scholarly journals A Novel Methicillin-ResistantStaphylococcus aureust11469 and a Poultry Endemic Strain t002 (ST5) Are Present in Chicken in Ebonyi State, Nigeria

2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Amos Nworie ◽  
Azi S. Onyema ◽  
Simon I. Okekpa ◽  
Michael O. Elom ◽  
Nse O. Umoh ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factor ◽  
Molecular Typing ◽  
Staphylococcal Infection ◽  
Sequence Type ◽  
Antimicrobial Use ◽  
Putative Virulence Factor ◽  
The Novel ◽  
Pathogenic Potential ◽  
Endemic Strain

Background. The changing epidemiology of methicillin-resistantStaphylococcus aureus(MRSA) from a hospital-associated pathogen to an organism commonly found in the community and in livestock reflects an organism well-equipped to survive in diverse environments and adjust to different environmental conditions including antimicrobial use.Methods. We investigated the molecular epidemiology ofS. aureusand MRSA in poultry in Ebonyi State, Nigeria. Samples were collected from 1800 birds on 9 different farms within the state. Positive isolates were tested for antibiotic susceptibility and molecular typing.Results. Prevalence in birds was 13.7% (247/1800). MRSA prevalence in poultry was 0.8%. The prevalence of MRSA in broilers and layers was 1.2% and 0.4%, respectively. All tested isolates were susceptible to vancomycin. Molecular analysis of the isolates revealed 3spatypes: t002, t084, and a novelspatype, t11469. The novelspatype t11469 belonged to sequence type ST5.Conclusion. The detection of t002 in chicken suggests the presence of livestock-associated MRSA in poultry in Ebonyi State. The detection of the newspatype t11469 in poultry that has not been characterised to ascertain its pathogenic potential remains a cause for concern, especially as some were found to carry PVL genes, a putative virulence factor in staphylococcal infection.

scholarly journals Virulence factor landscape of a Staphylococcus aureus sequence type 45 strain, MCRF184

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Vijay Aswani ◽  
Fares Najar ◽  
Madhulatha Pantrangi ◽  
Bob Mau ◽  
William R. Schwan ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factor ◽  
Sequence Type

scholarly journals Design, Validation, and Application of a Seven-Strain Staphylococcus aureus PCR Product Microarray for Comparative Genomics

2005 ◽  
Vol 71 (11) ◽  
pp. 7504-7514 ◽  
Author(s):  
Adam A. Witney ◽  
Gemma L. Marsden ◽  
Matthew T. G. Holden ◽  
Richard A. Stabler ◽  
Sarah E. Husain ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Comparative Genomics ◽  
Microarray Data ◽  
Correct Identification ◽  
The Novel ◽  
Pathogenic Potential ◽  
Reading Frame ◽  
Pcr Product ◽  
Wide Range ◽  
Design Build

ABSTRACT Bacterial comparative genomics has been revolutionized by microarrays, but the power of any microarray is dependent on the number and diversity of gene reporters it contains. Staphylococcus aureus is an important human pathogen causing a wide range of invasive and toxin-mediated diseases, and more than 20% of the genome of any isolate consists of variable genes. Seven whole-genome sequences of S. aureus are available, and we exploited this rare opportunity to design, build, and validate a comprehensive, nonredundant PCR product microarray carrying reporters that represent every predicted open reading frame (3,623 probes). Such a comprehensive microarray necessitated a novel design strategy. Validation with the seven sequenced strains showed correct identification of 93.9% of genes present or absent/divergent but was dependent on the method of analysis chosen. Microarray data were highly reproducible, reducing the need for many replicate slides. Interpretation of microarray data was enhanced by focusing on the major areas of variation—the presence or absence of mobile genetic elements (MGEs). We compiled “composite genomes” of every individual MGE and visualized their distribution. This allowed the sensitive discrimination of related isolates, including the first clear description of how isolates of the same clone of epidemic methicillin-resistant S. aureus differ substantially in their carriage of MGEs. These MGEs carry virulence and resistance genes, suggesting differences in pathogenic potential. The novel methods of design and interpretation of data generated from this microarray will enable further studies of S. aureus evolution, epidemiology, and pathogenesis.

scholarly journals Identification of a Plasmid-Borne Resistance Gene Cluster Comprising the Resistance Genes erm(T), dfrK, and tet(L) in a Porcine Methicillin-Resistant Staphylococcus aureus ST398 Strain

2009 ◽  
Vol 54 (2) ◽  
pp. 915-918 ◽  
Author(s):  
Kristina Kadlec ◽  
Stefan Schwarz
Keyword(s):  
Staphylococcus Aureus ◽  
Gene Cluster ◽  
Resistance Gene ◽  
Streptococcus Pyogenes ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Tetracycline Resistance ◽  
Sequence Type ◽  
The Novel ◽  
Methicillin Resistant ◽  
Resistance Gene Cluster

ABSTRACT A novel plasmid-borne resistance gene cluster comprising the genes erm(T) for macrolide-lincosamide-streptogramin B resistance, dfrK for trimethoprim resistance, and tet(L) for tetracycline resistance was identified in a porcine methicillin-resistant Staphylococcus aureus sequence type 398 (ST398) strain. This erm(T)-dfrK-tet(L) region was flanked by copies of the novel IS element ISSau10. The erm(T) region resembled that of Streptococcus pyogenes plasmid pRW35. The erm(T) gene of pKKS25 was expressed constitutively due to a 57-bp deletion in the erm(T) translational attenuator.

scholarly journals Molecular typing revealed the emergence of pvl-positive sequence type 22 methicillin-susceptible Staphylococcus aureus in Urumqi, Northwestern China

2019 ◽  
Vol Volume 12 ◽  
pp. 1719-1728 ◽  
Author(s):  
Wenchang Yuan ◽  
Jianhua Liu ◽  
Youchao Zhan ◽  
Li Wang ◽  
Yanqiong Jiang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Molecular Typing ◽  
Sequence Type ◽  
Northwestern China ◽  
Positive Sequence

scholarly journals Unraveling the Impact of Secreted Proteases on Hypervirulence in Staphylococcus aureus

mBio ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Brittney D. Gimza ◽  
Jessica K. Jackson ◽  
Andrew M. Frey ◽  
Bridget G. Budny ◽  
Dale Chaput ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factors ◽  
Virulence Factor ◽  
Extracellular Proteases ◽  
Pathogenic Potential ◽  
Content Type ◽  
Secreted Proteases ◽  
The Individual ◽  
Necessary And Sufficient ◽  
The Impact

ABSTRACT Staphylococcus aureus controls the progression of infection through the coordinated production of extracellular proteases, which selectively modulate virulence determinant stability. This is evidenced by our previous finding that a protease-null strain has a hypervirulent phenotype in a murine model of sepsis, resulting from the unchecked accumulation of virulence factors. Here, we dissect the individual roles of these proteases by constructing and assessing the pathogenic potential of a combinatorial protease mutant library. When strains were constructed bearing increasing numbers of secreted proteases, we observed a variable impact on infectious capacity, where some exhibited hypervirulence, while others phenocopied the wild-type. The common thread for hypervirulent strains was that each lacked both aureolysin and staphopain A. Upon assessment, we found that the combined loss of these two enzymes alone was necessary and sufficient to engender hypervirulence. Using proteomics, we identified a number of important secreted factors, including SPIN, LukA, Sbi, SEK, and PSMα4, as well as an uncharacterized chitinase-related protein (SAUSA300_0964), to be overrepresented in both the aur scpA and the protease-null mutants. When assessing the virulence of aur scpA SAUSA300_0964 and aur scpA lukA mutants, we found that hypervirulence was completely eliminated, whereas aur scpA spn and aur scpA sek strains elicited aggressive infections akin to the protease double mutant. Collectively, our findings shed light on the influence of extracellular proteases in controlling the infectious process and identifies SAUSA300_0964 as an important new component of the S. aureus virulence factor arsenal. IMPORTANCE A key feature of the pathogenic success of S. aureus is the myriad virulence factors encoded within its genome. These are subject to multifactorial control, ensuring their timely production only within an intended infectious niche. A key node in this network of control is the secreted proteases of S. aureus, who specifically and selectively modulate virulence factor stability. In our previous work we demonstrated that deletion of all 10 secreted proteases results in hypervirulence, since virulence factors exist unchecked, leading to overly aggressive infections. Here, using a combinatorial collection of protease mutants, we reveal that deletion of aureolysin and staphopain A is necessary and sufficient to elicit hypervirulence. Using proteomic techniques, we identify the collection of virulence factors that accumulate in hypervirulent protease mutants, and demonstrate that a well-known toxin (LukA) and an entirely novel secreted element (SAUSA300_0964) are the leading contributors to deadly infections observed in protease-lacking strains.

scholarly journals MetR-Regulated Vibrio cholerae Metabolism Is Required for Virulence

mBio ◽  
2012 ◽  
Vol 3 (5) ◽  
Author(s):  
Ryan W. Bogard ◽  
Bryan W. Davies ◽  
John J. Mekalanos
Keyword(s):  
Amino Acid ◽  
Vibrio Cholerae ◽  
Virulence Factor ◽  
Current Knowledge ◽  
Intestinal Colonization ◽  
Wild Type ◽  
Pathogenic Potential ◽  
Content Type ◽  
Mouse Intestine

ABSTRACTLysR-type transcriptional regulators (LTTRs) are the largest, most diverse family of prokaryotic transcription factors, with regulatory roles spanning metabolism, cell growth and division, and pathogenesis. Using a sequence-defined transposon mutant library, we screened a panel ofV. choleraeEl Tor mutants to identify LTTRs required for host intestinal colonization. Surprisingly, out of 38 LTTRs, only one severely affected intestinal colonization in the suckling mouse model of cholera: the methionine metabolism regulator, MetR. Genetic analysis of genes influenced by MetR revealed thatglyA1andmetJwere also required for intestinal colonization. Chromatin immunoprecipitation of MetR and quantitative reverse transcription-PCR (qRT-PCR) confirmed interaction with and regulation ofglyA1, indicating that misregulation ofglyA1is likely responsible for the colonization defect observed in themetRmutant. TheglyA1mutant was auxotrophic for glycine but exhibited wild-type trimethoprim sensitivity, making folate deficiency an unlikely cause of its colonization defect. MetJ regulatory mutants are not auxotrophic but are likely altered in the regulation of amino acid-biosynthetic pathways, including those for methionine, glycine, and serine, and this misregulation likely explains its colonization defect. However, mutants defective in methionine, serine, and cysteine biosynthesis exhibited wild-type virulence, suggesting that these amino acids can be scavenged in vivo. Taken together, our results suggest that glycine biosynthesis may be required to alleviate an in vivo nutritional restriction in the mouse intestine; however, additional roles for glycine may exist. Irrespective of the precise nature of this requirement, this study illustrates the importance of pathogen metabolism, and the regulation thereof, as a virulence factor.IMPORTANCEVibrio choleraecontinues to be a severe cause of morbidity and mortality in developing countries. Identification ofV. choleraefactors critical to disease progression offers the potential to develop or improve upon therapeutics and prevention strategies. To increase the efficiency of virulence factor discovery, we employed a regulator-centric approach to multiplex our in vivo screening capabilities and allow whole regulons inV. choleraeto be interrogated for pathogenic potential. We identified MetR as a new virulence regulator and serine hydroxymethyltransferase GlyA1 as a new MetR-regulated virulence factor, both required byV. choleraeto colonize the infant mouse intestine. Bacterial metabolism is a prerequisite to virulence, and current knowledge of in vivo metabolism of pathogens is limited. Here, we expand the known role of amino acid metabolism and regulation in virulence and offer new insights into the in vivo metabolic requirements ofV. choleraewithin the mouse intestine.

sae is essential for expression of the staphylococcal adhesins Eap and Emp

Microbiology ◽  
2005 ◽  
Vol 151 (6) ◽  
pp. 1789-1800 ◽  
Author(s):  
Niamh Harraghy ◽  
Jan Kormanec ◽  
Christiane Wolz ◽  
Dagmar Homerova ◽  
Christiane Goerke ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Extracellular Matrix ◽  
Virulence Factor ◽  
Eukaryotic Cells ◽  
Transcription Start Point ◽  
Chronic Infections ◽  
Transcription Start ◽  
Regulatory Mutants ◽  
Global Regulators ◽  
Glucose Analysis

Eap and Emp are two Staphylococcus aureus adhesins initially described as extracellular matrix binding proteins. Eap has since emerged as being important in adherence to and invasion of eukaryotic cells, as well as being described as an immunomodulator and virulence factor in chronic infections. This paper describes the mapping of the transcription start point of the eap and emp promoters. Moreover, using reporter-gene assays and real-time PCR in defined regulatory mutants, environmental conditions and global regulators affecting expression of eap and emp were investigated. Marked differences were found in expression of eap and emp between strain Newman and the 8325 derivatives SH1000 and 8325-4. Moreover, both genes were repressed in the presence of glucose. Analysis of expression of both genes in various regulatory mutants revealed that sarA and agr were involved in their regulation, but the data suggested that there were additional regulators of both genes. In a sae mutant, expression of both genes was severely repressed. sae expression was also reduced in the presence of glucose, suggesting that repression of eap and emp in glucose-containing medium may, in part, be a consequence of a decrease in expression of sae.

scholarly journals Antimicrobial Use, Residues, Resistance and Governance in the Food and Agriculture Sectors, Tanzania

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 454
Author(s):  
Robinson H. Mdegela ◽  
Elibariki R. Mwakapeje ◽  
Bachana Rubegwa ◽  
Daniel T. Gebeyehu ◽  
Solange Niyigena ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Resistance ◽  
Crop Production ◽  
Growth Promotion ◽  
Penicillin G ◽  
Animal Origin ◽  
Antimicrobial Use ◽  
Food And Agriculture ◽  
Food Of Animal Origin ◽  
Food Animals

All infections are potentially curable as long as the etiological agents are susceptible to antimicrobials. The increased rate at which antimicrobials are becoming ineffective is a global health risk of increasing concern that threatens withdrawal of beneficial antimicrobials for disease control. The increased demand for food of animal origin, in particular eggs, meat and milk has led to intensification and commercial production systems where excessive use and misuse of antimicrobials may prevail. Antimicrobials, handled and used by farmers and animal attendants with no formal education, may be predisposed to incorrect dosages, misuse, incorrect applications and non-adherence to withdrawal periods. This study was conducted to assess the regulatory roles and governance of antimicrobials, establish the pattern and extent of their use, evaluate the antimicrobial residues and resistance in the food animals and crop agriculture value chains, and relate these findings to existing strategies in place for combating the emergence of antimicrobial resistance in Tanzania. A multimethod approach (desk review, field study and interviews) was used. Relevant establishments were also visited. High levels of resistance to penicillin G, chloramphenicol, streptomycin and oxytetracycline have been reported, especially for Actinobacter pyogenes, Staphylococcus hyicus, Staphylococcus intermedius and Staphylococcus aureus from dairy cattle with mastitis and in humans. Similar trends were found in poultry where eggs and meat are contaminated with Escherichia coli strains resistant to amoxicillin + clavulanate, sulphamethoxazole and neomycin. An increasing trend of emerging multidrug resistant E. coli, Klebsiella pneumoniae, Staphylococcus aureus and Salmonella was also found in food animals. An increase in methicillin resistant Staphlococcus aureus (MRSA) and extended-spectrum beta-lactamase (ESBL) in the livestock sector in Tanzania have been reported. The pathogens isolated in animals were resistant to ampicillin, augmentin, gentamicin, co-trimoxazole, tetracycline, amoxicillin, streptomycin, nalidixic acid, azithromycin, chloramphenicol, tylosin, erythromycin, cefuroxime, norfloxacin and ciprofloxacin. An increased usage of antimicrobials for prophylaxis, and therapeutics against pathogens and for growth promotion in livestock, aquaculture and crop production were observed. A One Health strategic approach is advocated to combat antimicrobial resistance (AMR) in the food and agriculture sectors in Tanzania. Practical recommendations include (a) legislation review and implementation; (b) antimicrobial use (AMU), AMR and antimicrobial residue (AR) awareness and advocacy among stakeholders along the value chain; (c) strengthening of surveillance and monitoring programs for AMU, AMR and AR; (d) enhanced development and use of rapid and innovative diagnostic tests and the promotion of biosecurity principles; and (e) good husbandry practices. The utilization of this information to improve public health policies and reduce the burden of AMR will be beneficial.

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