21.0% and 18.5%, respectively. Frequencies of genes encoding efflux pumps were 42.5% and those of destructase genes 36.6%, indicating that these two mechanisms were predominant for resistance. Nine plasmid-mediated quinolone resistance genes were detected. Of the nine transposase genes known to be involved in antibiotic resistance, eight were found in the samples examined, with tnpA-4, tnpA-5, and tnpA-6 being more abundant. The abundance of the transposase genes was associated with genes conferring resistance to tetracyclines (r = 0.648, p < 0.01), macrolide-lincosamide-streptogramin B (r = 0.642, p < 0.01), FCA (r = 0.517, p < 0.01), and aminoglycosides (r = 0.401, 0.01 < p < 0.05). This is the first study on the abundance and diversity of ARGs in Chinese bee honey products. These findings suggest that bee honey may be a significant source of ARGs that might pose threat to public health. Further research is required to collect more samples in diverse geographic regions in China to make a more comprehensive judgment of ARG in bee honey.

Prophylactic usage and high persistent nature of several antibiotics have put selective pressure on the native microbial population that led to the emergence, propagation, and persistence of antibiotic resistance in nature. The surveillance of antibiotic resistome pattern and identification of points of intervention throughout the different environmental habitats will help to break the flow of antibiotic resistance from environmental bacteria to human pathogens. The present study compares the occurrence, diversity, and abundance of ARGs in industrial sludge, wetland sludge, and sediment sample contaminated with pharmaceutical discharge. Metagenomes were mined for the presence of ARGs against the ResFinder 3.2 database using BLASTn program. Pharmaceutical sample (2.52%) showed high degree of ARG abundance and richness as compared with ETP sludge (2.28%) and wetland sludge samples (1.29%). The modern resistome pattern represented by critically important resistance genes against tetracycline (tetA, tetC, tetW, tetT, and tetS/M) and quinolone (qnrS, qnrVC, and qnrD) was identified in pharmaceutical sediment sample. However, effluent treatment plant (ETP) sludge sample showed abundance of multidrug efflux pumps indicating the presence of primitive resistome profile. In conclusion, the indiscriminate distribution pattern of antibiotic resistance genes in three selected environmental sites suggests enrichment and distribution of environmental niche-driven resistance. The study also suggests effluent discharge site from pharmaceutical industries and ETPs as pivotal points of intervention for the mitigation of antibiotic resistance.