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83 result(s) for "Staphylococcus capitis"
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A new approach for establishing multilocus sequence typing scheme: Staphylococcus capitis as an example
Reliable and efficient typing methods for Staphylococcus capitis , an opportunistic pathogen of growing clinical and epidemiological concern, are urgently needed to support microbial epidemiological studies. In the study, we present a novel workflow for developing a multilocus sequence typing (MLST) scheme tailored to S. capitis . Core genome analysis of 603 high-quality S. capitis genomes revealed 2,065 core genes. A hierarchical filtering strategy, including gene, fragment, and combination filters, was applied to select loci that balance discriminatory power and cluster specificity. The final MLST scheme comprised fragments from seven genes: mntC , phoA , atpB_2 , hisS , rluB , carB , and clpP . Using this approach, we assigned 39 sequence types (STs) and defined five clonal complexes. The MLST typing results were highly concordant with phylogenetic analysis and demonstrated considerable discriminatory power. Notably, the globally prevalent NRCS-A clone and the linezolid-resistant L clone were designated as ST1 and ST6, respectively. Overall, we developed a reliable, high-resolution MLST scheme for S. capitis that enables accurate characterization of its population structure and facilitates monitoring of multidrug-resistant lineages.
Recurrent bacteremia and endocarditis due to Staphylococcus capitis in a patient with Bowen’s disease: a case report
This case report details the management of a 79-year-old male with recurrent methicillin-resistant Staphylococcus capitis bacteremia and endocarditis. The patient’s clinical journey encompassed multiple hospital admissions, with challenges in managing endocarditis, pacemaker replacements, and potential cutaneous sources of infection. The treatment regimen included intravenous antibiotic therapy during hospitalization and suppressive antibiotic treatment upon discharge, alongside a decolonization strategy for his scalp lesions.
Neonatal infection with Staphylococcus capitis NRCS-A in Iceland: A 12-year longitudinal, retrospective study of strains from patients, staff and the environment in a neonatal intensive care unit
Background The multidrug resistant NRCS-A clone of Staphylococcus capitis (SC) has spread globally in neonatal intensive care units (NICUs) where it causes neonatal sepsis and colonisation of infants, fomites and staff. Whole genome sequencing (WGS) of international isolates has suggested a putative origin of the clone in Norway, which is closely related to Iceland geopolitically. No data have been available about the NRCS-A clone in Iceland where a case of neonatal sepsis in 2014 suggested its presence for the first time. This study examines the epidemiology of the clone in the single Icelandic NICU over a 12-year period and its relationship to international isolates. Methods The study involved retrospective examination of the occurrence and clinical significance of SC-NRCS-A isolated from blood cultures of infants during 2009 – 2020, and prospective screening for SC among infants, staff and the environment. WGS was done on selected isolates to verify the presence of the SC-NRCS-A clone, examine phylogenetic relationship within the Icelandic isolates, and compare them with an international collection of SC-NRCS-A. Results SC-NRCS-A was found in blood cultures from 28 infants, of which nine with sepsis, and was a frequent coloniser of infants and diverse fomites. In staff SC-NRCS-A was detected in nares, throat and scalp. WGS of 93 isolates from blood and prospective screening specimens and comparison with international isolates revealed that the Icelandic SC-NRCS-A was distributed into two clusters, one related to Norwegian and the other to Irish SC-NRCS-A isolates. Both clusters contained isolates representing all sample sources. Conclusion The study demonstrated interpatient transmission, widespread dissemination and persistence of the SC-NRCS-A clone in the Icelandic NICU. The close phylogenetic relationship of Icelandic isolates with those from Norway and Ireland suggests potential import to Iceland by NICU staff or infants receiving medical care in these neighbouring countries at some point before 2009 for the Irish clone and before 2014 for the Norwegian clone.
Genomic analysis of Staphylococcus capitis isolated from blood cultures in neonates at a neonatal intensive care unit in Sweden
Emergence of a genetically distinct, multidrug-resistant Staphylococcus capitis clone (NRCS-A) present in neonatal intensive care units has recently been extensively reported. The aims of the present study were to investigate which clones of S. capitis isolated from blood in a Swedish neonatal intensive care unit (NICU) have been present since 1987 and to investigate whether the NRCS-A clone has disseminated in Sweden. All S. capitis isolates from blood cultures of neonates (≤ 28 days of age) between 1987 and 2017 (n = 46) were whole-genome sequenced, and core genome multilocus sequence typing (cgMLST) was performed. Single-nucleotide polymorphism (SNP)-based phylogenetic relationships between the S. capitis isolates and in silico predictions of presence of genetic traits specific to the NRCS-A clone were identified. Furthermore, antibiotic susceptibility testing, including screening for heterogeneous glycopeptide-intermediate resistance, was performed. Thirty-five isolates clustered closely to the isolates previously determined as belonging to the NRCS-A clone and had fewer than 81 core genome loci differences out of 1063. Twenty-one of these isolates were multidrug resistant. The NRCS-A clone was found in 2001. Six pairs of isolates had differences of fewer than two SNPs. Genetic traits associated with the NRCS-A clone such as nsr, ebh, tarJ, and CRISPR were found in all 35 isolates. The increasing incidence of S. capitis blood cultures of neonates is predominantly represented by the NRSC-A clone at our NICU in Sweden. Furthermore, there were indications of transmission between cases; adherence to basic hygiene procedures and surveillance measures are thus warranted.
Complete genome sequencing of three human clinical isolates of Staphylococcus caprae reveals virulence factors similar to those of S. epidermidis and S. capitis
Background Staphylococcus caprae is an animal-associated bacterium regarded as part of goats’ microflora. Recently, S. caprae has been reported to cause human nosocomial infections such as bacteremia and bone and joint infections. However, the mechanisms responsible for the development of nosocomial infections remain largely unknown. Moreover, the complete genome sequence of S. caprae has not been determined. Results We determined the complete genome sequences of three methicillin-resistant S. caprae strains isolated from humans and compared these sequences with the genomes of S. epidermidis and S. capitis , both of which are closely related to S. caprae and are inhabitants of human skin capable of causing opportunistic infections. The genomes showed that S. caprae JMUB145, JMUB590, and JMUB898 strains contained circular chromosomes of 2,618,380, 2,629,173, and 2,598,513 bp, respectively. JMUB145 carried type V SCC mec , while JMUB590 and JMUB898 had type IVa SCC mec . A genome-wide phylogenetic SNP tree constructed using 83 complete genome sequences of 24 Staphylococcus species and 2  S. caprae draft genome sequences confirmed that S. caprae is most closely related to S. epidermidis and S. capitis . Comparative complete genome analysis of eight S. epidermidis , three S. capitis and three S. caprae strains revealed that they shared similar virulence factors represented by biofilm formation genes. These factors include wall teichoic acid synthesis genes, poly-gamma-DL-glutamic acid capsule synthesis genes, and other genes encoding nonproteinaceous adhesins. The 17 proteinases/adhesins and extracellular proteins known to be associated with biofilm formation in S. epidermidis were also conserved in these three species, and their biofilm formation could be detected in vitro. Moreover, two virulence-associated gene clusters, the type VII secretion system and capsular polysaccharide biosynthesis gene clusters, identified in S. aureus were present in S. caprae but not in S. epidermidis and S. capitis genomes. Conclusion The complete genome sequences of three methicillin-resistant S. caprae isolates from humans were determined for the first time. Comparative genome analysis revealed that S. caprae is closely related to S. epidermidis and S. capitis at the species level, especially in the ability to form biofilms, which may lead to increased virulence during the development of S. caprae infections.
Identification and characterisation of capidermicin, a novel bacteriocin produced by Staphylococcus capitis
One hundred human-derived coagulase negative staphylococci (CoNS) were screened for antimicrobial activity using agar-based deferred antagonism assays with a range of indicator bacteria. Based on the findings of the screen and subsequent well assays with cell free supernatants and whole cell extracts, one strain, designated CIT060, was selected for further investigation. It was identified as Staphylococcus capitis and herein we describe the purification and characterisation of the novel bacteriocin that the strain produces. This bacteriocin which we have named capidermicin was extracted from the cell-free supernatant of S. capitis CIT060 and purified to homogeneity using reversed-phase high performance liquid chromatography (RP-HPLC). Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometric (MS) analysis revealed that the capidermicin peptide has a mass of 5,464 Da. Minimal inhibitory concentration (MIC) experiments showed that capidermicin was active in the micro-molar range against all the Gram-positive bacteria that were tested. Antimicrobial activity was retained over a range of pHs (2-11) and temperatures (10-121°C x 15 mins). The draft genome sequence of S. capitis CIT060 was determined and the genes predicted to be involved in the biosynthesis of capidermicin were identified. These genes included the predicted capidermicin precursor gene, and genes that are predicted to encode a membrane transporter, an immunity protein and a transcriptional regulator. Homology searches suggest that capidermicin is a novel member of the family of class II leaderless bacteriocins.
Niche specialization and spread of Staphylococcus capitis involved in neonatal sepsis
The multidrug-resistant Staphylococcus capitis NRCS-A clone is responsible for sepsis in preterm infants in neonatal intensive care units (NICUs) worldwide. Here, to retrace the spread of this clone and to identify drivers of its specific success, we investigated a representative collection of 250 S. capitis isolates from adults and newborns. Bayesian analyses confirmed the spread of the NRCS-A clone and enabled us to date its emergence in the late 1960s and its expansion during the 1980s, coinciding with the establishment of NICUs and the increasing use of vancomycin in these units, respectively. This dynamic was accompanied by the acquisition of mutations in antimicrobial resistance- and bacteriocin-encoding genes. Furthermore, combined statistical tools and a genome-wide association study convergently point to vancomycin resistance as a major driver of NRCS-A success. We also identified another S. capitis subclade (alpha clade) that emerged independently, showing parallel evolution towards NICU specialization and non-susceptibility to vancomycin, indicating convergent evolution in NICU-associated pathogens. These findings illustrate how the broad use of antibiotics can repeatedly lead initially commensal drug-susceptible bacteria to evolve into multidrug-resistant clones that are able to successfully spread worldwide and become pathogenic for highly vulnerable patients. A comparison of the evolutionary history and geographical spread of the antimicrobial-resistant pathogen Staphylococcus capitis in neonatal intensive care units indicates that acquisition of antibiotic resistance and increased competitiveness have led to the success of the NRCS-A S. capitis clone.
Presence of the neonatal Staphylococcus capitis outbreak clone (NRCS-A) in prosthetic joint infections
Staphylococcus capitis is a coagulase-negative staphylococcus that has been described primarily as causing bloodstream infections in neonatal intensive care units (NICUs), but has also recently been described in prosthetic joint infections (PJIs). The multidrug-resistant S. capitis subsp. urealyticus clone NRCS-A, comprising three sublineages, is prevalent in NICUs across the world, but its impact on other patient groups such as those suffering from PJIs or among adults planned for arthroplasty is unknown. Genome sequencing and subsequent analysis were performed on a Swedish collection of PJI isolates (n = 21), nasal commensals from patients planned to undergo arthroplasty (n = 20), NICU blood isolates (n = 9), operating theatre air isolates (n = 4), and reference strains (n = 2), in conjunction with an international strain collection (n = 248). The NRCS-A Outbreak sublineage containing the composite type V SCC mec -SCC cad/ars/cop element was present in PJIs across three Swedish hospitals. However, it was not found among nasal carrier strains, where the less virulent S. capitis subsp. capitis was most prevalent. The presence of the NRCS-A Outbreak clone in adult patients with PJIs demonstrates that dissemination occurs beyond NICUs. As this clone has several properties which facilitate invasive infections in patients with medical implants or immunosuppression, such as biofilm forming ability and multidrug resistance including heterogeneous glycopeptide-intermediate susceptibility, further research is needed to understand the reservoirs and distribution of this hospital-associated pathogen.
Rosa spp. Extracts as a Factor That Limits the Growth of Staphylococcus spp. Bacteria, a Food Contaminant
Due to their richness of bioactive substances, rose hips are a valuable raw material for obtaining extracts with potential antimicrobial activity. The aim of the study was to determine the antagonistic potential of whole pseudo-fruit and flesh extracts of three Rosa sp. varieties against Staphylococcus spp. bacteria isolated as food contaminants. The biological material in this study consisted of seven strains of bacteria from the genus Staphylococcus. Two strains—Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis DSMZ 3270—were used as reference strains. The other five strains were food-derived isolates—S. epidermidis A5, S. xylosus M5, S. haemolyticus M6, S. capitis KR6, and S. warneri KR2A. The material was the pseudo-fruits of Rosa canina, Rosa pomifera Karpatia, and Rosa rugosa. The polyphenols were extracted from the fleshy part and the whole pseudo-fruit for all rose varieties. The tested preparations differed significantly in their polyphenol composition. The sum of polyphenols ranged from 28 862 to 35 358 mg/100 g of lyophilisate. The main groups of polyphenols found in the preparations were flavanols and ellagitannins. All of the tested extracts inhibited the growth of staphylococci at a concentration of 500 mg/mL. Rosa rugosa fruit extract showed the strongest antimicrobial properties among the studied extracts. For all the strains, the growth inhibition had a diameter of 20.3–29.0 mm. Moreover, six out of the seven tested strains showed the highest inhibition with the use of this extract. The MIC of rose extracts was in the range of 3.125–500 mg/mL and was strictly dependent on the bacterial species, the species of the rose, and the part of the fruit from which the extract was obtained. Correlations were assessed between the main groups of polyphenols in the extracts and their inhibition of bacterial growth. In the case of pseudo-fruit extracts, the inhibitory effect on bacterial growth positively correlated with the content of ellagitannins, and this effect was observed for almost all the tested strains. The results presented herein follow the current trend of minimising the use of chemical preservatives in food; from this point of view, rose extracts are very promising.
Complete genome assemblies and antibiograms of 22 Staphylococcus capitis isolates
Objective Staphylococcus capitis is part of the human microbiome and an opportunistic pathogen known to cause catheter-associated bacteraemia, prosthetic joint infections, skin and wound infections, among others. Detection of S. capitis in normally sterile body sites saw an increase over the last decade in England, where a multidrug-resistant clone, NRCS-A, was widely identified in blood samples from infants in neonatal intensive care units. To address a lack of complete genomes and antibiograms of S. capitis in public databases, we performed long- and short-read whole-genome sequencing, hybrid genome assembly, and antimicrobial susceptibility testing of 22 diverse isolates. Data description We present complete genome assemblies of two S. capitis type strains (subspecies capitis : DSM 20326; subspecies urealyticus : DSM 6717) and 20 clinical isolates (NRCS-A: 10) from England. Each genome is accompanied by minimum inhibitory concentrations of 13 antimicrobials including vancomycin, teicoplanin, daptomycin, linezolid, and clindamycin. These 22 genomes were 2.4–2.7 Mbp in length and had a GC content of 33%. Plasmids were identified in 20 isolates. Resistance to teicoplanin, daptomycin, gentamicin, fusidic acid, rifampicin, ciprofloxacin, clindamycin, and erythromycin was seen in 1–10 isolates. Our data are a resource for future studies on genomics, evolution, and antimicrobial resistance of S. capitis .