Nucleotide Substitution and Recombination at Orthologous Loci in Staphylococcus aureus

ABSTRACT The pattern of nucleotide substitution was examined at 2,129 orthologous loci among five genomes of Staphylococcus aureus, which included two sister pairs of closely related genomes (MW2/MSSA476 and Mu50/N315) and the more distantly related MRSA252. A total of 108 loci were unusual in lacking any synonymous differences among the five genomes; most of these were short genes encoding proteins highly conserved at the amino acid sequence level (including many ribosomal proteins) or unknown predicted genes. In contrast, 45 genes were identified that showed anomalously high divergence at synonymous sites. The latter genes were evidently introduced by homologous recombination from distantly related genomes, and in many cases, the pattern of nucleotide substitution made it possible to reconstruct the most probable recombination event involved. These recombination events introduced genes encoding proteins that differed in amino acid sequence and thus potentially in function. Several of the proteins are known or likely to be involved in pathogenesis (e.g., staphylocoagulase, exotoxin, Ser-Asp fibrinogen-binding bone sialoprotein-binding protein, fibrinogen and keratin-10 binding surface-anchored protein, fibrinogen-binding protein ClfA, and enterotoxin P). Therefore, the results support the hypothesis that exchange of homologous genes among S. aureus genomes can play a role in the evolution of pathogenesis in this species.

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Immunogenicity Analysis of Staphylococcus aureus Clumping Factor A Genetic Variants

Clinical and Vaccine Immunology ◽

10.1128/cvi.00275-13 ◽

2013 ◽

Vol 20 (8) ◽

pp. 1338-1340 ◽

Cited By ~ 3

Author(s):

Rebecca A. Brady ◽

Christopher P. Mocca ◽

Drusilla L. Burns

Keyword(s):

Amino Acids ◽

Staphylococcus Aureus ◽

Amino Acid ◽

Amino Acid Sequence ◽

Immune Responses ◽

Genetic Variants ◽

Vaccine Candidate ◽

Fibrinogen Binding ◽

Epitope Structure ◽

Variant Amino Acid

ABSTRACTThe staphylococcal adhesin clumping factor A (ClfA) has a variant amino acid sequence, generating the potential for alterations in epitope structure and immunogenicity of this vaccine candidate. We demonstrated for two recombinant ClfA40–531(a slightly truncated version of the fibrinogen-binding domain of ClfA containing amino acids 40 to 531) genetic variants that strain-specific epitopes are immunodominant. This work indicates that immune responses elicited by ClfA may, at least in part, be dependent on the strain of origin of the ClfA.

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Effect of trans-Cinnamaldehyde on Methicillin-Resistant Staphylococcus aureus Biofilm Formation: Metabolic Activity Assessment and Analysis of the Biofilm-Associated Genes Expression

International Journal of Molecular Sciences ◽

10.3390/ijms21010102 ◽

2019 ◽

Vol 21 (1) ◽

pp. 102 ◽

Cited By ~ 4

Author(s):

Barbara Kot ◽

Hubert Sytykiewicz ◽

Iwona Sprawka ◽

Małgorzata Witeska

Keyword(s):

Staphylococcus Aureus ◽

Metabolic Activity ◽

Methicillin Resistant Staphylococcus Aureus ◽

Binding Protein ◽

Expression Level ◽

Biofilm Inhibition ◽

Methicillin Resistant ◽

Fibrinogen Binding ◽

Genes Encoding ◽

Laminin Binding Protein

The effects of trans-cinnamaldehyde (TC) on transcriptional profiles of biofilm-associated genes and the metabolic activity of two methicillin-resistant Staphylococcus aureus (MRSA) strains showing a different degree of adherence to polystyrene, were evaluated. Metabolic activity of S. aureus in biofilm was significantly decreased in the presence of TC at 1/2 minimum biofilm inhibition concentration (MBIC). Expression levels of the genes encoding laminin binding protein (eno), elastin binding protein (ebps) and fibrinogen binding protein (fib) in the presence of TC at 1/2 MBIC were lower than in untreated biofilm in both the weakly and strongly adhering strain. The highest decrease of expression level was observed in case of fib in the strongly adhering strain, in which the amount of fib transcript was 10-fold lower compared to biofilm without TC. In the presence of TC at 1/2 MBIC after 3, 6, 8 and 12 h, the expression level of icaA and icaD, that are involved in the biosynthesis of polysaccharide intercellular adhesin, was above half lower in the weakly adhering strain compared to biofilm without TC. In the strongly adhering strain the highest decrease in expression of these genes was observed after 3 and 6 h. This study showed that TC is a promising anti-biofilm agent for use in MRSA biofilm-related infections.

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Expression of the Biofilm-Associated Genes in Methicillin-Resistant Staphylococcus aureus in Biofilm and Planktonic Conditions

International Journal of Molecular Sciences ◽

10.3390/ijms19113487 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3487 ◽

Cited By ~ 12

Author(s):

Barbara Kot ◽

Hubert Sytykiewicz ◽

Iwona Sprawka

Keyword(s):

Staphylococcus Aureus ◽

Binding Protein ◽

Pcr Analysis ◽

Gene Encoding ◽

Methicillin Resistant ◽

Expression Levels ◽

Fibrinogen Binding ◽

Genes Encoding ◽

Laminin Binding Protein

The role of genes that are essential for development of Staphylococcus aureus biofilm during infection is not fully known. mRNA from two methicillin-resistant S. aureus strains that formed weak and strong biofilm on polystyrene plates were isolated at five time points from cells grown in biofilm and planktonic culture. Quantitative real-time PCR analysis showed that the expression levels of investigated genes under biofilm conditions were significantly higher than under planktonic conditions. The expression levels of the gene encoding elastin binding protein (ebps) and laminin binding protein (eno) were significantly increased in biofilm at 3 h, both in strongly and weakly adhering strain. The peak expression of fib gene encoding fibrinogen binding protein was found at 6 and 8 h in the case of strongly and weakly adhering strain, respectively. The expression of icaA and icaD genes in both strains was significantly higher under biofilm conditions when comparing to planktonic cells during 12 h. The expression level of the genes encoding binding proteins and the glucosamine polymer polysaccharide intercellular adhesin (PIA) slowly decreased after 24 h. Finally, we found that the expression levels of genes encoding binding factors in weakly adhering strain were significantly lower than in strongly adhering strain.

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Penicillin-Binding Protein 1 ofStaphylococcus aureus Is Essential for Growth

Journal of Bacteriology ◽

10.1128/jb.180.10.2759-2765.1998 ◽

1998 ◽

Vol 180 (10) ◽

pp. 2759-2765 ◽

Cited By ~ 29

Author(s):

Akihito Wada ◽

Haruo Watanabe

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Amino Acid ◽

Amino Acid Sequence ◽

Binding Protein ◽

Ofstaphylococcus Aureus ◽

Penicillin Binding Protein ◽

Gene Encoding ◽

Chromosomal Copy

ABSTRACT pbpA, a gene encoding penicillin-binding protein (PBP) 1 of Staphylococcus aureus, was cloned in anEscherichia coli MC1061 transformant which grew on a plate containing 512 μg of vancomycin per ml. This gene encodes a 744-amino-acid sequence which conserves three motifs of PBPs, SXXK, SXN, and KTG. The chromosomal copy of pbpA could be disrupted only when RN4220, a methicillin-sensitive S. aureus strain, had additional copies of pbpA in its episome. Furthermore, these episomal copies of pbpA could not be eliminated by an incompatible plasmid when the chromosomal copy of pbpA was disrupted beforehand. Based on these observations, we concluded that pbpA is essential for the growth of methicillin-sensitive S. aureus.

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Comparison of the Prevalence of Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) among Staphylococcus aureus Isolates in a Burn Unit with Non-Burning Units

Iranian Journal of Public Health ◽

10.18502/ijph.v50i1.5081 ◽

2021 ◽

Author(s):

Hossein SEDAGHAT ◽

Tahmineh NARIMANI ◽

Bahram NASR ESFAHANI ◽

Sina MOBASHERIZADEH ◽

Seyed Asghar HAVAEI

Keyword(s):

Staphylococcus Aureus ◽

Binding Protein ◽

Surface Proteins ◽

Clinical Samples ◽

Burn Center ◽

Fibrinogen Binding ◽

Burn Unit ◽

Genes Encoding ◽

Burn Units ◽

Laminin Binding Protein

Background: Staphylococcus aureus (S. aureus) is one of the most important pathogens in burn infections colonized in the nose and increase the risk of infections. Methods: Overall, 85 S. aureus isolates were isolated from clinical and nasal hospitalized patients and health care workers (HCWs) in a burn unit and non-burn units in Isfahan from June 2016 and September 2016. Genes encoding penicillin-binding protein 2a (mecA) and adhesive surface proteins, including fibronectin-binding proteins (fnbA, fnbB), fibrinogen binding protein (fib), laminin-binding protein(eno), collagen binding protein (cna), elastin binding protein (ebps), intracellular adhesion operon (icaA and icaD) were detected using PCR method. Results: The rate of methicillin-resistant S. aureus (MRSA) among burn and non-burn isolates were 62% (18/29) and 25% (14/56), respectively. The most prevalent MSCRAMMs genes in burn units were eno (86%) and fib (66%). The most common gene pattern in burn center was icaA+fib+eno. The frequency of icaD, fib and ebpS was higher in clinical samples than nasal samples. No relation was found between the MSCRAMMs genes in the burn unit and non-burn units. Conclusion: The high prevalence of MRSA in burn center can be a new challenge for clinicians. The higher frequency of icaD, fib and ebpS in clinical isolates than nasal isolates may reflect the important role of these genes in colonization and pathogenesis of S. aureus.

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The Fibrinogen- and Fibronectin-Binding Domains of Staphylococcus aureus Fibronectin-Binding Protein A Synergistically Promote Endothelial Invasion and Experimental Endocarditis

Infection and Immunity ◽

10.1128/iai.00405-08 ◽

2008 ◽

Vol 76 (8) ◽

pp. 3824-3831 ◽

Cited By ~ 63

Author(s):

Lionel Piroth ◽

Yok-Ai Que ◽

Eleonora Widmer ◽

Alexandre Panchaud ◽

Stéphane Piu ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Amino Acid ◽

Binding Protein ◽

Protein A ◽

Binding Domains ◽

Fibrinogen Binding ◽

Fibronectin Binding Protein ◽

Fibronectin Binding

ABSTRACT Staphylococcus aureus experimental endocarditis relies on sequential fibrinogen binding (for valve colonization) and fibronectin binding (for endothelial invasion) conferred by peptidoglycan-attached adhesins. Fibronectin-binding protein A (FnBPA) reconciles these two properties—as well as elastin binding—and promotes experimental endocarditis by itself. Here we attempted to delineate the minimal subdomain of FnBPA responsible for fibrinogen and fibronectin binding, cell invasion, and in vivo endocarditis. A large library of truncated constructs of FnBPA was expressed in Lactococcus lactis and tested in vitro and in animals. A 127-amino-acid subdomain spanning the hinge of the FnBPA fibrinogen-binding and fibronectin-binding regions appeared necessary and sufficient to confer the sum of these properties. Competition with synthetic peptides could not delineate specific fibrinogen- and fibronectin-binding sites, suggesting that dual binding arose from protein folding, irrespective of clearly defined binding domains. Moreover, coexpressing the 127-amino-acid subdomain with remote domains of FnBPA further increased fibrinogen binding by ≥10 times, confirming the importance of domain interactions for binding efficacy. In animals, fibrinogen binding (but not fibronectin binding) was significantly associated with endocarditis induction, whereas both fibrinogen binding and fibronectin binding were associated with disease severity. Moreover, fibrinogen binding also combined with fibronectin binding to synergize the invasion of cultured cell lines significantly, a feature correlating with endocarditis severity. Thus, while fibrinogen binding and fibronectin binding were believed to act sequentially in colonization and invasion, they appeared unexpectedly intertwined in terms of both functional anatomy and pathogenicity (in endocarditis). This unforeseen FnBPA subtlety might bear importance for the development of antiadhesin strategies.

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