scholarly journals Assessment of Safety and Probiotic Traits of Enterococcus durans OSY-EGY, Isolated From Egyptian Artisanal Cheese, Using Comparative Genomics and Phenotypic Analyses

2020 ◽  
Vol 11 ◽  
Author(s):  
Walaa E. Hussein ◽  
Ahmed G. Abdelhamid ◽  
Diana Rocha-Mendoza ◽  
Israel García-Cano ◽  
Ahmed E. Yousef

An Enterococcus durans strain, designated OSY-EGY, was previously isolated from artisanal cheese. In this work, comparative genomic and phenotypic analyses were utilized to assess the safety characteristics and probiotic traits of the bacterium. The comparative genomic analysis revealed that the strain is distantly related to potentially pathogenic Enterococcus spp. The genome was devoid of genes encoding acquired antibiotic resistance or marker virulence factors associated with Enterococcus spp. Phenotypically, the bacterium is susceptible to vancomycin, ampicillin, tetracycline, chloramphenicol, and aminoglycosides and does not have any hemolytic or gelatinase activity, or cytotoxic effect on Caco-2 cells. Altogether, these findings confirm the lack of hazardous traits in E. durans OSY-EGY. Mining E. durans OSY-EGY genome, for probiotic-related sequences, revealed genes associated with acid and bile salts tolerance, adhesion, competitiveness, antioxidant activitiy, antimicrobial activity, essential amino acids production, and vitamins biosynthesis. Phenotypically, E. durans OSY-EGY was tolerant to acidic pH (3.0), and presence of 0.3% bile salts. The bacterium showed adhesion capability to Caco-2 cells, cholesterol-lowering effect, DPPH scavenging activity, and antimicrobial activity against several Gram-positive pathogenic bacteria. Based on the current work, we propose that E. durans OSY-EGY is a potentially safe strain with desirable probiotic and antimicrobial traits. Thus, the investigated strain could be a promising candidate for several industrial applications.

2021 ◽  
Vol 12 ◽  
Author(s):  
Yi Zhou ◽  
Lu Shi ◽  
Juan Wang ◽  
Jia Yuan ◽  
Jin Liu ◽  
...  

To evaluate the probiotic characteristics and safety of Enterococcus durans isolate A8-1 from a fecal sample of a healthy Chinese infant, we determined the tolerance to low pH, survival in bile salts and NaCl, adhesion ability, biofilm formation, antimicrobial activity, toxin gene distribution, hemolysis, gelatinase activity, antibiotic resistance, and virulence to Galleria mellonella and interpreted the characters by genome resequencing. Phenotypically, E. durans A8-1 survived at pH 5.0 in 7.0% NaCl and 3% bile salt under aerobic and anaerobic condition. The bacterium had higher adhesion ability toward mucin, collagen, and Bovine Serum Albumin (BSA) in vitro and showed high hydrophobicity (79.2% in chloroform, 49.2% in xylene), auto-aggregation activity (51.7%), and could co-aggregate (66.2%) with Salmonella typhimurium. It had adhesion capability to intestinal epithelial Caco-2 cells (38.74%) with moderate biofilm production and antimicrobial activity against several Gram-positive pathogenic bacteria. A8-1 can antagonize the adhesion of S. typhimurium ATCC14028 on Caco-2 cells to protect the integrity of the cell membrane by detection of lactate dehydrogenase (LDH) and AKP activities. A8-1 also helps the cell relieve the inflammation induced by lipopolysaccharide by reducing the expression of cytokine IL-8 (P = 0.002) and TNF-α (P > 0.05), and increasing the IL-10 (P < 0.001). For the safety evaluation, A8-1 showed no hemolytic activity, no gelatinase activity, and had only asa1 positive in the seven detected virulence genes in polymerase chain reaction (PCR), whereas it was not predicted in the genome sequence. It was susceptible to benzylpenicillin, ampicillin, ciprofloxacin, levofloxacin, moxifloxacin, tigecycline, nitrofurantoin, linezolid, vancomycin, erythromycin, and quinupristin/dalofopine except clindamycin, which was verified by the predicted lasA, lmrB, lmrC, and lmrD genes contributing to the clindamycin resistance. The virulence test of G. mellonella showed that it had toxicity lower than 10% at 1 × 107 CFU. According to the results of these evaluated attributes, E. durans strain A8-1 could be a promising probiotic candidate for applications.


2020 ◽  
Vol 117 (50) ◽  
pp. 31979-31986
Author(s):  
Vincent G. Martinson ◽  
Ryan M. R. Gawryluk ◽  
Brent E. Gowen ◽  
Caitlin I. Curtis ◽  
John Jaenike ◽  
...  

Obligate symbioses involving intracellular bacteria have transformed eukaryotic life, from providing aerobic respiration and photosynthesis to enabling colonization of previously inaccessible niches, such as feeding on xylem and phloem, and surviving in deep-sea hydrothermal vents. A major challenge in the study of obligate symbioses is to understand how they arise. Because the best studied obligate symbioses are ancient, it is especially challenging to identify early or intermediate stages. Here we report the discovery of a nascent obligate symbiosis in Howardula aoronymphium, a well-studied nematode parasite of Drosophila flies. We have found that H. aoronymphium and its sister species harbor a maternally inherited intracellular bacterial symbiont. We never find the symbiont in nematode-free flies, and virtually all nematodes in the field and the laboratory are infected. Treating nematodes with antibiotics causes a severe reduction in fly infection success. The association is recent, as more distantly related insect-parasitic tylenchid nematodes do not host these endosymbionts. We also report that the Howardula nematode symbiont is a member of a widespread monophyletic group of invertebrate host-associated microbes that has independently given rise to at least four obligate symbioses, one in nematodes and three in insects, and that is sister to Pectobacterium, a lineage of plant pathogenic bacteria. Comparative genomic analysis of this group, which we name Candidatus Symbiopectobacterium, shows signatures of genome erosion characteristic of early stages of symbiosis, with the Howardula symbiont’s genome containing over a thousand predicted pseudogenes, comprising a third of its genome.


Gut Pathogens ◽  
2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Thongpan Leangapichart ◽  
Linda Hadjadj ◽  
Philippe Gautret ◽  
Jean-Marc Rolain

Abstract Background Shewanella xiamenensis has been reported in water environment and in patients and can act as the originator of oxacillinase in gram-negative bacteria. In order to assess genome plasticity and its functional properties related diarrhea symptoms in pilgrim, comparisons of draft genome sequences of the two isolates were conducted with other closely related genomes. Results We isolated S. xiamenensis 111B and 111D strains from a pilgrim before travels to the Hajj and during travels with diarrhea symptom, respectively. Whole-genome sequencing showed that draft genome size of 111B strain was 5,008,191 bp, containing 49 kb of a putative plasmid. The genome size of 111D was 4,964,295 bp containing 225 kb of a putative plasmid that shared the backbone sequences with the hospital wastewater strain T17. Comparatively, two Hajj strains are identical at 97.3% identity and 98.7% coverage. They are closely related to river water strain, AS58 by SNPs analysis. Notably, a novel blaOXA-48 allele blaOXA-547 was identified in 111D, sharing 99.5% identity with blaOXA-546 and blaOXA-894. Multiple copies of virulence specific genes, such as capsular polysaccharide biosynthesis, O-antigen and lasB (vibriolysin related gene) have been identified specifically in 111D, but absent in 111B strain. Conclusions The whole genome sequences of S. xiamenensis strain 111B and 111D, including comparative genomic analysis, highlight here the potential for virulence factors that might be related to the cause of diarrhea in humans and also indicate the possible acquisition of pathogenic bacteria, including antibiotic resistance genes or plasmids during the Hajj.


2021 ◽  
Vol 12 ◽  
Author(s):  
Shenglei Yuan ◽  
Yundan Wang ◽  
Fangqing Zhao ◽  
Le Kang

The genus Weissella is attracting an increasing amount of attention because of its multiple functions and probiotic potential. In particular, the species Weissella confusa is known to have great potential in industrial applications and exhibits numerous biological functions. However, the knowledge on this bacterium in insects is not investigated. Here, we isolated and identified W. confusa as the dominant lactic acid bacteria in the gut of the migratory locust. We named this strain W. confusa LM1, which is the first genome of an insect-derived W. confusa strain with one complete chromosome and one complete plasmid. Among all W. confusa strains, W. confusa LM1 had the largest genome. Its genome was the closest to that of W. confusa 1001271B_151109_G12, a strain from human feces. Our results provided accurate evolutionary relationships of known Weissella species and W. confusa strains. Based on genomic analysis, the pan-genome of W. confusa is in an open state. Most strains of W. confusa had the unique genes, indicating that these strains can adapt to different ecological niches and organisms. However, the variation of strain-specific genes did represent significant correlations with their hosts and ecological niches. These strains were predicted to have low potential to produce secondary metabolites. Furthermore, no antibiotic resistance genes were identified. At the same time, virulence factors associated with toxin production and secretion system were not found, indicating that W. confusa strains were not sufficient to perform virulence. Our study facilitated the discovery of the functions of W. confusa LM1 in locust biology and their potential application to locust management.


2016 ◽  
Author(s):  
VICTOR GASPAROTTO CAPONE ◽  
Andreas Karoly Gombert ◽  
Jose Valdo Madeira Junior ◽  
JULIANA JOSÉ

Author(s):  
Qiqi Pan ◽  
Shi Cen ◽  
Leilei Yu ◽  
Fengwei Tian ◽  
Jianxin Zhao ◽  
...  

Lactobacillus plantarum, a widely used probiotic in the food industry, exists in diverse habitats, which has led to its niche-specific genetic evolution. However, the relationship between this type of genetic evolution and the bacterial phenotype remains unclear. Here, six L. plantarum strains derived from paocai and human feces were analyzed at the genomic and phenotypic levels to investigate the features of adaptive evolution in different habitats. A comparative genomic analysis showed that 93 metabolism-related genes underwent structural variations (SVs) during adaptive evolution, including genes responsible for carbohydrate, lipid, amino acid, inorganic ion and coenzyme transport and metabolism, and energy production and conversion. Notably, seven virulence factor-related genes in strains from both habitats showed SVs — similar to the pattern found in the orthologous virulence genes of pathogenic bacteria shared similar niches, suggesting the possibility of horizontal gene transfer. These genomic variations further influenced the metabolic abilities of strains and their interactions with the commensal microbiota in the host intestine. Compared with the strains from feces, those from paocai exhibited a shorter stagnation period and a higher growth rate in a diluted paocai solution because of variations in functional genes. In addition, opposite correlations were identified between the relative abundances of L. plantarum strains and the genus Bifidobacterium in two media inoculated with strains from the two habitats. Overall, our findings revealed that the niche-specific genetic evolution of L. plantarum strains is associated with their fermentation abilities and physiological functions in host gut health. This knowledge can help guiding the exploration and application of probiotics from the specific niches-based probiotic exploitation.


2009 ◽  
Vol 1 (2) ◽  
Author(s):  
Risa Nofiani ◽  
Siti Nurbetty ◽  
Ajuk Sapar

<p>The increase of issues on the antibiotics resistant pathogenic bacteria has triggered high exploration for new antimicrobial compounds. One of the potential sources is sponge-associated bacteria. The aim of this study was to get sponge-associated bacteria extract containing antimicrobial activities. On the basis screening of antimicrobial activity using by streaking on agar medium, there were two potential isolates with antimicrobial activities namely LCS1 and LCS2. The two isolates were cultivated,then secondary metabolite product were extracted using methanol as a solvent. Minimum inhibitory concentrations (MICs) of extract LCS 1 were 1,000 μg/well for S. aureus, 950 μg/well for Salmonella sp.and 800 μg/well for Bacillus subtilis. Minimum inhibitory concentrations of extract LCS 2 were 500 μg/well for S. aureus, 1,050 μg/well for Salmonella sp., 750 μg/well for Bacillus subtilis, 350 μg/well for P. aeruginosa, 750 μg/sumur terhadap B. subtilis. Based on the MIC values, the two assay extracts have a relatively low antimicrobial activity.</p> <p>Keywords:Antimicrobial,Sponges associated bacteria,MICs</p>


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