To Örebro University

oru.seÖrebro University Publications
Change search
Link to record
Permanent link

Direct link
Hellmark, Bengt
Alternative names
Publications (10 of 31) Show all publications
Bengtsson, T., Selegård, R., Musa, A., Hultenby, K., Utterström, J., Sivlér, P., . . . Khalaf, H. (2020). Author Correction: Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Scientific Reports, 10(1), Article ID 16027.
Open this publication in new window or tab >>Author Correction: Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics
Show others...
2020 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 16027Article in journal (Refereed) Published
Abstract [en]

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Place, publisher, year, edition, pages
Nature Publishing Group, 2020
National Category
Cardiac and Cardiovascular Systems
Identifiers
urn:nbn:se:oru:diva-86049 (URN)10.1038/s41598-020-72918-3 (DOI)000615373300001 ()32973307 (PubMedID)2-s2.0-85091429718 (Scopus ID)
Note

Erratum for Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Bengtsson T, Selegård R, Musa A, Hultenby K, Utterström J, Sivlér P, Skog M, Nayeri F, Hellmark B, Söderquist B, Aili D, Khalaf H. Sci Rep. 2020 Feb 27;10(1):3580. doi: 10.1038/s41598-020-60570-w.

Available from: 2020-09-29 Created: 2020-09-29 Last updated: 2024-01-02Bibliographically approved
Bengtsson, T., Selegård, R., Musa, A., Hultenby, K., Utterström, J., Sivlér, P., . . . Khalaf, H. (2020). Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Scientific Reports, 10(1), Article ID 3580.
Open this publication in new window or tab >>Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics
Show others...
2020 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 3580Article in journal (Refereed) Published
Abstract [en]

The use of conventional antibiotics has substantial clinical efficacy, however these vital antimicrobial agents are becoming less effective due to the dramatic increase in antibiotic-resistant bacteria. Novel approaches to combat bacterial infections are urgently needed and bacteriocins represent a promising alternative. In this study, the activities of the two-peptide bacteriocin PLNC8 αβ were investigated against different Staphylococcus spp. The peptide sequences of PLNC8 α and β were modified, either through truncation or replacement of all L-amino acids with D-amino acids. Both L- and D-PLNC8 αβ caused rapid disruption of lipid membrane integrity and were effective against both susceptible and antibiotic resistant strains. The D-enantiomer was stable against proteolytic degradation by trypsin compared to the L-enantiomer. Of the truncated peptides, β1-22, β7-34 and β1-20 retained an inhibitory activity. The peptides diffused rapidly (2 min) through the bacterial cell wall and permeabilized the cell membrane, causing swelling with a disorganized peptidoglycan layer. Interestingly, sub-MIC concentrations of PLNC8 αβ substantially enhanced the effects of different antibiotics in an additive or synergistic manner. This study shows that PLNC8 αβ is active against Staphylococcus spp. and may be developed as adjuvant in combination therapy to potentiate the effects of antibiotics and reduce their overall use.

Place, publisher, year, edition, pages
Nature Publishing Group, 2020
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-80305 (URN)10.1038/s41598-020-60570-w (DOI)000560075900001 ()32107445 (PubMedID)2-s2.0-85081035544 (Scopus ID)
Funder
Magnus Bergvall Foundation, 2015-00823Knowledge Foundation, 20150244 20150086Swedish Research Council, 2016-04874 2017-04475Swedish Cancer Society, 17 0532Swedish Foundation for Strategic Research , RMX18-0039
Note

Funding Agencies:

Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University  2009-00971

Örebro University

Erratum in Author Correction: Plantaricin NC8 αβ exerts potent antimicrobial activity against Staphylococcus spp. and enhances the effects of antibiotics. Bengtsson T, Selegård R, Musa A, Hultenby K, Utterström J, Sivlér P, Skog M, Nayeri F, Hellmark B, Söderquist B, Aili D, Khalaf H. Sci Rep. 2020 Sep 24;10(1):16027. doi: 10.1038/s41598-020-72918-3.

Available from: 2020-03-03 Created: 2020-03-03 Last updated: 2024-01-02Bibliographically approved
Tevell, S., Baig, S., Hellmark, B., Martins Simoes, P., Wirth, T., Butin, M., . . . Stegger, M. (2020). Presence of the neonatal Staphylococcus capitis outbreak clone (NRCS-A) in prosthetic joint infections. Scientific Reports, 10(1), Article ID 22389.
Open this publication in new window or tab >>Presence of the neonatal Staphylococcus capitis outbreak clone (NRCS-A) in prosthetic joint infections
Show others...
2020 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 22389Article in journal (Refereed) Published
Abstract [en]

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 SCCmec-SCCcad/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.

Place, publisher, year, edition, pages
Nature Publishing Group, 2020
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-88427 (URN)10.1038/s41598-020-79225-x (DOI)000603610400005 ()33372186 (PubMedID)2-s2.0-85098261349 (Scopus ID)
Note

Funding Agencies:

Research committee of Värmland County Council, Sweden LIVFOU-644591 LIVFOU-736151 LIVFOU84251 LIVFOU-776591 LIVFOU-834801

Research committee of Östergötland County Council, Sweden LIO-447091

Örebro University, Sweden ORU 1.3.1-01273/2015

Foundation for Medical Research at Örebro University Hospital (Nyckelfonden) OLL-502241

Available from: 2021-01-12 Created: 2021-01-12 Last updated: 2022-09-15Bibliographically approved
Stenmark, B., Hellmark, B. & Söderquist, B. (2019). Genomic analysis of Staphylococcus capitis isolated from blood cultures in neonates at a neonatal intensive care unit in Sweden. European Journal of Clinical Microbiology and Infectious Diseases, 38(11), 2069-2075
Open this publication in new window or tab >>Genomic analysis of Staphylococcus capitis isolated from blood cultures in neonates at a neonatal intensive care unit in Sweden
2019 (English)In: European Journal of Clinical Microbiology and Infectious Diseases, ISSN 0934-9723, E-ISSN 1435-4373, Vol. 38, no 11, p. 2069-2075Article in journal (Refereed) Published
Abstract [en]

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.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Coagulase negative staphylococci, NRCS-A clone, Neonatal intensive care unit, S. capitis, Whole-genome sequencing
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-75811 (URN)10.1007/s10096-019-03647-3 (DOI)000491944700010 ()31396832 (PubMedID)2-s2.0-85070296964 (Scopus ID)
Note

Funding Agencies:

Örebro County Research Council 

Örebro University 

Available from: 2019-08-23 Created: 2019-08-23 Last updated: 2019-11-15Bibliographically approved
Magnusson, C., Stegger, M., Hellmark, B., Stenmark, B. & Söderquist, B. (2019). Staphylococcus aureus isolates from nares of orthopaedic patients in Sweden are mupirocin susceptible [Letter to the editor]. Infectious Diseases, 51(6), 475-478
Open this publication in new window or tab >>Staphylococcus aureus isolates from nares of orthopaedic patients in Sweden are mupirocin susceptible
Show others...
2019 (English)In: Infectious Diseases, ISSN 2374-4235, E-ISSN 2374-4243, Vol. 51, no 6, p. 475-478Article in journal, Letter (Refereed) Published
Place, publisher, year, edition, pages
Taylor & Francis, 2019
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-73786 (URN)10.1080/23744235.2019.1593500 (DOI)000466685100001 ()30985251 (PubMedID)2-s2.0-85064501385 (Scopus ID)
Note

Funding Agency:

Nyckelfonden at Örebro University Hospital  OLL-248651

Available from: 2019-04-16 Created: 2019-04-16 Last updated: 2020-12-01Bibliographically approved
Stenmark, B., Hellmark, B. & Söderquist, B. (2018). Increase of S. capitis in neonates with bacteremia in Sweden due to the emergence of a multidrug-resistant clone. In: : . Paper presented at 28th European Congress of Clinical Microbiology and Infectious Diseases, Madrid, Spain, 21-24 April, 2018.
Open this publication in new window or tab >>Increase of S. capitis in neonates with bacteremia in Sweden due to the emergence of a multidrug-resistant clone
2018 (English)Conference paper, Poster (with or without abstract) (Refereed)
Abstract [en]

Background: Staphylococcus capitis has traditionally been considered a commensal due to its low pathogenicity in healthy adults; however, it has been shown to cause 20% of all cases of neonatal sepsis in neonatal intensive care units (NICUs). In addition, S. capitis strains with reduced susceptibility to last line anti-staphylococcal agents such as vancomycin and linezolid are emerging in NICUs. The aim of this study was to characterize S. capitis isolated from blood in a Swedish NICU and to investigate if the multidrug-resistant clone NRCS-A has disseminated in Sweden.

Materials/methods: All S. capitis isolates from neonatal blood cultures collected at Örebro University Hospital during 1987 to the 1st of March 2017 (n=42), were included. Several more episodes of neonatal sepsis with growth of coagulase-negative staphylococci were registered during this time period but probably considered as contaminants and therefore not preserved. Antibiotic susceptibility testing was performed using standardized disc diffusion method on cefoxitin, fusidic acid, clindamycin, erythromycin, gentamicin, rifampicin, trimethroprim/sulfamethoxazole and norfloxacin. Isolates resistant to ≥3 antibiotics were defined as multidrug-resistant. The isolates were whole genome sequenced using the Nextera XT kit (Illumina) on a MiSeq (Illumina). Single nucleotide polymorphisms found with the online tool REALPHY 1.12 in the alignments of shared homologous sites with the reference (the S. capitis NRCS-A strain CR01) were used to create phylogenetic trees.

Results: Seventeen isolates out of the 42 isolates (40%) were multidrug-resistant (resistant to fusidic acid, cefoxitin and gentamicin) and 33 out of the 42 isolates (79%) clustered with the multi-resistant NRCS-A clone (Figure 1). The earliest isolate within the NRCS-A cluster was from 2001.

Conclusions: Although prevalent since 2001, the increase of S. capitis in neonates with bacteremia since 2010 in Örebro county is mainly due to the dissemination of the multidrug-resistant NRCS-A clone and therefore warrants increased surveillance of the epidemiology and etiology of neonatal sepsis to prevent the spread of this clone.

National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-67258 (URN)
Conference
28th European Congress of Clinical Microbiology and Infectious Diseases, Madrid, Spain, 21-24 April, 2018
Available from: 2018-06-14 Created: 2018-06-14 Last updated: 2020-12-01Bibliographically approved
Khan, F. A., Hellmark, B., Ehricht, R., Söderquist, B. & Jass, J. (2018). Related carbapenemase-producing Klebsiella isolates detected in both a hospital and associated aquatic environment in Sweden. European Journal of Clinical Microbiology and Infectious Diseases, 37(12), 2241-2251
Open this publication in new window or tab >>Related carbapenemase-producing Klebsiella isolates detected in both a hospital and associated aquatic environment in Sweden
Show others...
2018 (English)In: European Journal of Clinical Microbiology and Infectious Diseases, ISSN 0934-9723, E-ISSN 1435-4373, Vol. 37, no 12, p. 2241-2251Article in journal (Refereed) Published
Abstract [en]

Carbapenem antibiotics are one of the last-resort agents against multidrug-resistant (MDR) bacteria. The occurrence of carbapenemase-producing Enterobacteriaceae (CPE) in wastewater and aquatic environments is an indication of MDR bacteria in the community. This study evaluated CPE in aquatic environments and compared them to the local hospital isolates in Sweden. Phenotypic and genotypic analyses of antibiotic resistance of environmental and clinical CPE were performed. The relatedness of the isolates and possible clonal dissemination was evaluated using phylogenetic and phyloproteomic analysis. Klebsiella oxytoca carrying carbapenemase genes (blaVIM-1, blaIMP-29) were isolated from wastewater and the recipient river, while K. oxytoca (blaVIM-1) and Klebsiella pneumoniae (blaVIM-1, blaOXA-48, blaNDM-1, blaKPC-3) were isolated from patients at the local clinics or hospital. The K. oxytoca classified as sequence type 172 (ST172) isolated from the river was genotypically related to two clinical isolates recovered from patients. The similarity between environmental and clinical isolates suggests the dispersion of blaVIM-1 producing K. oxytoca ST172 from hospital to aquatic environment and the likelihood of its presence in the community. This is the first report of CPE in aquatic environments in Sweden; therefore, surveillance of aquatic and hospital environments for CPE in other urban areas is important to determine the major transfer routes in order to formulate strategies to prevent the spread of MDR bacteria.

Place, publisher, year, edition, pages
Springer, 2018
Keywords
Antimicrobial resistance, Carbapenemase-producing Enterobacteriaceae, Extended spectrum beta-lactamase, Klebsiella oxytoca, Klebsiella pneumoniae, Multidrug resistance
National Category
Infectious Medicine Microbiology in the medical area
Identifiers
urn:nbn:se:oru:diva-68676 (URN)10.1007/s10096-018-3365-9 (DOI)000449921100003 ()30171482 (PubMedID)2-s2.0-85053311566 (Scopus ID)
Funder
Swedish Research Council Formas, 219-2014-837
Note

Funding Agency:

Nyckelfonden at Orebro University Hospital 

Available from: 2018-09-03 Created: 2018-09-03 Last updated: 2020-12-01Bibliographically approved
Salih, L., Tevell, S., Månsson, E., Nilsdotter-Augustinsson, Å., Hellmark, B. & Söderquist, B. (2018). Staphylococcus epidermidis isolates from nares and prosthetic joint infections are mupirocin susceptible. Journal of bone and joint infection, 3(1), 1-4
Open this publication in new window or tab >>Staphylococcus epidermidis isolates from nares and prosthetic joint infections are mupirocin susceptible
Show others...
2018 (English)In: Journal of bone and joint infection, ISSN 2206-3552, Vol. 3, no 1, p. 1-4Article in journal (Refereed) Published
Abstract [en]

The objective of the present study was to investigate the antibiotic susceptibility including mupirocin among Staphylococcus. epidermidis isolated from prosthetic joint infections (PJIs) (n=183) and nasal isolates (n=75) from patients intended to undergo prosthetic joint replacements. Susceptibility to mupirocin (used for eradication of nasal carriership of Staphylococcus aureus) was investigated by gradient test, and susceptibility to various other antimicrobial agents was investigated by disc diffusion test. All isolates, except three from PJIs and one from the nares, were fully susceptible to mupirocin. Multi-drug resistance (≥3 antibiotic classes) was found in 154/183 (84.2%) of the PJI isolates but only in 2/75 (2.7%) of the nares isolates, indicating that S. epidermidis causing PJIs do not originate from the nares.

Place, publisher, year, edition, pages
Ivyspring International Publisher, 2018
Keywords
Antibiotic susceptibility testing, Mupirocin, Prosthetic joint infections, Staphylococcus epidermidis
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-64047 (URN)10.7150/jbji.22459 (DOI)29291157 (PubMedID)2-s2.0-85086908988 (Scopus ID)
Available from: 2018-01-12 Created: 2018-01-12 Last updated: 2023-12-08Bibliographically approved
Söderquist, B., Björklund, S., Hellmark, B., Jensen, A. & Brüggemann, H. (2017). Finegoldia magna Isolated from Orthopedic Joint Implant-Associated Infections. Journal of Clinical Microbiology, 55(11), 3283-3291
Open this publication in new window or tab >>Finegoldia magna Isolated from Orthopedic Joint Implant-Associated Infections
Show others...
2017 (English)In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 55, no 11, p. 3283-3291Article in journal (Refereed) Published
Abstract [en]

The anaerobic Gram-positive coccus Finegoldia magna is a rare cause of infections of bone and joints. The aim of this study was to describe the microbiological and clinical characteristics of orthopedic implant-associated infections caused by F. magna We retrospectively analyzed samples consisting of anaerobic Gram-positive cocci and samples already identified as F. magna from patients with orthopedic infections. The isolates found were determined to the species level using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The antibiotic susceptibility pattern was determined by Etest. Whole-genome sequencing (WGS) was performed. Clinical data were extracted from each patient's journal. In nine patients, orthopedic joint implant-associated infections were identified as being caused by F. magna The isolates were susceptible to most of the antibiotics tested, with the exception of rifampin and moxifloxacin in a few cases. Five of the nine infections were monomicrobial. The most common antibiotic used to treat the infection was penicillin V, but five of the nine patients received a combination of antibiotics. Eight patients underwent surgical treatment, with extraction of the implant performed in seven cases and reimplantation in only two cases. The WGS showed a relatively small core genome, with 126,647 single nucleotide polymorphisms identified within the core genome. A phylogenomic analysis revealed that the isolates clustered into two distinct clades. Orthopedic implant-associated infections caused by F. magna are rare, but the bacteria are generally susceptible to antibiotics. Despite this, surgical treatment combined with long-term antibiotics is often necessary. The WGS analysis revealed a high heterogeneity and suggested the existence of at least two different Finegoldia species.

Place, publisher, year, edition, pages
American Society for Microbiology, 2017
Keywords
Finegoldia magna, antibiotic susceptibility test, orthopedic implant-associated infections, prosthetic joint infections, whole-genome sequencing
National Category
Infectious Medicine
Identifiers
urn:nbn:se:oru:diva-62478 (URN)10.1128/JCM.00866-17 (DOI)000414356400019 ()28904182 (PubMedID)2-s2.0-85032443997 (Scopus ID)
Note

Funding agencies:

Nyckelfonden at Orebro University Hospital OLL-595951 

Danish Medical Research council DFF-1331-00241 

Available from: 2017-12-04 Created: 2017-12-04 Last updated: 2020-12-01Bibliographically approved
Månsson, E., Hellmark, B., Stegger, M., Andersen, P. S., Sundqvist, M. & Söderquist, B. (2017). Genomic relatedness of Staphylococcus pettenkoferi isolates of different origins. Journal of Medical Microbiology, 66(5), 601-608
Open this publication in new window or tab >>Genomic relatedness of Staphylococcus pettenkoferi isolates of different origins
Show others...
2017 (English)In: Journal of Medical Microbiology, ISSN 0022-2615, E-ISSN 1473-5644, Vol. 66, no 5, p. 601-608Article in journal (Refereed) Published
Abstract [en]

Purpose: The aim of the study was to characterize clinical and environmental Staphylococcus pettenkoferi isolates with regard to genomic diversity and antibiotic susceptibility pattern. Repetitive-sequence-based PCR and core genome phylogenetic analysis of whole-genome sequencing (WGS) data verified the presence of distinct clades comprising closely related S. pettenkoferi isolates from different geographical locations and origins.

Methodology: Phylogenetic relationships between 25 S. pettenkoferi isolates collected from blood cultures and intra-operative air sampling were determined by repetitive-sequence-based PCR typing and analysis of similar to 157 000 SNPs identified in the core genome after WGS. Antibiotic susceptibility testing and tests for biofilm production (microtitre plate assay) were performed.

Results: Repetitive-sequence-based PCR as well as WGS data demonstrated the close relatedness of clinically significant blood culture isolates to probable contaminants, as well as to environmental isolates. Antibiotic-susceptibility testing demonstrated a low level of antimicrobial resistance. The mecA gene was present in two cefoxitin-resistant isolates. No isolates were found to produce biofilm.

Conclusion: Close genomic relatedness of S. pettenkoferi isolates from different geographical locations and origins were found within clades, but with substantial genomic difference between the two major clades. The ecological niche of S. pettenkoferi remains unconfirmed, but the presence of S. pettenkoferi in the air of the operating field favours the suggestion of a role in skin flora. Identification of S. pettenkoferi in clinical samples should, in a majority of cases, most likely be regarded as a probable contamination, and its role as a possible pathogen in immunocompromised hosts remains to be clarified.

Place, publisher, year, edition, pages
Microbiology Society, 2017
Keywords
Staphylococcus pettenkoferi, genotypic relatedness, repetitive-sequence based PCR typing, whole-genome sequencing
National Category
Microbiology in the medical area
Identifiers
urn:nbn:se:oru:diva-58000 (URN)10.1099/jmm.0.000472 (DOI)000401984900007 ()28530888 (PubMedID)2-s2.0-85019900525 (Scopus ID)
Note

Funding Agencies:

Örebro County Council Research Committee, Örebro, Sweden

Centre for Clinical Research, Västerås  

County Council of Västmanland Research Fund 

Available from: 2017-06-13 Created: 2017-06-13 Last updated: 2020-12-01Bibliographically approved
Organisations

Search in DiVA

Show all publications