RESUMEN

Staphylococcus aureus possesses sar family genes, including sarA, S, R, T, U, V, X, Y, Z, and rot, which are transcription factors involved in biofilm formation and quorum sensing. In contrast, Staphylococcus epidermidis has sarA, R, V, X, Y, Z, and rot genes; specifically, SarA, Z, and X are involved in biofilm formation. The expression of the sar family members in S. epidermidis isolated from clinical and non-clinical environments is unknown. This study aimed to establish if clinical and non-clinical isolates of S. epidermidis express the sar family members. We genotyped isolates from clinical ocular infections (n = 52), or non-clinical healthy conjunctiva (n = 40), and healthy skin (n = 50), using multilocus sequence typing (MLST) and the staphylococcal chromosomal cassette mec (SCCmec). We selected strains with different genotypes and representatives of each source of isolation, and the presence of the sar family genes was detected using PCR and RT-qPCR to determine their expression. The sar family genes were present in all selected strains, with no observed differences. The relative expression of the sar family showed that all selected strains expressed each gene weakly, with no significant differences observed between them or between different sources of isolation. In conclusion, the presence and relative expression of the sar family genes are very similar among strains, with no differences based on their origin of isolation and genotype. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01339-x.

RESUMEN

In addition to comprising monomers of nucleic acids, nucleotides have signaling functions and act as second messengers in both prokaryotic and eukaryotic cells. The most common example is cyclic AMP (cAMP). Nucleotide signaling is a focus of great interest in bacteria. Cyclic di-AMP (c-di-AMP), cAMP, and cyclic di-GMP (c-di-GMP) participate in biological events such as bacterial growth, biofilm formation, sporulation, cell differentiation, motility, and virulence. Moreover, the cyclic-di-nucleotides (c-di-nucleotides) produced in pathogenic intracellular bacteria can affect eukaryotic host cells to allow for infection. On the other hand, non-cyclic nucleotide molecules pppGpp and ppGpp are alarmones involved in regulating the bacterial response to nutritional stress; they are also considered second messengers. These second messengers can potentially be used as therapeutic agents because of their immunological functions on eukaryotic cells. In this review, the role of c-di-nucleotides and cAMP as second messengers in different bacterial processes is addressed.

Asunto(s)

GMP Cíclico , Sistemas de Mensajero Secundario , Sistemas de Mensajero Secundario/fisiología , Transducción de Señal/fisiología , Bacterias , AMP Cíclico , Nucleótidos Cíclicos , Proteínas Bacterianas

RESUMEN

Mesangial cells (MC) maintain the architecture and cellular communication and indirectly join in the glomerular filtration rate for the correct functioning of the glomerulus. Consequently, these cells are activated constantly in response to changes in the intraglomerular environment due to a metabolic imbalance or infection. IL-36, a member of the IL-1 family, is a cytokine that initiates and maintains inflammation in different tissues in acute and chronic pathologies, including the skin, lungs, and intestines. In the kidney, IL-36 has been described in the development of tubulointerstitial lesions, the production of an inflammatory environment, and is associated with metabolic and mesangioproliferative disorders. The participation of IL-36 in functional dysregulation and the consequent generation of the inflammatory environment by MCs in the presence of microbial stimulation is not yet elucidated. In this work, the MES SV40 cell cultures were stimulated with classical pathogen-associated molecular patterns (PAMPs), mimicking an infection by negative and positive bacteria as well as a viral infection. Lipopolysaccharide (LPS), peptidoglycan (PGN) microbial wall components, and a viral mimic poly I:C were used, and the mRNA and protein expression of the IL-36 members were assessed. We observed a differential and dose-dependent IL-36 mRNA and protein expression under LPS, PGN, and poly I:C stimulation. IL-36ß was only found when the cells were treated with LPS, while IL-36α and IL-36γ were favored by PGN and poly I:C stimulation. We suggest that the microbial components participate in the activation of MCs, leading them to the production of IL-36, in which a specific member may participate in the origin and maintenance of inflammation in the glomerular environment that is associated with infections.

Asunto(s)

Citocinas , Lipopolisacáridos , Citocinas/metabolismo , Humanos , Inflamación , Interleucina-1/genética , Interleucina-1/metabolismo , Lipopolisacáridos/farmacología , Moléculas de Patrón Molecular Asociado a Patógenos , Peptidoglicano/farmacología , Poli I-C , ARN Mensajero/genética

RESUMEN

Neutrophils play a crucial role in eliminating bacteria that invade the human body; however, cathepsin G can induce biofilm formation in a non-biofilm-forming Staphylococcus epidermidis 1457 strain, suggesting that neutrophil proteases may be involved in biofilm formation. Cathepsin G, cathepsin B, proteinase-3, and metalloproteinase-9 (MMP-9) from neutrophils were tested on the biofilm induction in commensal (skin isolated) and clinical non-biofilm-forming S. epidermidis isolates. From 81 isolates, 53 (74%) were aap+, icaA−, icaD− genotype, and without the capacity of biofilm formation under conditions of 1% glucose, 4% ethanol or 4% NaCl, but these 53 non-biofilm-forming isolates induced biofilm by the use of different neutrophil proteases. Of these, 62.3% induced biofilm with proteinase-3, 15% with cathepsin G, 10% with cathepsin B and 5% with MMP -9, where most of the protease-induced biofilm isolates were commensal strains (skin). In the biofilm formation kinetics analysis, the addition of phenylmethylsulfonyl fluoride (PMSF; a proteinase-3 inhibitor) showed that proteinase-3 participates in the cell aggregation stage of biofilm formation. A biofilm induced with proteinase-3 and DNAse-treated significantly reduced biofilm formation at an early time (initial adhesion stage of biofilm formation) compared to untreated proteinase-3-induced biofilm (p < 0.05). A catheter inoculated with a commensal (skin) non-biofilm-forming S. epidermidis isolate treated with proteinase-3 and another one without the enzyme were inserted into the back of a mouse. After 7 days of incubation period, the catheters were recovered and the number of grown bacteria was quantified, finding a higher amount of adhered proteinase-3-treated bacteria in the catheter than non-proteinase-3-treated bacteria (p < 0.05). Commensal non-biofilm-forming S. epidermidis in the presence of neutrophil cells significantly induced the biofilm formation when multiplicity of infection (MOI) 1:0.01 (neutrophil:bacteria) was used, but the addition of a cocktail of protease inhibitors impeded biofilm formation. A neutrophil:bacteria assay did not induce neutrophil extracellular traps (NETs). Our results suggest that neutrophils, in the presence of commensal non-biofilm-forming S. epidermidis, do not generate NETs formation. The effect of neutrophils is the production of proteases, and proteinase-3 releases bacterial DNA at the initial adhesion, favoring cell aggregation and subsequently leading to biofilm formation.

Asunto(s)

Neutrófilos , Péptido Hidrolasas , Infecciones Estafilocócicas , Staphylococcus epidermidis , Animales , Biopelículas , Catepsina B , Catepsina G , Metaloproteasas , Ratones , Mieloblastina , Neutrófilos/metabolismo , Péptido Hidrolasas/metabolismo , Infecciones Estafilocócicas/microbiología

RESUMEN

The Staphylococcus aureus SdrG protein is glycosylated by SdgA and SdgB for protection against its degradation by the neutrophil cathepsin G. So far, there is no information about the role of Staphylococcus epidermidis SdgA or SdgB in biofilm-forming; therefore, the focus of this work was to determine the distribution and expression of the sdrG, sdgA and sdgB genes in S. epidermidis under in vitro and in vivo biofilm conditions. The frequencies of the sdrG, sdgA and sdgB genes were evaluated by PCR in a collection of 75 isolates. Isolates were grown in dynamic (non-biofilm-forming) or static (biofilm-forming) conditions. The expression of sdrG, sdgA and sdgB was determined by RT-qPCR in cells grown under dynamic conditions (CGDC), as well as in planktonic and sessile cells from a biofilm and cells adhered to a catheter implanted in Balb/c mice. The sdrG and sdgB genes were detected in 100% of isolates, while the sdgA gene was detected in 71% of the sample (p < 0.001). CGDC did not express sdrG, sdgA and sdgB mRNAs. Planktonic and sessile cells expressed sdrG and sdgB, and the same was observed in cells adhered to the catheter. In particular, one isolate, capable of inducing a biofilm under treatment with cathepsin G, expressed sdrG and sdgB in planktonic and sessile cells and cells adhering to the catheter. This suggests that bacteria require biofilm conditions as an important factor for the transcription of the sdgA, sdgB and sdrG genes.

Asunto(s)

Infecciones Estafilocócicas , Staphylococcus epidermidis , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas , Catepsina G , Glicosiltransferasas/genética , Ratones , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/metabolismo

RESUMEN

Staphylococcus epidermidis is more abundant in the anterior nares than internal parts of the nose, but its relative abundance changes along with age; it is more abundant in adolescents than in children and adults. Various studies have shown that S. epidermidis is the guardian of the nasal cavity because it prevents the colonization and infection of respiratory pathogens (bacteria and viruses) through the secretion of antimicrobial molecules and inhibitors of biofilm formation, occupying the space of the membrane mucosa and through the stimulation of the host's innate and adaptive immunity. There is a strong relationship between the low number of S. epidermidis in the nasal cavity and the increased risk of serious respiratory infections. The direct application of S. epidermidis into the nasal cavity could be an effective therapeutic strategy to prevent respiratory infections and to restore nasal cavity homeostasis. This review shows the mechanisms that S. epidermidis uses to eliminate respiratory pathogens from the nasal cavity, also S. epidermidis is proposed to be used as a probiotic to prevent the development of COVID-19 because S. epidermidis induces the production of interferon type I and III and decreases the expression of the entry receptors of SARS-CoV-2 (ACE2 and TMPRSS2) in the nasal epithelial cells.

RESUMEN

Extracellular vesicles (EVs) are evaginations of the cytoplasmic membrane, containing nucleic acids, proteins, lipids, enzymes, and toxins. EVs participate in various bacterial physiological processes. Staphylococcus epidermidis interacts and communicates with the host skin. S. epidermidis' EVs may have an essential role in this communication mechanism, modulating the immunological environment. This work aimed to evaluate if S. epidermidis' EVs can modulate cytokine production by keratinocytes in vitro and in vivo using the imiquimod-induced psoriasis murine model. S. epidermidis' EVs were obtained from a commensal strain (ATC12228EVs) and a clinical isolated strain (983EVs). EVs from both origins induced IL-6 expression in HaCaT keratinocyte cultures; nevertheless, 983EVs promoted a higher expression of the pro-inflammatory cytokines VEGF-A, LL37, IL-8, and IL-17F than ATCC12228EVs. Moreover, in vivo imiquimod-induced psoriatic skin treated with ATCC12228EVs reduced the characteristic psoriatic skin features, such as acanthosis and cellular infiltrate, as well as VEGF-A, IL-6, KC, IL-23, IL-17F, IL-36γ, and IL-36R expression in a more efficient manner than 983EVs; however, in contrast, Foxp3 expression did not significantly change, and IL-36 receptor antagonist (IL-36Ra) was found to be increased. Our findings showed a distinctive immunological profile induction that is dependent on the clinical or commensal EV origin in a mice model of skin-like psoriasis. Characteristically, proteomics analysis showed differences in the EVs protein content, dependent on origin of the isolated EVs. Specifically, in ATCC12228EVs, we found the proteins glutamate dehydrogenase, ornithine carbamoyltransferase, arginine deiminase, carbamate kinase, catalase, superoxide dismutase, phenol-soluble ß1/ß2 modulin, and polyglycerol phosphate α-glucosyltransferase, which could be involved in the reduction of lesions in the murine imiquimod-induced psoriasis skin. Our results show that the commensal ATCC12228EVs have a greater protective/attenuating effect on the murine imiquimod-induced psoriasis by inducing IL-36Ra expression in comparison with EVs from a clinical isolate of S. epidermidis.

Asunto(s)

Vesículas Extracelulares/metabolismo , Psoriasis/terapia , Staphylococcus epidermidis/metabolismo , Animales , Antígenos Ly/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Vesículas Extracelulares/química , Vesículas Extracelulares/trasplante , Humanos , Imiquimod/toxicidad , Interleucina-1/antagonistas & inhibidores , Interleucina-1/genética , Interleucina-1/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Ratones , Infiltración Neutrófila , Psoriasis/inducido químicamente , Psoriasis/patología , Piel/metabolismo , Piel/patología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo

RESUMEN

Previous studies have shown that biofilm-forming bacteria are deficient in tricarboxylic acid (TCA) cycle metabolites, suggesting a relationship between these cellular processes. In this work, we compared the proteomes of planktonic vs biofilm cells from a clinical strain of Staphylococcus epidermidis using LC-MS/MS. A total of 168 proteins were identified from both growth conditions. The biofilm cells showed enrichment of proteins participating in glycolysis for the formation of pyruvate; however, the absence of TCA cycle proteins and the presence of lactate dehydrogenase, formate acetyltransferase, and acetoin reductase suggested that pyruvate was catabolized to their respective products: lactate, formate and acetoin. On the other hand, planktonic cells showed proteins participating in glycolysis and the TCA cycle, the pentose phosphate pathway, gluconeogenesis, ATP generation and the oxidative stress response. Functional networks with higher interconnection were predicted for planktonic proteins. We propose that in S. epidermidis, the relative absence of TCA cycle proteins is associated with the formation of biofilms and that lactate, formate and acetoin are the end products of partial glucose metabolism.

Asunto(s)

Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas , Proteoma , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/metabolismo , Metabolismo de los Hidratos de Carbono , Cromatografía Liquida , Ciclo del Ácido Cítrico , ADN Bacteriano , Regulación Bacteriana de la Expresión Génica , Glucólisis , Humanos , Proteómica , Infecciones Estafilocócicas/microbiología , Espectrometría de Masas en Tándem

RESUMEN

During the progression of psoriatic lesions, abundant cellular infiltration of myeloid cells, such as macrophages and activated dendritic cells, occurs in the skin and the infiltrating cells interact with naive lymphoid cells to generate a T helper (Th)1 and Th17 environment. Therapies to treat psoriasis include phototherapy, non­steroidal and steroidal drugs, as well as antibodies to block tumor necrosis factor­α, interleukin (IL)­17­A and IL­12/IL­23, which all focus on decreasing the proinflammatory hallmark of psoriasis. The present study obtained the heptapeptide HP3 derived from phage display technology that blocks mononuclear cell adhesion to endothelial cells and inhibits trans­endothelial migration in vitro. The activity of the heptapeptide in a murine model of psoriasis was also assessed, which indicated that early administration inhibited the development of psoriatic lesions. Therefore, the results suggested that HP3 may serve as a potential therapeutic target for psoriasis.

Asunto(s)

Células Endoteliales/efectos de los fármacos , Leucocitos Mononucleares/efectos de los fármacos , Oligopéptidos/uso terapéutico , Psoriasis/tratamiento farmacológico , Migración Transendotelial y Transepitelial/efectos de los fármacos , Animales , Línea Celular , Modelos Animales de Enfermedad , Células Endoteliales/citología , Células Endoteliales/patología , Femenino , Humanos , Imiquimod , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/patología , Ratones , Ratones Endogámicos BALB C , Oligopéptidos/química , Oligopéptidos/farmacología , Psoriasis/inducido químicamente , Psoriasis/patología

RESUMEN

In the original publication of the article, the authorship was published incorrectly.

RESUMEN

Currently, the treatment of infections by Staphylococcus epidermidis (S. epidermidis) represents a challenge because some strains have multidrug-resistance to antimicrobial products (antibiotic and biocides) and can produce biofilms. These biofilms protect bacterial cells from both antimicrobials and the host immune response. Therefore, it is crucial to encourage research on the development of new treatments. One method is immunotherapy, targeting components of S. epidermidis, such as S. epidermidis surface (Ses) proteins. Ses is expressed constitutively in most strains, and they participate in biofilm formation. This review is an update on Ses, regarding their structure, biological function, their relationship with S. epidermidis biofilm formation, and its possible role as therapeutic targets to develop immunotherapeutic treatments to prevent infections by S. epidermidis.

Asunto(s)

Antibacterianos , Proteínas Bacterianas , Biopelículas/efectos de los fármacos , Pared Celular , Staphylococcus epidermidis , Descubrimiento de Drogas , Humanos , Inmunoterapia , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/química , Staphylococcus epidermidis/citología , Staphylococcus epidermidis/efectos de los fármacos

RESUMEN

Staphylococcus epidermidis is a coagulase-negative bacterium capable of causing recurrent relapses in prosthetic joint infection (PJI). The aim of this study was to determine if Staphylococcus epidermidis isolates from patients with recurrent relapses of prosthetic joint infection (PJI) changed genotypically (pulsed-field gel electrophoresis (PFGE) pattern analysis and genes involved in biofilm formation) and phenotypically (antimicrobial resistance, biofilm formation) during the different episodes. Four patients with PJI recurrent relapses were evaluated clinically and microbiologically. Genotypic and phenotypic characteristics of 31 S. epidermidis isolates were determined. In all cases, PJI was treated with antimicrobial therapy and resection of the prosthesis without reimplantation. Months later, all patients had a relapse episode and treated with rifampin plus vancomycin and surgical debridement. Changes in the antibiotics resistance profile in isolates from patients 1 and 2 were observed in the two episodes. Patient 1 had four clones A, B, C, and D that were distributed differentially in the two episodes. Similarly, patients 2 and 3 had two clones and subclones (E-E1 and F-F1, respectively), and patient 4 had only the clone G in both episodes. The clone F formed small-colony variants (SCVs). High level of biofilm formation was found in all clones, except for clones D and G. Clones/subclones showed a genotypic variation in icaA, sdrF, bap, sesI, and embp genes. The principal coordinate analysis showed that all clones/subclones were different. These results showed that the initial infective clone of S. epidermidis from PJI, changed genotypically and phenotypically after a second relapse as a response to the treatment.

Asunto(s)

Prótesis Articulares/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Staphylococcus epidermidis/genética , Adulto , Anciano , Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Estudios Transversales , Farmacorresistencia Bacteriana Múltiple , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Fenotipo , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Recurrencia , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/clasificación , Staphylococcus epidermidis/efectos de los fármacos , Factores de Virulencia/genética

RESUMEN

Brucellosis, also known as "undulant fever" is a zoonotic disease caused by Brucella, which is a facultative intracellular bacterium. Despite efforts to eradicate this disease, infection in uncontrolled domestic animals persists in several countries and therefore transmission to humans is common. Brucella evasion of the innate immune system depends on its ability to evade the mechanisms of intracellular death in phagocytic cells. The BvrR-BvrS two-component system allows the bacterium to detect adverse conditions in the environment. The BvrS protein has been associated with genes of virulence factors, metabolism, and membrane transport. In this study, we predicted the DNA sequence recognized by BvrR with Gibbs Recursive Sampling and identified the three-dimensional structure of BvrR using I-TASSER suite, and the interaction mechanism between BvrR and DNA with Protein-DNA docking and molecular dynamics (MD) simulation. Based on the Gibbs recursive Sampling analysis, we found the motif AAHTGC (H represents A, C, and T nucleotides) as a possible sequence recognized by BvrR. The docking and EMD simulation results showed that C-terminal effector domain of BvrR protein is likely to interact with AAHTGC sequence. In conclusion, we predicted the structure, recognition motif, and interaction of BvrR with DNA.

Asunto(s)

Proteínas Bacterianas/química , Brucella/química , ADN/química , Factores de Virulencia/química , Secuencias de Aminoácidos , Proteínas Bacterianas/metabolismo , Sitios de Unión , Brucella/patogenicidad , ADN/metabolismo , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Motivos de Nucleótidos , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Homología Estructural de Proteína , Termodinámica , Factores de Virulencia/metabolismo

RESUMEN

The three-component apsXRS system senses and responds to cationic antimicrobial peptides (CAMPs), which induces the expression of the dlt operon and the genes mprF and vrafG, modifying the surface net charge in Staphylococcus epidermidis, resulting in the repulsion of CAMPs. The apsXRS system has been only studied in the S. epidermidis 1457 strain, and there are no studies of prevalence and level of expression of apsXRS in commensal and clinical isolates. From 60 isolates, those selected from commensal healthy skin (n = 20), commensal healthy conjunctive (n = 10), and clinical ocular infection (n = 30) presented the apsX, apsR, and apsS genes in their genomes. Constitutive expression of apsX, apsR, and apsS genes was determined by RT-qPCR in all isolates. It was found that expression of apsX, apsR, and apsS was 3.3-5.9-fold higher in commensal isolates stimulated with LL-37 (15 µg/mL) than in clinical isolates. Similarly, expression of the dlt operon and the genes mprF, and vraFG was 8-10-fold higher in commensal isolates than in clinical. However, LL-37 did not increase the addition of lysine in the phospholipids of the cytoplasmic membrane in any of the isolates. Mutations in the apsS loop region, apsR, and their promoter sequence were not found. These results demonstrated that apsXRS system is essential in all isolates for its constitutive expression; however, LL-37 caused an increase of apsXRS expression in commensal isolates, suggesting that S. epidermidis isolates do not respond in the same way to the presence of LL-37.

RESUMEN

Epidemiological studies comparing clinical and commensal Staphylococcus epidermidis isolates suggest that biofilm formation is a discriminant biomarker. A study showed that four non-biofilm-forming clinical S. epidermidis isolates could form an induced biofilm by trypsin treatment, suggesting that S. epidermidis can form biofilms in a protease-independent way and in a trypsin-induced way. In this study, the trypsin capacity to induce biofilm formation was evaluated in non-biofilm-forming S. epidermidis isolates (n = 133) in order to support this mechanism and to establish the importance of total biofilms (meaning the sum of protease-independent biofilm and trypsin-induced biofilm). Staphylococcus epidermidis isolates from ocular infections (OI; n = 24), prosthetic joint infections (PJI; n = 64), and healthy skin (HS-1; n = 100) were screened for protease-independent biofilm formation according to Christensen's method. The result was that there are significant differences (p < .0001) between clinical (43.2%) and commensal (17%) protease-independent biofilm producers. Meanwhile, non-biofilm-forming isolates were treated with trypsin, and biofilm formation was evaluated by the same method. The number of commensal trypsin-induced biofilm producers significantly increased from 17% to 79%. In contrast, clinical isolates increased from 43.2% to 72.7%. The comparison between clinical and commensal total biofilm yielded no significant differences (p = .392). A similar result was found when different isolation sources were compared (OI vs. HS-1 and PJI vs. HS-1). The genotype icaA- /aap+ was associated with the trypsin-induced biofilm phenotype; however, no correlation was observed between aap mRNA expression and the level of trypsin-induced biofilm phenotype. Studying another group of commensal S. epidermidis non-biofilm-forming isolates (HS-2; n = 139) from different body sites, it was found that 70 isolates (60.3%) formed trypsin-induced biofilms. In conclusion, trypsin is capable of inducing biofilm production in non-biofilm-forming commensal S. epidermidis isolates with the icaA- /aap+ genotype, and there is no significant difference in total biofilms when comparing clinical and commensal isolates, suggesting that total biofilms are not a discriminant biomarker.

Asunto(s)

Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/crecimiento & desarrollo , Tripsina/metabolismo , Proteínas Bacterianas/genética , Oftalmopatías/microbiología , Perfilación de la Expresión Génica , Genotipo , Voluntarios Sanos , Humanos , Osteoartritis/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Piel/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/aislamiento & purificación

RESUMEN

Objective: To determine the prevalence and virulence factors of coagulase-negative Staphylococci (CNS) in prosthetic joint infections (PJI). Method: CNS were isolated of 66 hip and knee PJI from Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, México City. Antimicrobial susceptibility and biofilm formation in CNS were determined; icaADBC, aap, bap and embp genes were determined by PCR. Results: Staphylococcus and Staphylococcus hominis were the most prevalent with 82 y 80% respectively. Staphylococcus lugdunensis, Staphylococcus haemolyticus, Staphylococcus capitis, Staphylococcus caprae, Staphylococcus sciuri and Staphylococcus lentus were less frequent. The majority of isolates were resistant to ß-lactam antibiotics, fluoroquinolone, and erythromycin. 41% of CNS were biofilm former and 59% were non-biofilm former (p = 0.0551). Biofilm former Staphylococcus epidermidis showed a high presence of icaADBC, aap and embp operons compared to the non-biofilm former isolates (p < 0.05). In contrast, non-S. epidermidis CNS had only the aap gen. Conclusion: S. haemolyticus, S. sciuri and S. lentus are new isolates of PJI not previously reported with virulence factors similar to CNS isolates.

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Objetivo: Estudiar la prevalencia y los factores de virulencia de Staphylococcus coagulasa negativos (SCN) de infecciones de prótesis articular (IPA). Método: Los SCN se aislaron de 66 pacientes con IPA de cadera y rodilla procedentes del Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, de Ciudad de México. Se determinaron la sensibilidad antimicrobiana y la producción de biopelículas de los SCN. Los genes icaADBC, aap, bap y embp fueron detectados por reacción en cadena de la polimerasa en SCN. Resultados: La IPA de cadera fue el 80%. Se aislaron en alta proporción S. epidermidis (82%) y S. hominis (80%), y en baja frecuencia S. lugdunensis, S. haemolyticus, S. capitis, S. caprae, S. sciuri y S. lentus. La mayoría de los aislamientos fueron resistentes a los betalactámicos, las fluoroquinolonas y la eritromicina. La producción de biopelículas se determinó en el 41% de los SCN y el 59% fueron no productores de biopelículas (p = 0.0551). S. epidermidis productores de biopelículas tuvieron mayor presencia del operón icaADBC, aap y embp que los aislamientos no productores de biopelícula (p < 0.05). Los SCN no S. epidermidis presentaron únicamente el gen aap. Conclusiones: S. haemolyticus, S. sciuri y S. lentus son aislamientos nuevos de IPA no reportados que poseen factores de virulencia, igual que las otras especies de SCN aisladas.

Asunto(s)

Biopelículas/crecimiento & desarrollo , Prótesis de la Rodilla/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Staphylococcus/aislamiento & purificación , Factores de Virulencia/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Bacterianas/genética , Coagulasa , Farmacorresistencia Bacteriana Múltiple/genética , Femenino , Genes Bacterianos , Prótesis de Cadera/microbiología , Prótesis de Cadera/estadística & datos numéricos , Hospitales Especializados , Humanos , Masculino , México , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Ortopedia , Estudios Retrospectivos , Staphylococcus/clasificación , Staphylococcus/enzimología , Staphylococcus/fisiología , Adulto Joven

RESUMEN

OBJECTIVES: Staphylococcus epidermidis can cause prosthetic joint infections. Strategies to differentiate between healthy skin and prosthetic joint infections isolates are relatively ineffective, which makes necessary to search for new differential biomarkers. Staphylococcus epidermidis has eleven surface proteins, denoted as Ses proteins. In this work, ses genes are used as biomarkers to differentiate between prosthetic joint infections and healthy skin isolates. METHODS: All prosthetic joint infections (n = 51) and healthy skin (n = 51) isolates were genotyped by pulsed-field gel electrophoresis. icaA, embp, sesA-I, and sdrF genes were determined by PCR. The phenotypic data included biofilm production and antibiotic resistance. RESULTS: 10 pulsed-field gel electrophoresis profiles were identified: four profiles were exclusive of prosthetic joint infections isolates, three profiles presented a higher proportion in prosthetic joint infections isolates and three profiles presented a higher proportion in healthy skin isolates. sesA, sesB, sesC, sesD, sesE, sesG, and sesH genes were more prevalent in healthy skin isolates than in prosthetic joint infections isolates (p < .05). Prosthetic joint infections isolates were more resistant to oxacillin (78%), ciprofloxacin (60%), levofloxacin (60%), and moxifloxacin (57%). The principal coordinate analysis and a discriminant analysis found that prosthetic joint infections isolates had as discriminant biomarker the biofilm formation, the icaA gene, oxacillin, ciprofloxacin, levofloxacin, moxifloxacin, and gentamicin resistance. In contrast, the healthy skin isolates had as discriminant biomarkers the embp, sesA, sesB, sesC, sesD, sesE, sesG, and sesH genes. CONCLUSIONS: These data suggest that ses genes can be considered biomarkers to differentiate between S. epidermidis commensal and prosthetic joint infections clinical.

Asunto(s)

Genes Bacterianos , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/genética , Simbiosis , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Artritis Infecciosa/microbiología , Biopelículas/crecimiento & desarrollo , Biomarcadores/análisis , Femenino , Marcadores Genéticos , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Piel/microbiología , Staphylococcus epidermidis/patogenicidad , Adulto Joven

RESUMEN

Staphylococci have quorum-sensing (QS) systems that enable cell-to-cell communication, as well as the regulation of numerous colonization and virulence factors. The accessory gene regulator (Agr) operon is one of the Staphylococcus genus QS systems. Three groups (I, II, and III) are present in Staphylococcus epidermidis Agr operon. To date, it is unknown whether Agr groups can interact symbiotically during biofilm development. This study analyzed a symbiotic association among Agr groups during biofilm formation in clinical and commensal isolates. Different combinations among Agr group isolates was used to study biofilm formation in vitro and in vivo (using a mouse catheter-infection model). The analysis of Agr groups were also performed from samples of human skin (head, armpits, and nostrils). Different predominant coexistence was found within biofilms, suggesting symbiosis type. In vitro, Agr I had a competition with Agr II and Agr III. Agr II had a competition with Agr III, and Agr II was an antagonist to Agr I and III when the three strains were combined. In vivo, Agr II had a competition to Agr I, but Agr I and II were antagonists to Agr III. The associations found in vitro and in vivo were also found in different sites of the skin. Besides, other associations were observed: Agr III antagonized Agr I and II, and Agr III competed with Agr I and Agr II. These results suggest that, in S. epidermidis, a symbiotic association of competition and antagonism occurs among different Agr groups during biofilm formation.

Asunto(s)

Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica/genética , Genes Bacterianos/genética , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/fisiología , Transactivadores/clasificación , Transactivadores/genética , Animales , Infecciones Relacionadas con Catéteres/microbiología , ADN Bacteriano/genética , Modelos Animales de Enfermedad , Femenino , Genotipo , Humanos , Ratones , Ratones Endogámicos BALB C , Tipificación de Secuencias Multilocus , Operón , Percepción de Quorum , Piel/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación

RESUMEN

Staphylococci produce a large number of extracellular proteases, some of which are considered as potential virulence factors. Staphylococcus epidermidis is a causative agent of nosocomial infections in medical devices by the formation of biofilms. It has been proposed that proteases contribute to the different stages of biofilm formation. S. epidermidis secretes a small number of extracellular proteases, such as serine protease Esp, cysteine protease EcpA, and metalloprotease SepA that have a relatively low substrate specificity. Recent findings indicate a significant contribution of extracellular proteases in biofilm formation through the proteolytic inactivation of adhesion molecules. The objective of this work is to provide an overview of the current knowledge of S. epidermidis' extracellular proteases during pathogenicity, especially in the different stages of biofilm formation.

Asunto(s)

Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Proteasas de Cisteína/metabolismo , Metaloendopeptidasas/metabolismo , Serina Proteasas/metabolismo , Staphylococcus epidermidis/enzimología , Moléculas de Adhesión Celular/metabolismo , Infección Hospitalaria/microbiología , Infección Hospitalaria/patología , Humanos , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología , Staphylococcus epidermidis/metabolismo , Staphylococcus epidermidis/patogenicidad , Factores de Virulencia/metabolismo

RESUMEN

PURPOSE: Staphylococcus epidermidis ATCC12228 lipoteichoic acid (LTA) inhibits TNFα production from keratinocytes that are activated with poly I:C. However, this effect has not been proven in clinical or commensal isolates. METHODOLOGY: The <10 kDa fractions of S. epidermidis isolates from ocular infections (n=56), healthy skin (n=35) and healthy conjunctiva (n=32) were obtained. TNFα production was determined by elisa in HaCaT keratinocytes stimulated with poly I:C and with the <10 kDa fractions. LTA in the cytoplasmic membrane and in the <10 kDa fractions of the isolates was determined during bacterial growth by flow cytometry, Western blot and electrospray ionization mass spectrometry. The expression levels of ugtP, ltaA and ltaS were evaluated. RESULTS: Two populations of isolates were found: a population that inhibited TNFα production (TNFα-inhibitor isolates) and a population that did not inhibit it (TNFα non-inhibitor isolates). The cells from the TNFα-inhibitor isolates had less LTA in the cytoplasmic membrane compared to the cells from the TNFα non-inhibitor isolates (P<0.05). Similarly, LTA was detected in the supernatants of TNFα-inhibitor isolates, and it was absent in TNFα non-inhibitor isolates. High expression levels of the ugtP and ltaA genes in the 1850I (TNFα-inhibitor isolate) and 37HS (TNFα non-inhibitor isolate) isolates were found during bacterial growth. However, the ltaS gene had a low expression level (P<0.05) in the 37HS isolate. CONCLUSION: The TNFα-inhibitor isolates release LTA due to high expression of the LTA synthesis genes. By contrast, TNFα non-inhibitor isolates do not release LTA due to low expression level of the ltaS gene.

Asunto(s)

Exocitosis , Expresión Génica , Genes Bacterianos , Lipopolisacáridos/metabolismo , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/metabolismo , Ácidos Teicoicos/metabolismo , Western Blotting , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Perfilación de la Expresión Génica , Humanos , Queratinocitos/inmunología , Queratinocitos/microbiología , Espectrometría de Masas , Staphylococcus epidermidis/aislamiento & purificación , Factor de Necrosis Tumoral alfa/metabolismo