scholarly journals Effect of commercially purified deoxynivalenol and zearalenone mycotoxins on microbial diversity of pig cecum contents

2021 ◽  
Vol 34 (2) ◽  
pp. 243-255
Author(s):  
Kondreddy Eswar Reddy ◽  
Minji Kim ◽  
Ki Hyun Kim ◽  
Sang Yun Ji ◽  
Youlchang Baek ◽  
...  

Objective: Deoxynivalenol (DON) and zearalenone (ZEN) are mycotoxins that frequently contaminate maize and grain cereals, imposing risks to the health of both humans and animals and leading to economic losses. The gut microbiome has been shown to help combat the effects of such toxins, with certain microorganisms reported to contribute significantly to the detoxification process.Methods: We examined the cecum contents of three different dietary groups of pigs (control, as well as diets contaminated with 8 mg DON/kg feed or 0.8 mg ZEN/kg feed). Bacterial 16S rRNA gene amplicons were acquired from the cecum contents and evaluated by next-generation sequencing.Results: A total of 2,539,288 sequences were generated with ~500 nucleotide read lengths. Firmicutes, Bacteroidetes, and Proteobacteria were the dominant phyla, occupying more than 96% of all three groups. <i>Lactobacillus, Bacteroides, Megasphaera</i>, and <i>Campylobacter</i> showed potential as biomarkers for each group. Particularly, <i>Lactobacillus</i> and <i>Bacteroides</i> were more abundant in the DON and ZEN groups than in the control. Additionally, 52,414 operational taxonomic units were detected in the three groups; those of <i>Bacteroides, Lactobacillus, Campylobacter</i>, and <i>Prevotella</i> were most dominant and significantly varied between groups. Hence, contamination of feed by DON and ZEN affected the cecum microbiota, while <i>Lactobacillus</i> and <i>Bacteroides</i> were highly abundant and positively influenced the host physiology.Conclusion: <i>Lactobacillus</i> and <i>Bacteroides</i> play key roles in the process of detoxification and improving the immune response. We, therefore, believe that these results may be useful for determining whether disturbances in the intestinal microflora, such as the toxic effects of DON and ZEN, can be treated by modulating the intestinal bacterial flora.

Toxins ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 347 ◽  
Author(s):  
Kondreddy Reddy ◽  
Jin Jeong ◽  
Jaeyong Song ◽  
Yookyung Lee ◽  
Hyun-Jeong Lee ◽  
...  

Deoxynivalenol (DON) and zearalenone (ZEN) can seriously affect animal health, with potentially severe economic losses. Previous studies have demonstrated that gut microbiota plays a significant role in detoxification. We analyzed the colon contents from three groups of pigs (fed either a standard diet, or a diet with 8 mg/kg DON or ZEN). Bacterial 16S rRNA gene amplicons were obtained from the colon contents, and sequenced using next-generation sequencing on the MiSeq platform. Overall, 2,444,635 gene sequences were generated, with ≥2000 sequences examined. Firmicutes and Bacteroidetes were the dominant phyla in all three groups. The sequences of Lactobacillus, Megasphaera, and Faecalibacterium genera, and the unclassified Clostridiaceae family, represented more than 1.2% of the total, with significantly different abundances among the groups. Lactobacillus was especially more abundant in the DON (7.6%) and ZEN (2.7%) groups than in the control (0.2%). A total of 48,346 operational taxonomic units (OTUs) were identified in the three groups. Two OTUs, classified as Lactobacillus, were the most dominant in the DON and ZEN groups. The abundances of the remaining OTUs were also significantly different among the groups. Thus, the mycotoxin-contaminated feed significantly affected the colon microbiota, especially Lactobacillus, which was the most abundant. Therefore, we speculate that Lactobacillus plays a major role in detoxification of these mycotoxins.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Sandra Reitmeier ◽  
Thomas C. A. Hitch ◽  
Nicole Treichel ◽  
Nikolaos Fikas ◽  
Bela Hausmann ◽  
...  

Abstract16S rRNA gene amplicon sequencing is a popular approach for studying microbiomes. However, some basic concepts have still not been investigated comprehensively. We studied the occurrence of spurious sequences using defined microbial communities based on data either from the literature or generated in three sequencing facilities and analyzed via both operational taxonomic units (OTUs) and amplicon sequence variants (ASVs) approaches. OTU clustering and singleton removal, a commonly used approach, delivered approximately 50% (mock communities) to 80% (gnotobiotic mice) spurious taxa. The fraction of spurious taxa was generally lower based on ASV analysis, but varied depending on the gene region targeted and the barcoding system used. A relative abundance of 0.25% was found as an effective threshold below which the analysis of spurious taxa can be prevented to a large extent in both OTU- and ASV-based analysis approaches. Using this cutoff improved the reproducibility of analysis, i.e., variation in richness estimates was reduced by 38% compared with singleton filtering using six human fecal samples across seven sequencing runs. Beta-diversity analysis of human fecal communities was markedly affected by both the filtering strategy and the type of phylogenetic distances used for comparison, highlighting the importance of carefully analyzing data before drawing conclusions on microbiome changes. In summary, handling of artifact sequences during bioinformatic processing of 16S rRNA gene amplicon data requires careful attention to avoid the generation of misleading findings. We propose the concept of effective richness to facilitate the comparison of alpha-diversity across studies.


Plant Disease ◽  
2021 ◽  
Author(s):  
Qi Wei ◽  
Jie Li ◽  
Shuai Yang ◽  
Wenzhong Wang ◽  
Fanxiang Min ◽  
...  

Common scab (CS) caused by Streptomyces spp. is a significant soilborne potato disease that results in tremendous economic losses globally. Identification of CS-associated species of the genus Streptomyces can enhance understanding of the genetic variation of these bacterial species and is necessary for the control of this epidemic disease. The present study isolated Streptomyces strain 6-2-1(1) from scabby potatoes in Keshan County, Heilongjiang Province, China. PCR analysis confirmed that the strain harbored the characteristic Streptomyces pathogenicity island (PAI) genes (txtA, txtAB, nec1, and tomA). Pathogenicity assays proved that the strain caused typical scab lesions on potato tuber surfaces and necrosis on radish seedlings and potato slices. Subsequently, the strain was systemically characterized at morphological, physiological, biochemical and phylogenetic levels. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 6-2-1(1) shared 99.86% sequence similarity with Streptomyces rhizophilus JR-41T, isolated initially from bamboo in rhizospheric soil in Korea. PCR amplification followed by Sanger sequencing of the 16S rRNA gene of 164 scabby potato samples collected in Heilongjiang Province from 2019 to 2020 demonstrated that approximately 2% of the tested samples were infected with S. rhizophilus. Taken together, these results demonstrate that S. rhizophilus is capable of causing potato CS disease and may pose a potential challenge to potato production in Heilongjiang Province of China.


1999 ◽  
Vol 37 (10) ◽  
pp. 3281-3290 ◽  
Author(s):  
Michael M. Tunney ◽  
Sheila Patrick ◽  
Martin D. Curran ◽  
Gordon Ramage ◽  
Donna Hanna ◽  
...  

In this study the detection rates of bacterial infection of hip prostheses by culture and nonculture methods were compared for 120 patients with total hip revision surgery. By use of strict anaerobic bacteriological practice during the processing of samples and without enrichment, the incidence of infection by culture of material dislodged from retrieved prostheses after ultrasonication (sonicate) was 22%. Bacteria were observed by immunofluorescence microscopy in 63% of sonicate samples with a monoclonal antibody specific forPropionibacterium acnes and polyclonal antiserum specific for Staphylococcus spp. The bacteria were present either as single cells or in aggregates of up to 300 bacterial cells. These aggregates were not observed without sonication to dislodge the biofilm. Bacteria were observed in all of the culture-positive samples, and in some cases in which only one type of bacterium was identified by culture, both coccoid and coryneform bacteria were observed by immunofluorescence microscopy. Bacteria from skin-flake contamination were readily distinguishable from infecting bacteria by immunofluorescence microscopy. Examination of skin scrapings did not reveal large aggregates of bacteria but did reveal skin cells. These were not observed in the sonicates. Bacterial DNA was detected in 72% of sonicate samples by PCR amplification of a region of the bacterial 16S rRNA gene with universal primers. All of the culture-positive samples were also positive for bacterial DNA. Evidence of high-level infiltration either of neutrophils or of lymphocytes or macrophages into associated tissue was observed in 73% of patients. Our results indicate that the incidence of prosthetic joint infection is grossly underestimated by current culture detection methods. It is therefore imperative that current clinical practice with regard to the detection and subsequent treatment of prosthetic joint infection be reassessed in the light of these results.


PLoS ONE ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. e0212474 ◽  
Author(s):  
Daniel E. Almonacid ◽  
Laurens Kraal ◽  
Francisco J. Ossandon ◽  
Yelena V. Budovskaya ◽  
Juan Pablo Cardenas ◽  
...  

2009 ◽  
Vol 75 (6) ◽  
pp. 1525-1533 ◽  
Author(s):  
Sonja N. Jeter ◽  
Colleen M. McDermott ◽  
Patricia A. Bower ◽  
Julie L. Kinzelman ◽  
Melinda J. Bootsma ◽  
...  

ABSTRACT This study investigated the occurrence and diversity of Bacteroidales fecal bacteria in gulls residing in the Great Lakes region. Members of this bacterial order have been widely employed as human and bovine host-specific markers of fecal pollution; however, few studies have focused on gulls, which can be a major source of fecal indicator bacteria and pathogens at beaches. We found a low but consistent occurrence of Bacteroidales in gulls at five beaches in three different counties spanning the Wisconsin shoreline of Lake Michigan. The percentages of gulls positive for Bacteroidales were 4 to 8% at beaches in the southern part of the state and 8 to 50% at beaches in the north. Sequencing of 931 clones from seven gull Bacteroidales 16S rRNA gene libraries revealed a large amount of diversity in both individual and pooled gull fecal samples. Two libraries constructed from pooled gull fecal samples (n = 5 and n = 6) did not have a greater richness of sequences than individual samples, suggesting that even within a single gull diversity is high and an extensive sequencing effort is needed to characterize the populations. Estimates of the numbers of operational taxonomic units (OTUs) for the libraries obtained using different similarity levels revealed a large amount of microdiveristy with a limited number of OTUs at the 95% similarity level. Gull sequences were clustered by the beach from which they were collected, suggesting that there were geographic effects on the distribution of Bacteriodales. More than 53% of the 16S rRNA gene sequences from gulls at the southern beaches were associated with the family Porphyromonadaceae, primarily the genus Parabacteroides, whereas sequences from gulls at the northern beaches were comprised of Bacteroidaceae and Prevotellaceae sequences. Comparison of gull sequences with sequences from goose, canine, raccoon, and sewage sources revealed distinct clusters of closely related gull sequences; however, these sequences were widely dispersed across a dendrogram that included all other sources, including previously characterized gull Bacteroidales from other studies, suggesting that geographic influence or simply sample representation plays a greater role in the observed population structure than strictly the host gut environment.


Aerobiologia ◽  
2012 ◽  
Vol 28 (4) ◽  
pp. 481-498 ◽  
Author(s):  
Ulla Li Zweifel ◽  
Åke Hagström ◽  
Karin Holmfeldt ◽  
Runar Thyrhaug ◽  
Camilla Geels ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document