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The Science of the Total Environment May 2024Hospital wastewater treatment systems (HWTSs) are a significant source and reservoir of antibiotic resistance genes (ARGs) and a crucial hub for transmitting ARGs from...
Hospital wastewater treatment systems (HWTSs) are a significant source and reservoir of antibiotic resistance genes (ARGs) and a crucial hub for transmitting ARGs from clinical to natural environments. However, there is a lack of research on the antibiotic resistome of clinical wastewater in HWTSs. In this study, we used metagenomics to analyze the prevalence and abundance of ARGs in five typical HWTSs. A total of 17 antibiotics from six categories were detected in the five HWTSs; β-lactam antibiotics were found at the highest concentrations, with up to 4074.08 ng·L. We further found a total of 21 ARG types and 1106 subtypes of ARGs with the highest percentage of multi-drug resistance genes (evgS, msbA, arlS, and baeS). The most abundant last-resort ARGs were mcr, which were detected in 100 % of the samples. HWTSs effluent is a major pathway for the transmission of last-resort ARGs into urban wastewater networks. The removal of antibiotics, antibiotic-resistant bacteria, and ARGs from HWTSs was mainly achieved by tertiary treatment, i.e., chlorine disinfection, but antibiotics and ARGs were still present in the HWTSs effluent or even increased after treatment. Moreover, antibiotics and heavy metals (especially mercury) in hospital effluents can exert selective pressure for antibiotic resistance, even at low concentrations. Qualitative analyses based on metagenome-assembled genome analysis revealed that the putative hosts of the identified ARGs are widely distributed among Pseudomonas, Acidovorax, Flavobacterium, Polaromonas, and Arcobacter. Moreover, we further assessed the clinical availability of ARGs and found that multidrug ARGs had the highest clinical relevance values. This study provides new impulses for monitoring and removing antibiotics and ARGs in the hospital sewage treatment process.
Topics: Anti-Bacterial Agents; Wastewater; Genes, Bacterial; Hospitals; Water Purification
PubMed: 38508266
DOI: 10.1016/j.scitotenv.2024.171806 -
Food Chemistry: X Oct 2023In this study, the bacterial communities and flavor metabolites of 27 traditional naturally fermented sauerkraut samples collected from nine regions of Heilongjiang...
Exploring potential correlations between bacterial communities, organic acids, and volatile metabolites of traditional fermented sauerkraut collected from different regions of Heilongjiang Province in Northeast China.
In this study, the bacterial communities and flavor metabolites of 27 traditional naturally fermented sauerkraut samples collected from nine regions of Heilongjiang Province in Northeast China were investigated. The dominant genera were , , , , , , , , , and . A total of 148 volatile compounds were detected in seven categories; esters and acids were the most abundant volatiles. Additionally, the highest content (15.96 mg/g) of lactic acid was detected in YC1. Acetic acid, oleic acid, palmitic acid, elaidic acid, and dehydroacetic acid were the key differential volatile compounds, which may be related to the bacterial communities. Spearman's correlation analysis revealed that and were significantly positively correlated with flavor metabolites, suggesting that they may play a more significant role in flavor formation. The results of this study can help in the development of better quality of fermented vegetables.
PubMed: 37680758
DOI: 10.1016/j.fochx.2023.100840 -
Animals : An Open Access Journal From... Apr 2024Yaks are the main pillar of plateau animal husbandry and the material basis of local herdsmen's survival. The level of mineral elements in the body is closely related to...
Microbial Metagenomes and Host Transcriptomes Reveal the Dynamic Changes of Rumen Gene Expression, Microbial Colonization and Co-Regulation of Mineral Element Metabolism in Yaks from Birth to Adulthood.
Yaks are the main pillar of plateau animal husbandry and the material basis of local herdsmen's survival. The level of mineral elements in the body is closely related to the production performance of yaks. In this study, we performed a comprehensive analysis of rumen epithelial morphology, transcriptomics and metagenomics to explore the dynamics of rumen functions, microbial colonization and functional interactions in yaks from birth to adulthood. Bacteria, eukaryotes, archaea and viruses colonized the rumen of yaks from birth to adulthood, with bacteria being the majority. Bacteroidetes and Firmicutes were the dominant phyla in five developmental stages, and the abundance of genus and significantly decreased with age. Glycoside hydrolase (GH) genes were the most highly represented in five different developmental stages, followed by glycosyltransferases (GTs) and carbohydrate-binding modules (CBMs), where the proportion of genes coding for CBMs increased with age. Integrating host transcriptome and microbial metagenome revealed 30 gene modules related to age, muscle layer thickness, nipple length and width of yaks. Among these, the MEmagenta and MEturquoise were positively correlated with these phenotypic traits. Twenty-two host genes involved in transcriptional regulation related to metal ion binding (including potassium, sodium, calcium, zinc, iron) were positively correlated with a rumen bacterial cluster 1 composed of , , , , , etc. Therefore, these studies help us to understand the interaction between rumen host and microorganisms in yaks at different ages, and further provide a reliable theoretical basis for the development of feed and mineral element supplementation for yaks at different ages.
PubMed: 38731369
DOI: 10.3390/ani14091365 -
RSC Advances Feb 2024This study explores the removal of Cd(ii) from wastewater using a microbial electrolysis cell (MEC) to investigate the electrochemical performance and removal kinetics...
This study explores the removal of Cd(ii) from wastewater using a microbial electrolysis cell (MEC) to investigate the electrochemical performance and removal kinetics of an anodic polarity reversal biocathode and the mechanism of action of electrochemically active bacteria. Comparative electrochemical methods showed that using an anodic polarity reversal biocathode resulted in greater than 90% removal of different concentrations of Cd(ii) within three days, which may be related to the catalytic effect of anodic electrochemically active bacteria. However, due to the ability of bacteria to regulate, up to nearly 2 mg L of Cd(ii) ions will remain in solution. As shown by the linear fitting relationship between scanning speed and peak current, the removal process was dominated by adsorption control for 20-80 mg L Cd(ii) and diffusion control for 100 mg L Cd(ii). The analysis of raw sludge and sludge containing Cd(ii) showed that and were the primary cadmium-tolerant bacteria, and that the ability to remove Cd(ii) was the result of a synergistic collaboration between autotrophic and heterotrophic Gram-negative bacteria.
PubMed: 38348294
DOI: 10.1039/d3ra07771c -
Nature Communications Dec 2023Understanding voltage-gated sodium (Na) channels is significant since they generate action potential. Na channels consist of a pore domain (PD) and a voltage sensor...
Understanding voltage-gated sodium (Na) channels is significant since they generate action potential. Na channels consist of a pore domain (PD) and a voltage sensor domain (VSD). All resolved Na structures in different gating states have VSDs that tightly interact with PDs; however, it is unclear whether VSDs attach to PDs during gating under physiological conditions. Here, we reconstituted three different voltage-dependent NaAb, which is cloned from Arcobacter butzleri, into a lipid membrane and observed their structural dynamics by high-speed atomic force microscopy on a sub-second timescale in the steady state. Surprisingly, VSDs dissociated from PDs in the mutant in the resting state and further dimerized to form cross-links between channels. This dimerization would occur at a realistic channel density, offering a potential explanation for the facilitation of positive cooperativity of channel activity in the rising phase of the action potential.
Topics: Ion Channel Gating; Action Potentials; Membranes; Sodium
PubMed: 38114487
DOI: 10.1038/s41467-023-43347-3 -
Chemosphere Oct 2023Efficient nitrate removal from recirculating mariculture system (RMS) water is of significance since high concentration of nitrate would cause chronic health effects on...
Start-up of solid-phase denitrification process for treatment of nitrate-rich water in recirculating mariculture system: Carbon source selection and nitrate removal mechanism.
Efficient nitrate removal from recirculating mariculture system (RMS) water is of significance since high concentration of nitrate would cause chronic health effects on aquatic organisms and eutrophication. Solid-phase denitrification (SPD) is a safer and more sustainable approach than conventional heterotrophic denitrification by dosing liquid carbon sources. Thus, its application for treating nitrate-rich RMS water was investigated in this study. Poly 3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) was identified with the best nitrate removal among four kinds of carbon sources. PHBV-filled reactors started with mariculture, municipal and mixing sludges (at the ratio of 1:1) and fed with 200 mg L nitrate-rich RMS water all achieved over 81% nitrate removals with a HRT of 4 days. The dissolved organic carbon concentrations of the reactors were in the range of 3-9 mg L. Arcobacter, Halomonas, and Psedomonas were dominant genera responsible for nitrate removal in different reactors. Metagenomic analyses indicate that both denitrification and assimilatory nitrate reduction (ANR) are the main contributors to nitrate removals. Metagenomic results illustrated nirB/D cooperated with nasA may perform ANR pathway, which transformed nitrate to ammonia for biosynthesis. These results indicate that SPD could be a safer alternative for treating nitrate-rich RMS water, and provide new insights into nitrogen metabolism pathways in SPD process.
Topics: Nitrates; Denitrification; Carbon; Water; Bioreactors; Polyesters; Nitrogen
PubMed: 37479001
DOI: 10.1016/j.chemosphere.2023.139568 -
Le Infezioni in Medicina 2024(formerly ), is a newly recognized like emerging foodborne pathogen worldwide, usually causing gastrointestinal symptoms in young children. A 4-year-old boy was...
(formerly ), is a newly recognized like emerging foodborne pathogen worldwide, usually causing gastrointestinal symptoms in young children. A 4-year-old boy was admitted to the Department of Pediatrics, University Hospital of Split, Croatia, because of malnutrition, lost appetite and prolonged watery diarrhea. A comprehensive diagnostics, including biochemistry, haematology, allergology, microbiology and radiology, were performed. The only positive microbiology result was unexpected isolation of on selective media for , after 48 hours of incubation on 42°C, among microaerophilic atmosphere. Clinical course was favorable and after symptomatic therapy child was discharged in good clinical condition and normal peristalsis to home care, with the recommendation of taking high-protein preparations to improve nutritional status. In addition, we performed a literature review of clinical cases caused by infection. The first report of isolated from stool sample in a 4-year old boy in Croatia, along with other clinical reports in literature, highlights the importance of standardisation and improvement of microbiological analysis, especially implementation of new methods for the identification of emerging pathogens.
PubMed: 38827827
DOI: 10.53854/liim-3202-12 -
Viruses Mar 2024The concentration of viruses in sewage sludge is significantly higher (10-1000-fold) than that found in natural environments, posing a potential risk for human and...
The concentration of viruses in sewage sludge is significantly higher (10-1000-fold) than that found in natural environments, posing a potential risk for human and animal health. However, the composition of these viruses and their role in the transfer of pathogenic factors, as well as their role in the carbon, nitrogen, and phosphorus cycles remain poorly understood. In this study, we employed a shotgun metagenomic approach to investigate the pathogenic bacteria and viral composition and function in two wastewater treatment plants located on a campus. Our analysis revealed the presence of 1334 amplicon sequence variants (ASVs) across six sludge samples, with 242 ASVs (41.22% of total reads) identified as pathogenic bacteria. was found to be the most dominant pathogen accounting for 6.79% of total reads. The virome analysis identified 613 viral genera with being the most abundant genus at 41.85%. Approximately 0.66% of these viruses were associated with human and animal diseases. More than 60% of the virome consisted of lytic phages. Host prediction analysis revealed that the phages primarily infected (37.11%), (21.11%), and (7.11%). Furthermore, our investigation revealed an abundance of auxiliary metabolic genes (AMGs) involved in carbon, nitrogen, and phosphorus cycling within the virome. We also detected a total of 113 antibiotic resistance genes (ARGs), covering major classes of antibiotics across all samples analyzed. Additionally, our findings indicated the presence of virulence factors including the gene accounting for approximately 4.78%, along with toxin genes such as the gene representing approximately 73.48% of all detected virulence factors and toxin genes among all samples analyzed. This study expands our understanding regarding both pathogenic bacteria and viruses present within sewage sludge while providing valuable insights into their ecological functions.
Topics: Metagenomics; Wastewater; Bacteria; Sewage; Humans; Viruses; Metagenome; Bacteriophages; Virome; Water Purification; Animals
PubMed: 38675877
DOI: 10.3390/v16040535 -
Microorganisms Jan 2024The gill tissue of bivalve mollusks hosts rich symbiotic microbial communities that may contribute to host health. is an invasive Lessepsian oyster in the Eastern...
The gill tissue of bivalve mollusks hosts rich symbiotic microbial communities that may contribute to host health. is an invasive Lessepsian oyster in the Eastern Mediterranean Sea that has become highly abundant while constantly expanding its range northwestward. Using 16S rRNA gene amplicon sequencing, we examined how temperature affects oysters and their gill microbiota in a series of experiments: exposing them to the current annual seawater temperature range, to the colder temperature of the Western Mediterranean Sea, and to the elevated temperature as predicted under global warming scenarios. The bacterial genus dominated the communities of the , mainly upon exposure to winter-like (16 °C) temperatures. Exposure to the elevated seawater temperature resulted in a significant change in the bacterial communities, while the oysters maintained normal functioning, suggesting that the oyster may survive a seawater warming scenario. Exposure to 11 °C led to the health deterioration of the oysters, the emergence of opportunistic pathogens, such as , , , and , and a decline in the relative abundance of , suggesting that might not survive Western Mediterranean Sea winters. Both the host and its gill bacteria are thus greatly affected by temperature, which could consequently restrict the range of expansion of this and other invasive oysters.
PubMed: 38258023
DOI: 10.3390/microorganisms12010197 -
PloS One 2024Due to the dramatic reduction of sea cucumber Isostichopus badionotus populations in the Yucatan Peninsula by overfishing and poaching, aquaculture has been encouraged...
Due to the dramatic reduction of sea cucumber Isostichopus badionotus populations in the Yucatan Peninsula by overfishing and poaching, aquaculture has been encouraged as an alternative to commercial catching and restoring wild populations. However, the scarcity of broodstock, the emergence of a new disease in the auricularia larvae stage, and the development of skin ulceration syndrome (SUS) in the culture have limited aquaculture development. This study presents the changes in the intestine and skin microbiota observed in early and advanced stages of SUS disease in cultured juvenile I. badionotus obtained during an outbreak in experimental culture through 16S rRNA gene sequencing and histological evidence. Our results showed inflammation in the intestines of juveniles at both stages of SUS. However, more severe tissue damage and the presence of bacterial clusters were detected only in the advanced stages of SUS. Differences in the composition and structure of the intestinal and skin bacterial community from early and advanced stages of SUS were detected, with more evident changes in the intestinal microbial communities. These findings suggest that SUS was not induced by a single pathogenic bacterium. Nevertheless, a decrease in the abundance of Vibrio and an increase in Halarcobacter (syn. Arcobacter) was observed, suggesting that these two bacterial groups could be keystone genera involved in SUS disease.
Topics: Animals; Microbiota; Skin; Sea Cucumbers; Aquaculture; RNA, Ribosomal, 16S; Skin Ulcer; Disease Outbreaks; Gastrointestinal Microbiome
PubMed: 38820441
DOI: 10.1371/journal.pone.0303480