scholarly journals The transcriptome of Listeria monocytogenes during co-cultivation with cheese rind bacteria suggests adaptation by induction of ethanolamine and 1,2-propanediol catabolism pathway genes

2020 ◽  
Author(s):  
Justin M. Anast ◽  
Stephan Schmitz-Esser
Keyword(s):  
Food Production ◽  
Virulence Genes ◽  
Listeriolysin O ◽  
Acid Biosynthesis ◽  
Adhesion Protein ◽  
Production Environments ◽  
Stress Survival ◽  
Genes Encoding ◽  
Stress Gene ◽  
Catabolism Pathway

AbstractThe survival of Listeria (L.) monocytogenes in foods and food production environments (FPE) is dependent on several genes that increase tolerance to stressors; this includes competing with intrinsic bacteria. We aimed to uncover genes that are differentially expressed (DE) in L. monocytogenes sequence type (ST) 121 strain 6179 when co-cultured with cheese rind bacteria. L. monocytogenes was cultivated in broth or on plates with either a Psychrobacter or Brevibacterium isolate from cheese rinds. RNA was extracted from co-cultures in broth after two or 12 hours and from plates after 24 and 72 hours. Broth co-cultivations with Brevibacterium or Psychrobacter yielded up to 392 and 601 DE genes, while plate co-cultivations significantly affected the expression of up to 190 and 485 L. monocytogenes genes, respectively. Notably, the transcription of virulence genes encoding the Listeria adhesion protein and Listeriolysin O were induced during plate and broth co-cultivations. The expression of several systems under the control of the global stress gene regulator, σB, increased during co-cultivation. A cobalamin-dependent gene cluster, responsible for the catabolism of ethanolamine and 1,2-propanediol, was upregulated in both broth and plate co-cultures conditions. Finally, a small non-coding (nc)RNA, Rli47, was induced after 72 hours of co-cultivation on plates and accounted for 50-90% of the total reads mapped to L. monocytogenes. A recent study has shown that Rli47 may contribute to L. monocytogenes stress survival by slowing growth during stress conditions through the suppression of branch-chained amino acid biosynthesis. We hypothesize that Rli47 may have an impactful role in the response of L. monocytogenes to co-cultivation by regulating a complex network of metabolic and virulence mechanisms.

scholarly journals Occurrence and molecular characterization of different virulence-associated genes of Cronobacter sakazakii isolates from some foods and dust samples

2018 ◽  
Vol 48 (8) ◽  
Author(s):  
Ülkü Demirci ◽  
İsmail Hakkı Tekiner ◽  
Burcu Çakmak ◽  
Haydar Özpınar
Keyword(s):  
Real Time ◽  
Food Production ◽  
Virulence Genes ◽  
Milk Powder ◽  
Rice Flour ◽  
Infants And Children ◽  
Cronobacter Sakazakii ◽  
Allowable Limit ◽  
Test Kit ◽  
Production Environments

ABSTRACT: Among the Cronobacter genus, Cronobacter sakazakii is the most common species posing a severe health risk for newborns, infants and children. Some infant formulas, cereal-based foods, and food production environments may be the potential reservoirs of C. sakazakii. This pathogen possesses different virulence factors encoded by different virulence genes. Therefore, characterizing these genes is important for distinguishing pathogenic strains from nonpathogenic ones. The objective of this study was to characterize some virulence genes [OmpA, OmpX, zpx, and Cpa] by real-time polymerase chain reaction (PCR) in C. sakazakii isolates from a total of 120 samples (20 each of milk powder, starch, rice flour, semolina, infant formula and dust samples from food production environments). Overall, 13 isolates (7 from milk powder, 2 rice flour, 1 semolina, and 3 dust) were cultured, identified by bioMérieux API® 20E test kit, and then subjected to real-time PCR application for screening the target virulence-associated genes. Our results showed that all of 13 isolates were positive for the virulence genes OmpA, OmpX, zpx, and Cpa. In summary, our study revealed that some of the analyzed foods and environmental samples were contaminated with pathogenic C. sakazakii with its virulence-associated markers, far above the allowable limit; and therefore, this level of contamination may pose a severe health threat for newborns, infants, and children.

Comparative Genomics of Three Novel Jumbo Bacteriophages Infecting Staphylococcus aureus

2021 ◽  
Author(s):  
Abby M. Korn ◽  
Andrew E. Hillhouse ◽  
Lichang Sun ◽  
Jason J. Gill
Keyword(s):  
Staphylococcus Aureus ◽  
Comparative Genomics ◽  
The United States ◽  
Genomic Diversity ◽  
Homing Endonucleases ◽  
Swine Production ◽  
Protein Coding ◽  
Vertical Inheritance ◽  
Production Environments ◽  
Genes Encoding

The majority of previously described Staphylococcus aureus bacteriophages belong to three major groups: P68-like podophages, Twort-like or K-like myophages, and a more diverse group of temperate siphophages. Here we present three novel S. aureus “jumbo” phages: MarsHill, Madawaska, and Machias. These phages were isolated from swine production environments in the United States and represent a novel clade of S. aureus myophage. The average genome size for these phages is ∼269 kb with each genome encoding ∼263 predicted protein-coding genes. Phage genome organization and content is similar to known jumbo phages of Bacillus , including AR9 and vB_BpuM-BpSp. All three phages possess genes encoding complete virion and non-virion RNA polymerases, multiple homing endonucleases, and a retron-like reverse transcriptase. Like AR9, all of these phages are presumed to have uracil-substituted DNA which interferes with DNA sequencing. These phages are also able to transduce host plasmids, which is significant as these phages were found circulating in swine production environments and can also infect human S. aureus isolates. Importance of work: This study describes the comparative genomics of three novel S. aureus jumbo phages: MarsHill, Madawaska, and Machias. These three S. aureus myophages represent an emerging class of S. aureus phage. These genomes contain abundant introns which show a pattern consistent with repeated acquisition rather than vertical inheritance, suggesting intron acquisition and loss is an active process in the evolution of these phages. These phages have presumably hypermodified DNA which inhibits sequencing by several different common platforms. Therefore, these phages also represent potential genomic diversity that has been missed due to the limitations of standard sequencing techniques. In particular, such hypermodified genomes may be missed by metagenomic studies due to their resistance to standard sequencing techniques. Phage MarsHill was found to be able to transduce host DNA at levels comparable to that found for other transducing S. aureus phages, making them a potential vector for horizontal gene transfer in the environment.

scholarly journals Virulence Genes and Molecular Typing of Different Groups of Escherichia coli O157 Strains in Cattle

2009 ◽  
Vol 75 (19) ◽  
pp. 6282-6291 ◽  
Author(s):  
István Tóth ◽  
Herbert Schmidt ◽  
Gábor Kardos ◽  
Zsuzsanna Lancz ◽  
Kristina Creuzburg ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Housekeeping Genes ◽  
Enzyme Analysis ◽  
Virulence Plasmid ◽  
O157 Strain ◽  
Pathogenic Potential ◽  
E Coli ◽  
Strain Collection ◽  
Genes Encoding

ABSTRACT Characterization of an Escherichia coli O157 strain collection (n = 42) derived from healthy Hungarian cattle revealed the existence of diverse pathotypes. Enteropathogenic E. coli (EPEC; eae positive) appeared to be the most frequent pathotype (n = 22 strains), 11 O157 strains were typical enterohemorrhagic E. coli (EHEC; stx and eae positive), and 9 O157 strains were atypical, with none of the key stx and eae virulence genes detected. EHEC and EPEC O157 strains all carried eae-gamma, tir-gamma, tccP, and paa. Other virulence genes located on the pO157 virulence plasmid and different O islands (O island 43 [OI-43] and OI-122), as well as espJ and espM, also characterized the EPEC and EHEC O157 strains with similar frequencies. However, none of these virulence genes were detected by PCR in atypical O157 strains. Interestingly, five of nine atypical O157 strains produced cytolethal distending toxin V (CDT-V) and carried genes encoding long polar fimbriae. Macro-restriction fragment enzyme analysis (pulsed-field gel electrophoresis) revealed that these E. coli O157 strains belong to four main clusters. Multilocus sequence typing analysis revealed that five housekeeping genes were identical in EHEC and EPEC O157 strains but were different in the atypical O157 strains. These results suggest that the Hungarian bovine E. coli O157 strains represent at least two main clones: EHEC/EPEC O157:H7/NM (nonmotile) and atypical CDT-V-producing O157 strains with H antigens different from H7. The CDT-V-producing O157 strains represent a novel genogroup. The pathogenic potential of these strains remains to be elucidated.

Virulence factors analysis and antibiotic resistance of uropathogenic Escherichia coli isolated from patients in northeast of Iran

2020 ◽  
Author(s):  
Mahdis Ghavidel ◽  
Tahere Gholamhosseini-Moghadam ◽  
Kimiya Nourian ◽  
Kiarash Ghazvini
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Virulence Genes ◽  
High Rate ◽  
Resistance Pattern ◽  
Antibiotics Resistance ◽  
Disk Diffusion Test ◽  
E Coli ◽  
Genes Encoding ◽  
Tract Infections

Background and Objectives: Escherichia coli is known to be the pathogen commonly isolated from those infected with uri- nary tract infections (UTIs). The aim of this study was to investigate the presence of E. coli virulence genes and antibiotics’ resistance pattern among clinical isolates in the Northeast of Iran. Relationships between virulence genes and antimicrobial resistances were studied as well. Materials and Methods: Three hundred isolates of E. coli were isolated from patients with UTIs that referred to Ghaem and Imam Reza hospitals (Mashhad, Iran) during August 2016 to February 2017. A multiplex PCR was employed to amplify the genes encoding pyelonephritis associated pili (pap), S-family adhesions (sfa), type1fimbriae (fimH) and aerobactin (aer). Disk diffusion test was performed to test the susceptibility of isolates to β-lactams, aminoglycosides, cephalosporins, quino- lone, fluoroquinolones, carbapenems and trimethoprim-sulfamethoxazole. Results: The PCR results identified the fimH in 78.4%, aer in 70.5%, sfa in 13.6% and the pap in 8.2% of isolates. The rates of antibiotic resistance of the isolates were as follows: 64.7% resistant to cephalosporins, 34% to trimethoprim-sul- famethoxazole, 31% to fluoroquinolones, 15.3% to aminoglycosides, 13.3% to β-lactams, 7.8% to quinolones and 4.4% to carbapenems. Significant relationships existed between pap and aer, pap and sfa, aer and fluoroquinolones also pap and cephalosporins. Conclusion: fimH and aer were found in > 50% of isolates suggesting the importance of both genes in UPEC. The majority of isolates had fimH as adhesion factor for colonization. Determining antibiotic resistance patterns in specific geographical areas is necessary for appropriate treatment of urinary tract infection. The high rate of resistance to cephalosporins is most likely due to incorrect drug administration

scholarly journals Isolation and Characterization of Potentially Pathogenic Antimicrobial-Resistant Escherichia coli Strains from Chicken and Pig Farms in Spain

2010 ◽  
Vol 76 (9) ◽  
pp. 2799-2805 ◽  
Author(s):  
Pilar Cortés ◽  
Vanessa Blanc ◽  
Azucena Mora ◽  
Ghizlane Dahbi ◽  
Jesús E. Blanco ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Phylogenetic Analyses ◽  
Virulence Gene ◽  
E Coli ◽  
Isolation And Characterization ◽  
Zoonotic Risk ◽  
Poultry Farms ◽  
Pig Farms ◽  
Genes Encoding

ABSTRACT To ascertain whether on animal farms there reside extended-spectrum β-lactamase (ESBL) and plasmidic class C β-lactamase-producing Escherichia coli isolates potentially pathogenic for humans, phylogenetic analyses, pulsed-field gel electrophoresis (PFGE) typing, serotyping, and virulence genotyping were performed for 86 isolates from poultry (57 isolates) and pig (29 isolates) farms. E. coli isolates from poultry farms carried genes encoding enzymes of the CTX-M-9 group as well as CMY-2, whereas those from pig farms mainly carried genes encoding CTX-M-1 enzymes. Poultry and pig isolates differed significantly in their phylogenetic group assignments, with phylogroup A predominating in pig isolates and phylogroup D predominating in avian isolates. Among the 86 farm isolates, 23 (26.7%) carried two or more virulence genes typical of extraintestinal pathogenic E. coli (ExPEC). Of these, 20 were isolated from poultry farms and only 3 from pig farms. Ten of the 23 isolates belonged to the classic human ExPEC serotypes O2:H6, O2:HNM, O2:H7, O15:H1, and O25:H4. Despite the high diversity of serotypes and pulsotypes detected among the 86 farm isolates, 13 PFGE clusters were identified. Four of these clusters contained isolates with two or more virulence genes, and two clusters exhibited the classic human ExPEC serotypes O2:HNM (ST10) and O2:H6 (ST115). Although O2:HNM and O2:H6 isolates of human and animal origins differed with respect to their virulence genes and PFGE pulsotypes, the O2:HNM isolates from pigs showed the same sequence type (ST10) as those from humans. The single avian O15:H1 isolate was compared with human clinical isolates of this serotype. Although all were found to belong to phylogroup D and shared the same virulence gene profile, they differed in their sequence types (ST362-avian and ST393-human) and PFGE pulsotypes. Noteworthy was the detection, for the first time, in poultry farms of the clonal groups O25b:H4-ST131-B2, producing CTX-M-9, and O25a-ST648-D, producing CTX-M-32. The virulence genes and PFGE profiles of these two groups were very similar to those of clinical human isolates. While further studies are required to determine the true zoonotic potential of these clonal groups, our results emphasize the zoonotic risk posed especially by poultry farms, but also by pig farms, as reservoirs of ESBL- and CMY-2-encoding E. coli.

scholarly journals Adaptation of Corynebacterium glutamicum to Ammonium Limitation: a Global Analysis Using Transcriptome and Proteome Techniques

2005 ◽  
Vol 71 (5) ◽  
pp. 2391-2402 ◽  
Author(s):  
Maike Silberbach ◽  
Mathias Schäfer ◽  
Andrea T. Hüser ◽  
Jörn Kalinowski ◽  
Alfred Pühler ◽  
...  
Keyword(s):  
Corynebacterium Glutamicum ◽  
Metabolic Pathways ◽  
Ribosomal Proteins ◽  
Nitrogen Assimilation ◽  
Global Analysis ◽  
Cellular Transport ◽  
Acid Biosynthesis ◽  
Limited Growth ◽  
Rate Dependent ◽  
Genes Encoding

ABSTRACT Theresponse of Corynebacterium glutamicum to ammonium limitation was studied by transcriptional and proteome profiling of cells grown in a chemostat. Our results show that ammonium-limited growth of C. glutamicum results in a rearrangement of the cellular transport capacity, changes in metabolic pathways for nitrogen assimilation, amino acid biosynthesis, and carbon metabolism, as well as a decreased cell division. Since transcription at different growth rates was studied, it was possible to distinguish specific responses to ammonium limitation and more general, growth rate-dependent alterations in gene expression. The latter include a number of genes encoding ribosomal proteins and genes for FoF1-ATP synthase subunits.

scholarly journals Comparative RNA-seq-Based Transcriptome Analysis of the Virulence Characteristics of Methicillin-Resistant and -Susceptible Staphylococcus pseudintermedius Strains Isolated from Small Animals

2015 ◽  
Vol 60 (2) ◽  
pp. 962-967 ◽  
Author(s):  
Natacha Couto ◽  
Adriana Belas ◽  
Manuela Oliveira ◽  
Paulo Almeida ◽  
Carla Clemente ◽  
...  
Keyword(s):  
Virulence Genes ◽  
Expression Profiles ◽  
Brain Heart Infusion ◽  
Surface Proteins ◽  
Rna Seq ◽  
Staphylococcus Pseudintermedius ◽  
Methicillin Resistant ◽  
Content Type ◽  
Genes Encoding

ABSTRACTStaphylococcus pseudintermediusis often associated with pyoderma, which can turn into a life-threatening disease. The dissemination of highly resistant isolates has occurred in the last 10 years and has challenged antimicrobial treatment of these infections considerably. We have compared the carriage of virulence genes and biofilm formation between methicillin-resistant and methicillin-susceptibleS. pseudintermedius(MRSP and MSSP, respectively) isolates and theirin vitrogene expression profiles by transcriptome sequencing (RNA-seq). Isolates were relatively unevenly distributed among the fouragrgroups, andagrtype III predominated in MRSP. Five virulence genes were detected in all isolates. Only thespsOgene was significantly associated with MSSP isolates (P= 0.04). All isolates produced biofilm in brain heart infusion broth (BHIB)–4% NaCl. MSSP isolates produced more biofilm on BHIB and BHIB–1% glucose media than MRSP isolates (P= 0.03 andP= 0.02, respectively). Virulence genes encoding surface proteins and toxins (spsA,spsB,spsD,spsK,spsL,spsN,nucC,coa, andluk-I) and also prophage genes (encoding phage capsid protein, phage infection protein, two phage portal proteins, and a phage-like protein) were highly expressed in the MRSP isolate (compared with the MSSP isolate), suggesting they may play a role in the rapid and widespread dissemination of MRSP. This study indicates that MRSP may upregulate surface proteins, which may increase the adherence of MRSP isolates (especially sequence type 71 [ST71]) to corneocytes. MSSP isolates may have an increased ability to form biofilm under acidic circumstances, through upregulation of the entirearcoperon. Complete understanding ofS. pseudintermediuspathogenesis and host-pathogen signal interaction during infections is critical for the treatment and prevention ofS. pseudintermediusinfections.

scholarly journals Molecular Investigation of hemolytic phospholipase C Encoding Genes in Clinical Isolates of Pseudomonas aeruginosa

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Rasha Hadi Saleh ◽  
Habeeb S Naher ◽  
Mohammed AK Al-saadi
Keyword(s):  
Phospholipase C ◽  
Virulence Genes ◽  
Clinical Isolates ◽  
Clinical Samples ◽  
Burn Wound ◽  
Molecular Investigation ◽  
Genes Encoding ◽  
Stool Samples ◽  
Polymerase Chain ◽  
Encoding Genes

This study is aimed to isolate P.aeruginosa from different clinical cases and to detect the prevalence of virulence genes encoding hemolytic phospholipase C(plcH)in these clinical isolates. In this study a total of 422 clinical samples including burn,wound,ear,urine,abscess and stool were aseptically taken from out- and inpatients who admitted into two hospitals in Hilla City (Teaching Al-Hilla Hospital and Babylon Hospital for Maternity and children during a period of three months. All samples were subjected to bacterial cultivation for the isolation of P.aeruginosa. The isolated P.aeruginosa was diagnosed depended on morphological,biochemical and molecular standard characteristics. Hemolytic phospholipase Cencoding genes(plcH) were detected by PCR and the amplification products were separated in 1% agarose gels containing ethidium bromide. Out of 422 samples,P.aeruginosa was isolated from 54 samples (12.8%). The distribution of these isolates were: 22 (55%) from burn samples,2; (50%) from diabitics foot samples,8 (14.8%) from wound samples, 8 (32%) from ear samples,3 (11%) from abscess samples, 7 (4%) from stool samples,4 (4%) from urine samples and 0 sputum samples. The genotypic properties of hemolytic phospholipase C (plcH )toxins was detected by polymerase chain reaction (PCR). The results of this study revealed that(plcH )gene found in 13/20 (65%)of isolates.

scholarly journals Optimization of (S)-3-Hydroxybutyric Acid Biosynthesis from Glucose through the Reversed Fatty Acid β-Oxidation Pathway by Recombinant Escherichia coli Strains

2021 ◽  
Vol 57 (2) ◽  
pp. 161-169
Author(s):  
A. Yu. Gulevich ◽  
A. Yu. Skorokhodova ◽  
V. G. Debabov
Keyword(s):  
Escherichia Coli ◽  
Fatty Acid ◽  
Product Yield ◽  
Target Product ◽  
Hydroxybutyric Acid ◽  
Acid Biosynthesis ◽  
Gene Encoding ◽  
Oxidation Pathway ◽  
Genes Encoding ◽  
Primary Evaluation

Abstract The microaerobic synthesis of 3-hydroxybutyric acid by the Escherichia coli strain BOX3.1 ∆4 PL-atoB PL-tesB (MG1655 lacIQ, ∆ackA-pta, ∆poxB, ∆ldhA, ∆adhE, ∆fadE, PL-SDphi10-atoB, Ptrc-ideal-4-SDphi10-fadB, PL-SDphi10-tesB), which was previously directly engineered for the biosynthesis of the target compound from glucose through the reversed fatty acid β-oxidation pathway, was studied. A target product yield of 0.12 mol/mol was achieved. Inactivation of the nonspecific YciA thioesterase gene in the strain led to an increase in the yield of 3-hydroxybutyric acid to 0.15 mol/mol. For the optimization of biosynthesis of target product the strain MG∆4 PL-tesB (MG1655 ∆ackA-pta, ∆poxB, ∆ldhA, ∆adhE, PL-SDphi10-tesB) was engineered, and the genes encoding key enzymes of fatty acid β-oxidation were overexpressed in the strain from the plasmid pMW118m-atoB-fadB. The level of microaerobic synthesis of 3-hydroxybutyric acid by the strain MG∆4 PL-tesB (pMW118m-atoB-fadB) achieved in primary evaluation conditions reached 0.35 mol/mol. Inactivation in the strain of the gene of nonspecific thioesterase YciA led to only minor decrease in acetate byproduction. Further inactivation in the strain of gene encoding nonspecific thioesterase YdiI had virtually no effect on the level of synthesis of side products. Cultivation of the constructed strain MG∆4 PL-tesB ∆yciA (pMW118m-atoB-fadB) in bioreactor under the controlled conditions ensured achievement of a yield of 3‑hydroxybutyric acid amounting to 0.75 mol/mol.

scholarly journals Bacteriocin activity of enterococci and presence of genes related to pathogenesis

2012 ◽  
Vol 30 (No. 4) ◽  
pp. 330-335 ◽  
Author(s):  
K. Trivedi ◽  
R. Sedmíková ◽  
R. Karpíšková
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Listeria Monocytogenes ◽  
Virulence Genes ◽  
Bacteriocin Production ◽  
Bacteriocin Activity ◽  
Antimicrobial Substances ◽  
Layer Technique ◽  
Genes Encoding ◽  
The Individual

In total 228 enterococci strains isolated from food were studied. Enterococcus faecalis, E. faecium, and E. casseliflavus were found to be the dominant strains while E. durans and E. mundtii were present in a smaller extent. Antimicrobial activity determined by double layer technique revealed that 150 (65.7%) strains showed antimicrobial activity against the individual tested pathogenic strains of Listeria monocytogenes, Staphylococcus aureus, and methicilin resistant S. aureus (MRSA). Cell-free neutralised supernatants (CFNS) were prepared from 150 potential bacteriocin producers. Of these 150, CFNS 107 (71.3%) strains were active in the bacteriocin production against one or more pathogenic strains tested. S. aureus and MRSA were found to be more sensitive to the antimicrobial substances than L. monocytogenes. Multiplex PCR for the detection of seven virulence genes in bacteriocin producing strains showed that 47.6% of strains were able to amplify one or more virulence genes. E. faecalis was the most virulent species. The presence of tyrdc gene was seen in all bacteriocin producing strains. None of the strains carried genes encoding the resistance to vancomycin.  

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