more information
Search within Results:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author (up) Brooks, J.P.; Adeli, A.; McLaughlin, M.R. file  url
openurl 
  Title Microbial ecology, bacterial pathogens, and antibiotic resistant genes in swine manure wastewater as influenced by three swine management systems Type Journal Article
  Year 2014 Publication Water Research Abbreviated Journal Water Res  
  Volume 57 Issue Pages 96-103  
  Keywords Animal Husbandry/*methods; Animals; Anti-Bacterial Agents/pharmacology; Bacteria/drug effects/*genetics/*isolation & purification; Bacterial Proteins/genetics/metabolism; Drug Resistance, Bacterial/*genetics; Manure/*microbiology; Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/isolation & purification; *Microbiota; RNA, Ribosomal, 16S/genetics/metabolism; Real-Time Polymerase Chain Reaction; Southeastern United States; Sus scrofa; Waste Water/*microbiology; Antibiotic resistance; Campylobacter; Confined animal feeding operation (CAFO); Lagoon wastewater; Salmonella; Swine; Microbiome  
  Abstract The environmental influence of farm management in concentrated animal feeding operations (CAFO) can yield vast changes to the microbial biota and ecological structure of both the pig and waste manure lagoon wastewater. While some of these changes may not be negative, it is possible that CAFOs can enrich antibiotic resistant bacteria or pathogens based on farm type, thereby influencing the impact imparted by the land application of its respective wastewater. The purpose of this study was to measure the microbial constituents of swine-sow, -nursery, and -finisher farm manure lagoon wastewater and determine the changes induced by farm management. A total of 37 farms were visited in the Mid-South USA and analyzed for the genes 16S rRNA, spaQ (Salmonella spp.), Camp-16S (Campylobacter spp.), tetA, tetB, ermF, ermA, mecA, and intI using quantitative PCR. Additionally, 16S rRNA sequence libraries were created. Overall, it appeared that finisher farms were significantly different from nursery and sow farms in nearly all genes measured and in 16S rRNA clone libraries. Nearly all antibiotic resistance genes were detected in all farms. Interestingly, the mecA resistance gene (e.g. methicillin resistant Staphylococcus aureus) was below detection limits on most farms, and decreased as the pigs aged. Finisher farms generally had fewer antibiotic resistance genes, which corroborated previous phenotypic data; additionally, finisher farms produced a less diverse 16S rRNA sequence library. Comparisons of Camp-16S and spaQ GU (genomic unit) values to previous culture data demonstrated ratios from 10 to 10,000:1 depending on farm type, indicating viable but not cultivatable bacteria were dominant. The current study indicated that swine farm management schemes positively and negatively affect microbial and antibiotic resistant populations in CAFO wastewater which has future “downstream” implications from both an environmental and public health perspective.  
  Call Number Serial 1943  
Permanent link to this record
 

 
Author (up) Chen, B.; Liang, X.; Nie, X.; Huang, X.; Zou, S.; Li, X. file  url
openurl 
  Title The role of class I integrons in the dissemination of sulfonamide resistance genes in the Pearl River and Pearl River Estuary, South China Type Journal Article
  Year 2015 Publication Journal of Hazardous Materials Abbreviated Journal J Hazard Mater  
  Volume 282 Issue Pages 61-67  
  Keywords Anti-Bacterial Agents/*analysis; Bacterial Proteins/genetics; China; DNA, Bacterial/analysis; Drug Resistance, Microbial/*genetics; Estuaries; *Genes, Bacterial; Geologic Sediments/analysis; *Integrons; RNA, Ribosomal, 16S/analysis; Rivers; Sulfonamides/*analysis; Water Pollutants/*analysis; Antibiotic resistance genes (ARG); Class 1 intergron, Pearl River Estuary (PRE); South China; Sulfonamide resistance genes (sul1, and sul2)  
  Abstract Antibiotic resistance genes (ARGs), as a newly emerging contaminant, are unique because they are disseminated through horizontal gene transfer in the environment. In the present study, a class 1 integron gene (int1) and various ARGs (sul1, sul2, sul3, qnrS, and ermB) were measured in water and sediment samples from the Pearl River (PR) to the Pearl River Estuary (PRE), where there is a distinct gradient in anthropogenic impact. The int1, sul1, and sul2 genes were detected in all samples, and their concentrations exhibited a clear trend of decline consistent with anthropogenic impact. Both the int1 and sul genes had dynamically migrated between water and sediments. The relative abundance of the int1 gene normalized to the 16S rRNA gene correlated significantly with the total concentrations of antibiotics in water and sediments. Good correlations were also observed between the abundance of int1 and each type of sul gene in the samples. However, the sul1 gene showed a much stronger relationship with int1 in different seasons, probably due to the presence of sul1 in the conserved region of class 1 integron. Our results strongly support that integrons play an important role in the dissemination of ARGs in human-impacted aquatic environments.  
  Call Number Serial 1217  
Permanent link to this record
 

 
Author (up) He, Y.; He, X. file  url
openurl 
  Title Molecular Design and Genetic Optimization of Antimicrobial Peptides Containing Unnatural Amino Acids against Antibiotic-Resistant Bacterial Infections Type Journal Article
  Year 2016 Publication Biopolymers Abbreviated Journal Biopolymers  
  Volume 106 Issue 5 Pages 746-756  
  Keywords antibiotic resistance; antimicrobial peptide; bacterial infection; rational molecular design; unnatural amino acid  
  Abstract Antimicrobial peptides (AMPs) have been the focus of intense research towards the finding of a viable alternative to current small-molecule antibiotics, owing to their commonly observed and naturally occurring resistance against pathogens. However, natural peptides have many problems such as low bioavailability and high allergenicity that largely limit the clinical applications of AMPs. In the present study, an integrative protocol that combined chemoinformatics modeling, molecular dynamics simulations, and in vitro susceptibility test was described to design AMPs containing unnatural amino acids (AMP-UAAs). To fulfill this, a large panel of synthetic AMPs with determined activity was collected and used to perform quantitative structure-activity relationship (QSAR) modeling. The obtained QSAR predictors were then employed to direct genetic algorithm (GA)-based optimization of AMP-UAA population, to which a number of commercially available, structurally diverse unnatural amino acids were introduced during the optimization process. Subsequently, several designed AMP-UAAs were confirmed to have high antibacterial potency against two antibiotic-resistant strains, i.e. multidrug-resistant Pseudomonas aeruginosa (MDRPA) and methicillin-resistant Staphylococcus aureus (MRSA), with minimum inhibitory concentration (MIC) < 10 mug/ml. Structural dynamics characterizations revealed that the most potent AMP-UAA peptide is an amphipathic helix that can spontaneously embed into an artificial lipid bilayer and exhibits a strong destructuring tendency associated with the embedding process. This article is protected by copyright. All rights reserved.  
  Call Number Serial 1270  
Permanent link to this record
 

 
Author (up) Lin, H.; Sun, W.; Zhang, Z.; Chapman, S.J.; Freitag, T.E.; Fu, J.; Zhang, X.; Ma, J. file  url
openurl 
  Title Effects of manure and mineral fertilization strategies on soil antibiotic resistance gene levels and microbial community in a paddy-upland rotation system Type Journal Article
  Year 2016 Publication Environmental Pollution (Barking, Essex : 1987) Abbreviated Journal Environ Pollut  
  Volume 211 Issue Pages 332-337  
  Keywords Antibiotic resistance genes; Fertilization; Manure; Paddy-upland rotation; Soil microbial community  
  Abstract This work investigated the responses of antibiotic resistance genes (ARGs) and the soil microbial community in a paddy-upland rotation system to mineral fertilizer (NPK) and different application dosages of manure combined with NPK. The occurrence of five tetracycline ARGs (tetA, tetB, tetC, tetG and tetW), two sulfonamide ARGs (sul1 and sul2) and one genetic element (IntI1) was quantified. NPK application showed only slight or no impact on soil ARGs abundances compared with the control without fertilizer. Soil ARGs abundances could be increased by manure-NPK application but was related to manure dosage (2250-9000 kg ha(-1)). Principal component analysis (PCA) showed that the soil ARG profile of the treatment with 9000 kg ha(-1) manure separated clearly from the other treatments; the ARGs that contributed most to the discrimination of this treatment were tetA, tetG, tetW, sul1, sul2 and IntI1. Community level physiological profile (CLPP) analysis showed that increasing manure dosage from 4500 kg ha(-1) to 9000 kg ha(-1) induced a sharp increase in almost all of the detected ARGs but would not change the microbial community at large. However, 9000 kg ha(-1) manure application produced a decline in soil microbial activity. Determination of antibiotics and heavy metals in soils suggested that the observed bloom of soil ARGs might associate closely with the accumulation of copper and zinc in soil.  
  Call Number Serial 1204  
Permanent link to this record
 

 
Author (up) Lin, H.; Sun, W.; Zhang, Z.; Chapman, S.J.; Freitag, T.E.; Fu, J.; Zhang, X.; Ma, J. file  url
openurl 
  Title Effects of manure and mineral fertilization strategies on soil antibiotic resistance gene levels and microbial community in a paddy-upland rotation system Type Journal Article
  Year 2016 Publication Environmental Pollution (Barking, Essex : 1987) Abbreviated Journal Environ Pollut  
  Volume 211 Issue Pages 332-337  
  Keywords Agriculture/*methods; Anti-Bacterial Agents/analysis; Drug Resistance, Microbial/*genetics; Fertilizers/analysis; Manure/analysis; Metals, Heavy/analysis; Minerals/*chemistry; Oryza; Rotation; Soil/*chemistry; *Soil Microbiology; Antibiotic resistance genes; Fertilization; Manure; Paddy-upland rotation; Soil microbial community  
  Abstract This work investigated the responses of antibiotic resistance genes (ARGs) and the soil microbial community in a paddy-upland rotation system to mineral fertilizer (NPK) and different application dosages of manure combined with NPK. The occurrence of five tetracycline ARGs (tetA, tetB, tetC, tetG and tetW), two sulfonamide ARGs (sul1 and sul2) and one genetic element (IntI1) was quantified. NPK application showed only slight or no impact on soil ARGs abundances compared with the control without fertilizer. Soil ARGs abundances could be increased by manure-NPK application but was related to manure dosage (2250-9000 kg ha(-1)). Principal component analysis (PCA) showed that the soil ARG profile of the treatment with 9000 kg ha(-1) manure separated clearly from the other treatments; the ARGs that contributed most to the discrimination of this treatment were tetA, tetG, tetW, sul1, sul2 and IntI1. Community level physiological profile (CLPP) analysis showed that increasing manure dosage from 4500 kg ha(-1) to 9000 kg ha(-1) induced a sharp increase in almost all of the detected ARGs but would not change the microbial community at large. However, 9000 kg ha(-1) manure application produced a decline in soil microbial activity. Determination of antibiotics and heavy metals in soils suggested that the observed bloom of soil ARGs might associate closely with the accumulation of copper and zinc in soil.  
  Call Number Serial 1680  
Permanent link to this record
 

 
Author (up) Luby, E.M.; Moorman, T.B.; Soupir, M.L. file  url
openurl 
  Title Fate and transport of tylosin-resistant bacteria and macrolide resistance genes in artificially drained agricultural fields receiving swine manure Type Journal Article
  Year 2016 Publication The Science of the Total Environment Abbreviated Journal Sci Total Environ  
  Volume 550 Issue Pages 1126-1133  
  Keywords *Agriculture; Animals; Drug Resistance, Bacterial/*genetics; *Environmental Monitoring; Macrolides/*analysis; Manure; *Soil Microbiology; Swine; Tylosin/analysis; Antibiotic resistance; Enterococcus; Manure; Soil; Swine; Tile drainage; erm genes  
  Abstract Application of manure from swine treated with antibiotics introduces antibiotics and antibiotic resistance genes to soil with the potential for further movement in drainage water, which may contribute to the increase in antibiotic resistance in non-agricultural settings. We compared losses of antibiotic-resistant Enterococcus and macrolide-resistance (erm and msrA) genes in water draining from plots with or without swine manure application under chisel plow and no till conditions. Concentrations of ermB, ermC and ermF were all >10(9)copies g(-1) in manure from tylosin-treated swine, and application of this manure resulted in short-term increases in the abundance of these genes in soil. Abundances of ermB, ermC and ermF in manured soil returned to levels identified in non-manured control plots by the spring following manure application. Tillage practices yielded no significant differences (p>0.10) in enterococci or erm gene concentrations in drainage water and were therefore combined for further analysis. While enterococci and tylosin-resistant enterococci concentrations in drainage water showed no effects of manure application, ermB and ermF concentrations in drainage water from manured plots were significantly higher (p<0.01) than concentrations coming from non-manured plots. ErmB and ermF were detected in 78% and 44%, respectively, of water samples draining from plots receiving manure. Although ermC had the highest concentrations of the three genes in drainage water, there was no effect of manure application on ermC abundance. MsrA was not detected in manure, soil or water. This study is the first to report significant increases in abundance of resistance genes in waters draining from agricultural land due to manure application.  
  Call Number Serial 1804  
Permanent link to this record
 

 
Author (up) Peng, S.; Wang, Y.; Zhou, B.; Lin, X. file  url
openurl 
  Title Long-term application of fresh and composted manure increase tetracycline resistance in the arable soil of eastern China Type Journal Article
  Year 2015 Publication The Science of the Total Environment Abbreviated Journal Sci Total Environ  
  Volume 506-507 Issue Pages 279-286  
  Keywords Agriculture/*methods; China; Fertilizers/*analysis; Manure/*analysis/microbiology; Soil/chemistry; *Soil Microbiology; Tetracycline Resistance/*genetics; Antibiotic resistance genes; Composting; Pollutant; Real-time PCR; Swine manure  
  Abstract The aim of this study was to compare the occurrence, abundance, and diversity of tetracycline resistance genes (tet) in agricultural soils after 6 years' application of fresh or composted swine manure. Soil samples were collected from fresh or composted manure-treated farmland at three depths (0-5 cm, 5-10 cm, and 10-20 cm). Nine classes of tet genes [tetW, tetB(P), tetO, tetS, tetC, tetG, tetZ, tetL, and tetX] were detected; tetG, tetZ, tetL, and tetB(P) were predominant in the manure-treated soil. The abundances of tetB(P), tetW, tetC, and tetO were reduced, while tetG and tetL were increased by fertilizing with composted versus fresh manure; thus, the total abundance of tet genes was not significantly reduced by compost manuring. tetG was the most abundant gene in manure-treated soil; the predominant tetG genotypes shared high homology with pathogenic bacteria. The tetG isolates were more diverse in soils treated with fresh versus composted manure, although the residual tet genes in composted manure remain a pollutant and produce a different influence on the tet gene resistome in field soil.  
  Call Number Serial 1201  
Permanent link to this record
 

 
Author (up) Sengeløv, G. file  url
openurl 
  Title Bacterial antibiotic resistance levels in Danish farmland as a result of treatment with pig manure slurry Type Journal Article
  Year 2003 Publication Environment International Abbreviated Journal Environment International  
  Volume 28 Issue 7 Pages 587-595  
  Keywords Antibiotic resistance; Soil; Farmland; Pig manure slurry; Tetracycline; Streptomycin; Macrolide  
  Abstract Resistance to tetracycline, macrolides and streptomycin was measured for a period of 8 months in soil bacteria obtained from farmland treated with pig manure slurry. This was done by spread plating bacteria on selective media (Luria Bertani (LB) medium supplemented with antibiotics). To account for seasonal variations in numbers of soil bacteria, ratios of resistant bacteria divided by total count on nonselective plates were calculated. Soil samples were collected from four different farms and from a control soil on a fifth farm. The control soil was not amended with animal manure. The occurrence of tetracycline-resistant bacteria was elevated after spread of pig manure slurry but declined throughout the sampling period to a level corresponding to the control soil. Higher load of pig manure slurry yielded higher occurrence of tetracycline resistance after spreading; however, the tetracycline resistance declined to normal occurrence defined by the tetracycline resistance occurrence in the control soil. Concentrations of tetracycline in soil and in pig manure slurry were measured using HPLC. No tetracycline exceeding the detection limit was found in soil samples. Manure slurry concentrations of tetracycline for three of the farms were 42, 81 and 698 &#956;g/l, respectively. For streptomycin and macrolides, only minor variations in resistance levels were detected. Results obtained in this study thus indicate that tetracycline resistance levels in soil are temporarily influenced by the addition of pig manure slurry. The results indicate also that increased amount of pig manure slurry amendment may result in increased levels of tetracycline resistance in the soil.  
  Call Number Serial 1956  
Permanent link to this record
 

 
Author (up) Zhou, X.; Qiao, M.; Wang, F.-H.; Zhu, Y.-G. file  url
openurl 
  Title Use of commercial organic fertilizer increases the abundance of antibiotic resistance genes and antibiotics in soil Type Journal Article
  Year 2017 Publication Environmental Science and Pollution Research International Abbreviated Journal Environ Sci Pollut Res Int  
  Volume 24 Issue 1 Pages 701-710  
  Keywords Animals; Anti-Bacterial Agents/*analysis; Chickens; Drug Resistance, Microbial/*genetics; *Fertilizers; *Genes, Bacterial; Integrons; *Manure; Soil Microbiology; Soil Pollutants/*analysis; Swine; *Antibiotic resistance genes; *Antibiotics; *Commercial organic fertilizers; *Repeated applications; *Soil  
  Abstract The application of manure-based commercial organic fertilizers (COFs) is becoming increasingly extensive because of the expanding market for organic food. The present study examined the effects of repeated applications of chicken or swine manure-based COFs on the fate of antibiotics and antibiotic resistance genes (ARGs) in soil by conducting a soil microcosm experiment. Application of COFs significantly increased antibiotics residues, as well as the relative abundance of ARGs and the integrase gene of class 1 integrons (intIota1) in soil. Two months after each application, antibiotics and ARGs dissipated in amended soils, but they still remained at an elevated level, compared with the control. And, the accumulation of antibiotics was found due to repeated COF applications. However, the relative abundance of ARGs in most COF-amended soils did not differ significantly between the first application and the repeated application. The results imply that 2 months are not sufficient for ARGs to approach background levels, and that animal manure must be treated more effectively prior to using it in agriculture ecosystems.  
  Call Number Serial 1803  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations: