| 1. |
- Gomila, Margarita, et al.
(author)
-
Genotypic and phenotypic applications for the differentiation and species-level identification of achromobacter for clinical diagnoses.
- 2014
-
In: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 9:12
-
Journal article (peer-reviewed)abstract
- The Achromobacter is a genus in the family Alcaligenaceae, comprising fifteen species isolated from different sources, including clinical samples. The ability to detect and correctly identify Achromobacter species, particularly A. xylosoxidans, and differentiate them from other phenotypically similar and genotypically related Gram-negative, aerobic, non-fermenting species is important for patients with cystic fibrosis (CF), as well as for nosocomial and other opportunistic infections. Traditional phenotypic profile-based analyses have been demonstrated to be inadequate for reliable identifications of isolates of Achromobacter species and genotypic-based assays, relying upon comparative 16S rRNA gene sequence analyses are not able to insure definitive identifications of Achromobacter species, due to the inherently conserved nature of the gene. The uses of alternative methodologies to enable high-resolution differentiation between the species in the genus are needed. A comparative multi-locus sequence analysis (MLSA) of four selected 'house-keeping' genes (atpD, gyrB, recA, and rpoB) assessed the individual gene sequences for their potential in developing a reliable, rapid and cost-effective diagnostic protocol for Achromobacter species identifications. The analysis of the type strains of the species of the genus and 46 strains of Achromobacter species showed congruence between the cluster analyses derived from the individual genes. The MLSA gene sequences exhibited different levels of resolution in delineating the validly published Achromobacter species and elucidated strains that represent new genotypes and probable new species of the genus. Our results also suggested that the recently described A. spritinus is a later heterotypic synonym of A. marplatensis. Strains were analyzed, using whole-cell Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight mass spectrometry (MALDI-TOF MS), as an alternative phenotypic profile-based method with the potential to support the identifications determined by the genotypic DNA sequence-based MLSA. The MALDI-TOF MS data showed good accordance in strain groupings and identifications by the MLSA data.
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| 2. |
- Grankvist, Anna, et al.
(author)
-
Multilocus sequence analysis of clinical "candidatus neoehrlichia mikurensis" strains from Europe
- 2015
-
In: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 53:10, s. 3126-3132
-
Journal article (peer-reviewed)abstract
- Copyright © 2015, American Society for Microbiology. All Rights Reserved. Candidatus Neoehrlichia mikurensis" is the tick-borne agent of neoehrlichiosis, an infectious disease that primarily affects immunocompromised patients. So far, the genetic variability of "Ca. Neoehrlichia" has been studied only by comparing 16S rRNA genes and groEL operon sequences. We describe the development and use of a multilocus sequence analysis (MLSA) protocol to characterize the genetic diversity of clinical "Ca. Neoehrlichia" strains in Europe and their relatedness to other species within the Anaplasmataceae family. Six genes were selected: ftsZ, clpB, gatB, lipA, groEL, and 16S rRNA. Each MLSA locus was amplified by real-time PCR, and the PCR products were sequenced. Phylogenetic trees of MLSA locus relatedness were constructed from aligned sequences. Blood samples from 12 patients with confirmed "Ca. Neoehrlichia" infection from Sweden (n9), the Czech Republic (n2), and Germany (n1) were analyzed with the MLSA protocol. Three of the Swedish strains exhibited identical lipA sequences, while the lipA sequences of the strains from the other nine patients were identical to each other. One of the Czech strains had one differing nucleotide in the clpB sequence from the sequences of the other 11 strains. All 12 strains had identical sequences for the genes 16S rRNA, ftsZ, gatB, and groEL. According to the MLSA, among the Anaplasmataceae, "Ca. Neoehrlichia" is most closely related to Ehrlichia ruminantium, less so to Anaplasma phagocytophilum, and least to Wolbachia endosymbionts. To conclude, three sequence types of infectious "Ca. Neoehrlichia" were identified: one in the west of Sweden, one in the Czech Republic, and one spread throughout Europe.
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| 3. |
- Hedberg, Maria E, et al.
(author)
-
Lachnoanaerobaculum gen. nov., a new genus in the Lachnospiraceae: characterization of Lachnoanaerobaculum umeaense gen. nov., sp. nov., isolated from the human small intestine, and Lachnoanaerobaculum orale sp. nov., isolated from saliva, and reclassification of Eubacterium saburreum (Prevot 1966) Holdeman and Moore 1970 as Lachnoanaerobaculum saburreum comb. nov.
- 2012
-
In: International journal of systematic and evolutionary microbiology. - : Microbiology Society. - 1466-5034 .- 1466-5026. ; 62:Pt 11, s. 2685-90
-
Journal article (peer-reviewed)abstract
- Two novel obligately anaerobic, Gram-stain-positive, saccharolytic and non-proteolytic spore-forming bacilli (strains CD3:22(T) and N1(T)) are described. Strain CD3:22(T) was isolated from a biopsy of the small intestine of a child with coeliac disease, and strain N1(T) from the saliva of a healthy young man. The cells of both strains were observed to be filamentous, approximately 5 to >20 µm long, some of them curving and with swellings. The novel organisms produced H(2)S, NH(3), butyric acid and acetic acid as major metabolic end products. Phylogenetic analyses, based on comparative 16S rRNA gene sequencing, revealed close relationships (98% sequence similarity) between the two isolates, as well as the type strain of Eubacterium saburreum and four other Lachnospiraceae bacterium-/E. saburreum-like organisms. This group of bacteria were clearly different from any of the 19 known genera in the family Lachnospiraceae. While Eubacterium species are reported to be non-spore-forming, reanalysis of E. saburreum CCUG 28089(T) confirmed that the bacterium is indeed able to form spores. Based on 16S rRNA gene sequencing, phenotypic and biochemical properties, strains CD3:22(T) and N1(T) represent novel species of a new and distinct genus, named Lachnoanaerobaculum gen. nov., in the family Lachnospiraceae [within the order Clostridiales, class Clostridia, phylum Firmicutes]. Strain CD3:22(T) (=CCUG 58757(T) =DSM 23576(T)) is the type strain of the type species, Lachnoanaerobaculum umeaense gen. nov., sp. nov., of the proposed new genus. Strain N1(T) (=CCUG 60305(T)=DSM 24553(T)) is the type strain of Lachnoanaerobaculum orale sp. nov. Moreover, Eubacterium saburreum is reclassified as Lachnoanaerobaculum saburreum comb. nov. (type strain CCUG 28089(T) =ATCC 33271(T) =CIP 105341(T) =DSM 3986(T) =JCM 11021(T) =VPI 11763(T)).
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| 4. |
- Hedberg, Maria E., et al.
(author)
-
Prevotella jejuni sp. nov., isolated from the small intestine of a child with celiac disease.
- 2013
-
In: International journal of systematic and evolutionary microbiology. - : Microbiology Society. - 1466-5034 .- 1466-5026. ; 63:11, s. 4218-4223
-
Journal article (peer-reviewed)abstract
- Five obligately anaerobic, Gram-negative, saccharolytic and proteolytic, non-spore-forming bacilli (CD3:27, CD3:28T, CD3:33, CD3:32 and CD3:34) are described. All five strains were isolated from the small intestine of a female child with celiac disease. The cells of the five strains were observed to be short rods or coccoid cells with longer filamentous forms seen sporadically. The organisms produced acetic acid and succinic acid as major metabolic end products. Phylogenetic analysis, based on comparative 16S rRNA gene sequence analysis revealed close relationships between CD3:27, CD3:28T and CD3:33 on one hand, between CD3:32 and P. histicola CCUG 55407T and between CD3:34 and P. melaninogenica CCUG 4944BT on the other. The strains CD3:27, CD3:28T and CD3:33 were clearly different from any other species within the genus Prevotella and most closely related to but distinct from P. melaninogenica. Based on 16S rRNA gene, RNA polymerase β-subunit gene and 60-kDa chaperonin protein subunit gene sequencing, phenotypic, chemical and biochemical properties strains CD3:27, CD3:28T and CD3:33 have been determined to represent a novel species within the genus Prevotella, named Prevotella jejuni sp. nov. Strain CD3:28T (CCUG 60371T = DSM 26989T) is the type strain of the proposed new species. All five strains were able to form homologous aggregates, in which tube-like structures were connecting individual bacteria cells. The five strains were able to bind to human intestinal carcinoma cell lines at 37 °C.
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| 5. |
- Isaksson, Jenny, et al.
(author)
-
Comparison of species identification of endocarditis associated viridans streptococci using rnpB genotyping and 2 MALDI-TOF systems
- 2015
-
In: Diagnostic Microbiology and Infectious Disease. - : Elsevier BV. - 0732-8893 .- 1879-0070. ; 81:4, s. 240-245
-
Journal article (peer-reviewed)abstract
- Streptococcus spp. are important causes of infective endocarditis but challenging in species identification. This study compared identification based on sequence determination of the rnpB gene with 2 systems of matrix-assisted laser desorption ionization-time of flight mass spectrometry, MALDI Biotyper (Bruker) and VITEK MS IVD (bioMerieux). Blood culture isolates of viridans streptococci from 63 patients with infective endocarditis were tested. The 3 methods showed full agreement for all 36 isolates identified in the Anginosus, Bovis, and Mutans groups or identified as Streptococcus cristatus, Streptococcus gordonii, or Streptococcus sanguinis. None of the methods could reliably identify the 23 isolates to the species level when designated as Streptococcus mitis, Streptococcus oralis, or Streptococcus tigurinus. In 7 isolates classified to the Mitis group, the rnpB sequences deviated strikingly from all reference sequences, and additional analysis of sodA and groEL genes indicated the occurrence of yet unidentified Streptococcus spp. (C) 2015 Elsevier Inc. All rights reserved.
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| 6. |
- Jaén-Luchoro, Daniel, et al.
(author)
-
Corynebacterium sanguinis sp. nov., a clinical and environmental associated corynebacterium.
- 2020
-
In: Systematic and applied microbiology. - : Elsevier BV. - 1618-0984 .- 0723-2020. ; 43:1
-
Journal article (peer-reviewed)abstract
- Clinical and environmental-associated strains (n=17), genotypically related to Corynebacterium spp., yet distinct from any species of the genus Corynebacterium with validly published names, have been isolated during the last 20 years and tentatively identified as Corynebacterium sanguinis, although the combination, "Corynebacterium sanguinis" was never validly published. The comprehensive genotypic and phenotypic characterisations and genomic analyses in this study support the proposal for recognizing the species within the genus Corynebacterium, for which the name, Corynebacterium sanguinis sp. nov., is reaffirmed and proposed. Strains of Corynebacterium sanguinis are Gram-positive, non-motile, non-spore-forming, short, pleomorphic and coryneform bacilli, growing aerobically, with CO2. They contain mycolic acids, major respiratory menaquinones, MK-8 (II-H2) and MK-9 (II-H2), and polar lipids, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphoglycolipid, glycolipids and a novel lipid that remains to be characterized and identified. Strains of Corynebacterium sanguinis are genotypically most similar to Corynebacterium lipophiliflavum, with 16S rRNA gene sequence similarities of 98.3% and rpoB sequence similarities of 94.9-95.2%. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis were able to clearly differentiate Corynebacterium sanguinis from the most closely related species. The genome size of Corynebacterium sanguinis is 2.28-2.37Mbp with 65.1-65.5mol% G+C content. A total of 2202-2318 ORFs were predicted, comprising 2141-2251 protein-encoding genes. The type strain is CCUG 58655T (=CCM 8873T=NCTC 14287T).
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| 7. |
- Johnning, Anna, 1985, et al.
(author)
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Acquired genetic mechanisms of a multiresistant bacterium isolated from a treatment plant receiving wastewater from antibiotic production.
- 2013
-
In: Applied and environmental microbiology. - 1098-5336 .- 0099-2240. ; 79:23, s. 7256-63
-
Journal article (peer-reviewed)abstract
- The external environment, particularly wastewater treatment plants (WWTPs), where environmental bacteria meet human commensals and pathogens in large numbers, has been highlighted as a potential breeding ground for antibiotic resistance. We have isolated the extensively drug-resistant Ochrobactrum intermedium CCUG 57381 from an Indian WWTP receiving industrial wastewater from pharmaceutical production contaminated with high levels of quinolones. Antibiotic susceptibility testing against 47 antibiotics showed that the strain was 4 to >500 times more resistant to sulfonamides, quinolones, tetracyclines, macrolides, and the aminoglycoside streptomycin than the type strain O. intermedium LMG 3301(T). Whole-genome sequencing identified mutations in the Indian strain causing amino acid substitutions in the target enzymes of quinolones. We also characterized three acquired regions containing resistance genes to sulfonamides (sul1), tetracyclines [tet(G) and tetR], and chloramphenicol/florfenicol (floR). Furthermore, the Indian strain harbored acquired mechanisms for horizontal gene transfer, including a type I mating pair-forming system (MPFI), a MOBP relaxase, and insertion sequence transposons. Our results highlight that WWTPs serving antibiotic manufacturing may provide nearly ideal conditions for the recruitment of resistance genes into human commensal and pathogenic bacteria.
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| 8. |
- Karlsson, R., et al.
(author)
-
Proteotyping: Proteomic characterization, classification and identification of microorganisms - A prospectus
- 2015
-
In: Systematic and Applied Microbiology. - : Elsevier BV. - 0723-2020. ; 38:4, s. 246-257
-
Research review (peer-reviewed)abstract
- Modern microbial systematics requires a range of methodologies for the comprehensive characterization, classification and identification of microorganisms. While whole-genome sequences provide the ultimate reference for defining microbial phylogeny and taxonomy, selected biomarker-based strategies continue to provide the means for the bulk of microbial systematic studies. Proteomics, the study of the expression of genes, as well as the structure and function of the resulting proteins, offers indirect measures of genome sequence data. Recent developments in applications of proteomics for analyzing microorganisms have paralleled the growing microbial genome sequence database, as well as the evolution of mass spectrometry (MS) instrumentation and bioinformatics. MALDI-TOF MS, which generates proteomic mass patterns for 'fingerprint'-based characterizations, has provided a marked breakthrough for microbial identification. However, MALDI-TOF MS is limited in the number of targets that can be detected for strain characterization. Advanced methods of tandem mass spectrometry, in which proteins and peptides generated from proteins, are characterized and identified, using LC-MS/MS, provide the ability to detect hundreds or thousands of expressed microbial strain markers for high-resolution characterizations and identifications. Model studies demonstrate the application of proteomics-based analyses for bacterial species- and strain-level detection and identification and for characterization of environmentally relevant, metabolically diverse bacteria. Proteomics-based approaches represent an emerging complement to traditional methods of characterizing microorganisms, enabling the elucidation of the expressed biomarkers of genome sequence information, which can be applied to 'proteotyping' applications of microorganisms at all taxonomic levels. (C) 2015 Elsevier GmbH. All rights reserved.
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| 9. |
- Karlsson, Roger, et al.
(author)
-
Proteotyping: Tandem Mass Spectrometry Shotgun Proteomic Characterization and Typing of Pathogenic Microorganisms
- 2016
-
In: MALDI‐TOF and Tandem MS for Clinical Microbiology. - Chichester, UK : John Wiley & Sons, Ltd. - 9781118960226 ; , s. 419-450
-
Book chapter (other academic/artistic)abstract
- Proteotyping provides the means to identify and quantify the actual expression patterns of proteins and their associated pathways, which provides a more accurate picture of infectious agents and their pathogenic potential. Proteotyping, as an analytical method, is intimately correlated with genotypic or genomic data and offers an approach for a holistic characterization of microorganisms. Bioinformatics is vital for the analysis of the data generated by shotgun proteomics. This chapter describes the complete bioinformatics workflow necessary for proteotyping. Mass spectrometry (MS)-based shotgun proteomics analyses offer more detailed and comprehensive analyses of microorganisms. Two approaches may be applied: the so-called top-down and bottom-up proteomics. A major driver for the development and use of tandem MS and proteotyping in clinical settings will be the rapidly growing databases of whole genome reference sequences, which will refine microbial phylogeny and provide a foundation for proteomics-based identification.
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| 10. |
- Karlsson, Roger, 1975, et al.
(author)
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Strain-level typing and identification of bacteria using mass spectrometry-based proteomics.
- 2012
-
In: Journal of proteome research. - : American Chemical Society (ACS). - 1535-3907 .- 1535-3893. ; 11:5, s. 2710-20
-
Journal article (peer-reviewed)abstract
- Because of the alarming expansion in the diversity and occurrence of bacteria displaying virulence and resistance to antimicrobial agents, it is increasingly important to be able to detect these microorganisms and to differentiate and identify closely related species, as well as different strains of a given species. In this study, a mass spectrometry proteomics approach is applied, exploiting lipid-based protein immobilization (LPI), wherein intact bacterial cells are bound, via membrane-gold interactions, within a FlowCell. The bound cells are subjected to enzymatic digestion for the generation of peptides, which are subsequently identified, using LC-MS. Following database matching, strain-specific peptides are used for subspecies-level discrimination. The method is shown to enable a reliable typing and identification of closely related strains of the same bacterial species, herein illustrated for Helicobacter pylori .
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| 11. |
- Lindgren, Åsa, 1979, et al.
(author)
-
Development of a rapid MALDI-TOF MS based epidemiological screening method using MRSA as a model organism
- 2018
-
In: European Journal of Clinical Microbiology & Infectious Diseases. - : Springer Science and Business Media LLC. - 0934-9723 .- 1435-4373. ; 37:1, s. 57-68
-
Journal article (peer-reviewed)abstract
- In this study we present a method using whole cell MALDI-TOF MS and VITEK MS RUO/SARAMIS as a rapid epidemiological screening tool. MRSA was used as a model organism for setting up the screening strategy. A collection of well-characterised MRSA strains representing the 19 most common Pulsed-Field Gel Electrophoresis (PFGE)-types in the region of South-West Sweden for the past 20 years was analysed with MALDI-TOF MS. A total of 111 MRSA strains were used for creating 19 PFGE-specific Superspectra using VITEK MS RUO/SARAMIS. Prior to performing the final analysis, the 19 Superspectra were combined into ten groups displaying similar peak patterns, hereafter named "MALDI-types". Two-hundred fifty-five MRSA strains were analysed to test the constructed Superspectra/MALDI-type database. Matches to the Superspectra above a threshold of 65% (corresponding to the number of matched peaks in the Superspectrum) were considered as positive assignment of a strain to a MALDI-type. The median peak matching value for correct assignment of a strain to a MALDI-type was 78% (range 65.3-100%). In total, 172 strains (67.4%) were assigned to the correct MALDI-type and only 5.5% of the strains were incorrectly assigned to another MALDI-type than the expected based on the PFGE-type of the strain. We envision this methodology as a cost-efficient step to be used as a first screening strategy in the typing scheme of MRSA isolates, to exclude epidemiological relatedness of isolates or to identify the need for further typing.
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| 12. |
- Marathe, Nachiket, et al.
(author)
-
Scandinavium goeteborgense gen. nov., sp. nov., a New Member of the Family Enterobacteriaceae Isolated From a Wound Infection, Carries a Novel Quinolone Resistance Gene Variant
- 2019
-
In: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 10:10
-
Journal article (peer-reviewed)abstract
- © Copyright © 2019 Marathe, Salvà-Serra, Karlsson, Larsson, Moore, Svensson-Stadler and Jakobsson. The family Enterobacteriaceae is a taxonomically diverse and widely distributed family containing many human commensal and pathogenic species that are known to carry transferable antibiotic resistance determinants. Characterization of novel taxa within this family is of great importance in order to understand the associated health risk and provide better treatment options. The aim of the present study was to characterize a Gram-negative bacterial strain (CCUG 66741) belonging to the family Enterobacteriaceae, isolated from a wound infection of an adult patient, in Sweden. Initial phenotypic and genotypic analyses identified the strain as a member of the family Enterobacteriaceae but could not assign it to any previously described species. The complete 16S rRNA gene sequence showed highest similarity (98.8%) to four species. Whole genome sequencing followed by in silico DNA-DNA similarity analysis and average nucleotide identity (ANI) analysis confirmed that strain CCUG 66741 represents a novel taxon. Sequence comparisons of six house-keeping genes (16S rRNA, atpD, dnaJ, gyrB, infB, rpoB) with those of the type strains of the type species of related genera within the family Enterobacteriaceae indicated that the strain embodies a novel species within the family. Phylogenomic analyses (ANI-based and core genome-based phylogeny) showed that strain CCUG 66741 forms a distinct clade, representing a novel species of a distinct, new genus within the family Enterobacteriaceae, for which the name Scandinavium goeteborgense gen. nov., sp. nov. is proposed, with CCUG 66741T as the type strain (= CECT 9823T = NCTC 14286T). S. goeteborgense CCUG 66741T carries a novel variant of a chromosomally-encoded quinolone resistance gene (proposed qnrB96). When expressed in Escherichia coli, the qnrB96 gene conferred five-fold increase in minimum inhibitory concentration against ciprofloxacin. This study highlights the importance and the utility of whole genome sequencing for pathogen identification in clinical settings.
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| 13. |
- Narciso-da-Rocha, Carlos, et al.
(author)
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Diversity and antibiotic resistance of Acinetobacter spp. in water from the source to the tap.
- 2013
-
In: Applied Microbiology and Biotechnology. - : Springer Science and Business Media LLC. - 0175-7598 .- 1432-0614. ; 97:1, s. 329-340
-
Journal article (peer-reviewed)abstract
- Acinetobacter spp. are ubiquitous bacteria in the environment. Acinetobacter spp. isolated from a municipal drinking water treatment plant and from connected tap water were identified to the species level on the basis of rpoB gene partial sequence analysis. Intraspecies variation was assessed based on the analysis of partial sequences of housekeeping genes (rpoB, gyrB, and recA). Antibiotic resistance was characterized using the disk diffusion method and isolates were classified as wild or non-wild type (non-WT), according to the observed phenotype. The strains of Acinetobacter spp. were related to 11 different validly published species, although three groups of isolates, presenting low rpoB sequence similarities with previously described species, may represent new species. Most of the isolates were related to the species A. johnsonii and A. lwoffii. These two groups, as well as others related to the species A. parvus and A. tjernbergiae, were detected in the water treatment plant and in tap water. Other strains, related to the species A. pittii and A. beijerinckii, were isolated only from tap water. Most of the isolates (80%) demonstrated wild type (WT) to all of the 12 antibiotics tested. Non-WT for tetracycline, meropenem, and ceftazidime, among others, were observed in water treatment plant or in tap water samples. Although, in general, this study suggests a low prevalence of acquired antibiotic resistance in water Acinetobacter spp., the potential of some species to acquire and disseminate resistance via drinking water is suggested.
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| 14. |
- Nicklasson, Matilda, 1978, et al.
(author)
-
Pseudomonas boanensis sp. nov., a bacterium isolated from river water used for household purposes in Boane District, Mozambique
- 2022
-
In: International Journal of Systematic and Evolutionary Microbiology. - : Microbiology Society. - 1466-5026 .- 1466-5034. ; 72:7
-
Journal article (peer-reviewed)abstract
- A Gram- negative rod with a single polar flagellum was isolated from a freshwater reservoir used for household purposes in Boane District, near Maputo, Mozambique, and designated as strain DB1T. Growth was observed at 30???42 ??C (optimum, 30???37 ??C) and with 0.5???1.5 % NaCl. Whole- genome-, rpoD- and 16S rRNA- based phylogenies revealed this isolate to be distant from other Pseudomonas species with Pseudomonas resinovorans, Pseudomonas furukawaii and Pseudomonas lalkuanensis being the closest relatives. Phenotypic analyses of strain DB1T showed marked differences with respect to type strains P. resinovorans CCUG 2473T, P. lalkuanensis CCUG 73691T, P. furukawaii CCUG 75672T and Pseudomonas otiditis CCUG 55592T. Taken together, our results indicate that strain DB1T is a representative of a novel species within the genus Pseudomonas for which the name Pseudomonas boanensis is proposed. The type strain is DB1T (=CCUG 62977T=CECT 30359T).
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| 15. |
- Nilsson, Adam, et al.
(author)
-
Competitive binding-based optical DNA mapping for fast identification of bacteria - multi-ligand transfer matrix theory and experimental applications on Escherichia coli.
- 2014
-
In: Nucleic Acids Research. - : Oxford University Press (OUP). - 1362-4962 .- 0305-1048. ; 42:15, s. 118-118
-
Journal article (peer-reviewed)abstract
- We demonstrate a single DNA molecule optical mapping assay able to resolve a specific Escherichia coli strain from other strains. The assay is based on competitive binding of the fluorescent dye YOYO-1 and the AT-specific antibiotic netropsin. The optical map is visualized by stretching the DNA molecules in nanofluidic channels. We optimize the experimental conditions to obtain reproducible barcodes containing as much information as possible. We implement a multi-ligand transfer matrix method for calculating theoretical barcodes from known DNA sequences. Our method extends previous theoretical approaches for competitive binding of two types of ligands to many types of ligands and introduces a recursive approach that allows long barcodes to be calculated with standard computer floating point formats. The identification of a specific E. coli strain (CCUG 10979) is based on mapping of 50-160 kilobasepair experimental DNA fragments onto the theoretical genome using the developed theory. Our identification protocol introduces two theoretical constructs: a P-value for a best experiment-theory match and an information score threshold. The developed methods provide a novel optical mapping toolbox for identification of bacterial species and strains. The protocol does not require cultivation of bacteria or DNA amplification, which allows for ultra-fast identification of bacterial pathogens.
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| 16. |
- Nowrouzian, Forough, 1957, et al.
(author)
-
Staphylococcus aureus sequence type (ST) 45, ST30, and ST15 in the gut microbiota of healthy infants - persistence and population counts in relation to ST and virulence gene carriage
- 2023
-
In: European Journal of Clinical Microbiology & Infectious Diseases. - : Springer Science and Business Media LLC. - 0934-9723 .- 1435-4373. ; 42, s. 267-276
-
Journal article (peer-reviewed)abstract
- Staphylococcus aureus colonizes the anterior nares, and also the gut, particularly in infants. S. aureus is divided into lineages, termed clonal complexes (CCs), which comprise closely related sequence types (STs). While CC30 and CC45 predominate among nasal commensals, their prevalence among gut-colonizing S. aureus is unknown. Here, 67 gut commensal S. aureus strains from 49 healthy Swedish infants (aged 3 days to 12 months) were subjected to multi-locus sequence typing. The STs of these strains were related to their virulence gene profiles, time of persistence in the microbiota, and fecal population counts. Three STs predominated: ST45 (22% of the strains); ST15 (21%); and ST30 (18%). In a logistic regression, ST45 strains showed higher fecal population counts than the others, independent of virulence gene carriage. The lower fecal counts of ST15 were linked to the carriage of fib genes (encoding fibrinogen-binding proteins), while those of ST30 were linked to fib and sea (enterotoxin A) carriage. While only 11% of the ST15 and ST30 strains were acquired after 2 months of age, this was true of 53% of the ST45 strains (p = 0.008), indicating that the former may be less fit for establishment in a more mature microbiota. None of the ST45 strains was transient (persisting < 3 weeks), and persistent ST45 strains colonized for significantly longer periods than persistent strains of other STs (mean, 34 vs 22 weeks, p = 0.04). Our results suggest that ST45 strains are well-adapted for commensal gut colonization in infants, reflecting yet-unidentified traits of these strains.
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| 17. |
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| 18. |
- Nyberg, Lena, 1979, et al.
(author)
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Optical mapping of single DNA molecules in nanochannels: A novel method for identification and characterization of antibiotic resistance
- 2015
-
In: 18th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2014. - 9780979806476 ; , s. 1045-1047
-
Conference paper (peer-reviewed)abstract
- The use, and overuse, of antibiotics has during the last decade led to a dramatic increase in antibiotic resistance and there is a crying need for novel methods for fast identification of antibiotic resistance genes. We here demonstrate how our previously developed assay for optical mapping of DNA in nanochannels can be used for characterization of resistance genes located on plasmid DNA from bacteria. The assay requires extremely small sample volumes and does neither rely on PCR, nor culturing of bacteria, which greatly reduces the time for analysis.
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| 19. |
- Salvà-Serra, Francisco, 1989, et al.
(author)
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Draft Genome Sequence of Streptococcus gordonii Type Strain CCUG 33482T.
- 2016
-
In: Genome Announcements. - 2169-8287. ; 4:2
-
Journal article (peer-reviewed)abstract
- Streptococcus gordoniitype strain CCUG 33482(T)is a member of theStreptococcus mitisgroup, isolated from a case of subacute bacterial endocarditis. Here, we report the draft genome sequence ofS. gordoniiCCUG 33482(T), composed of 41 contigs of a total size of 2.15 Mb with 2,061 annotated coding sequences.
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| 20. |
- Svensson-Stadler, Liselott, 1971, et al.
(author)
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Stenotrophomonas interspecies differentiation and identification by gyrB sequence analysis.
- 2012
-
In: FEMS microbiology letters. - : Oxford University Press (OUP). - 1574-6968 .- 0378-1097. ; 327:1, s. 15-24
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Journal article (peer-reviewed)abstract
- Stenotrophomonas species are found commonly in environmental and clinical samples; Stenotrophomonas maltophilia is an important opportunistic pathogen of humans. Traditional phenotyping protocols, as well as genotyping by 16S rRNA gene sequence analysis, do not reliably distinguish the species of Stenotrophomonas. Sequence analyses of two targeted PCR-amplified regions of the gyrB gene, which encodes the β-subunit of DNA gyrase, enabled resolution and identification of these species. Most type strains of the different species of Stenotrophomonas exhibited more than 7% dissimilarity in the gyrB gene sequences. Among these, strains identified as the same species exhibited sequence dissimilarities up to 4.6% and 5.9% for the two regions, respectively. Strains identified as S. maltophilia, with 16S rRNA gene sequence similarities > 99.0%, were grouped within a 'S. maltophilia complex'; these organisms exhibited gyrB similarities as low as 93%. Many of these strains possessed genomic DNA similarities with the type strain of S. maltophilia CCUG 5866(T) below 70%. These data, including gyrB sequence comparisons, indicate that strains identified as S. maltophilia may comprise distinct, new species.
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| 21. |
- Tång Hallbäck, Erika, 1973, et al.
(author)
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Methicillin-resistant Staphylococcus argenteus misidentified as methicillin-resistant Staphylococcus aureus emerging in western Sweden
- 2018
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In: Journal of Medical Microbiology. - : Microbiology Society. - 0022-2615 .- 1473-5644. ; 67:7, s. 968-971
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Journal article (peer-reviewed)abstract
- Two strains included in a whole-genome sequencing project for methicillin-resistant Staphylococcus aureus (MRSA) were identified as non-Staphylococcus aureus when the sequences were analysed using the bioinformatics software ALEX (www.1928diagnostics.com, Gothenburg, Sweden). Sequencing of the sodA gene of these strains identified them as Staphylococcus argenteus. The collection of MRSA in western Sweden was checked for additional strains of this species. A total of 18 strains of S. argenteus isolated between 2011 and December 2017 were identified.
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| 22. |
- Vandamme, Peter, et al.
(author)
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Achromobacter animicus sp. nov., Achromobacter mucicolens sp. nov., Achromobacter pulmonis sp. nov. and Achromobacter spiritinus sp. nov., from human clinical samples.
- 2013
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In: Systematic and applied microbiology. - : Elsevier BV. - 1618-0984 .- 0723-2020. ; 36:1, s. 1-10
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Journal article (peer-reviewed)abstract
- The phenotypic and genotypic characteristics of fourteen human clinical Achromobacter strains representing four genogroups which were delineated by sequence analysis of nusA, eno, rpoB, gltB, lepA, nuoL and nrdA loci, demonstrated that they represent four novel Achromobacter species. The present study also characterized and provided two additional reference strains for Achromobacter ruhlandii and Achromobacter marplatensis, species for which, thus far, only single strains are publicly available, and further validated the use of 2.1% concatenated nusA, eno, rpoB, gltB, lepA, nuoL and nrdA sequence divergence as a threshold value for species delineation in this genus. Finally, although most Achromobacter species can be distinguished by biochemical characteristics, the present study also highlighted considerable phenotypic intraspecies variability and demonstrated that the type strains may be phenotypically poor representatives of the species. We propose to classify the fourteen human clinical strains as Achromobacter mucicolens sp. nov. (with strain LMG 26685(T) [=CCUG 61961(T)] as the type strain), Achromobacter animicus sp. nov. (with strain LMG 26690(T) [=CCUG 61966(T)] as the type strain), Achromobacter spiritinus sp. nov. (with strain LMG 26692(T) [=CCUG 61968(T)] as the type strain), and Achromobacter pulmonis sp. nov. (with strain LMG 26696(T) [=CCUG 61972(T)] as the type strain).
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| 23. |
- Vandamme, Peter, et al.
(author)
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Classification of Achromobacter genogroups 2, 5, 7 and 14 as Achromobacter insuavis sp. nov., Achromobacter aegrifaciens sp. nov., Achromobacter anxifer sp. nov. and Achromobacter dolens sp. nov., respectively.
- 2013
-
In: Systematic and applied microbiology. - : Elsevier BV. - 1618-0984 .- 0723-2020. ; 36:7, s. 474-482
-
Journal article (peer-reviewed)abstract
- The phenotypic and genotypic characteristics of seventeen Achromobacter strains representing MLST genogroups 2, 5, 7 and 14 were examined. Although genogroup 2 and 14 strains shared a DNA-DNA hybridization level of about 70%, the type strains of both genogroups differed in numerous biochemical characteristics and all genogroup 2 and 14 strains could by distinguished by nitrite reduction, denitrification and growth on acetamide. Given the MLST sequence divergence which identified genogroups 2 and 14 as clearly distinct populations, the availability of nrdA sequence analysis as a single locus identification tool for all Achromobacter species and genogroups, and the differential phenotypic characteristics, we propose to formally classify Achromobacter genogroups 2, 5, 7 and 14 as four novel Achromobacter species for which we propose the names Achromobacter insuavis sp. nov. (with strain LMG 26845(T) [=CCUG 62426(T)] as the type strain), Achromobacter aegrifaciens sp. nov. (with strain LMG 26852(T) [=CCUG 62438(T)] as the type strain), Achromobacter anxifer sp. nov. (with strain LMG 26857(T) [=CCUG 62444(T)] as the type strain), and Achromobacter dolens sp. nov. (with strain LMG 26840(T) [=CCUG 62421(T)] as the type strain).
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| 24. |
- Zamora, L, et al.
(author)
-
Chryseobacterium oncorhynchi sp. nov., isolated from rainbow trout (Oncorhynchus mykiss).
- 2012
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In: Systematic and applied microbiology. - : Elsevier BV. - 1618-0984 .- 0723-2020. ; 35:1, s. 24-9
-
Journal article (peer-reviewed)abstract
- Genotypic and phenotypic analyses were performed on five Gram-negative, catalase and oxidase-positive, rod-shaped bacteria isolated from the gill and liver of four rainbow trout. Studies based on comparative 16S rRNA gene sequence analysis showed that the five new isolates shared 99.8-100% sequence similarity and that they belong to the genus Chryseobacterium. The nearest phylogenetic neighbours of the strain 701B-08(T) were Chryseobacterium ureilyticum F-Fue-04IIIaaaa(T) (99.1% 16S rRNA gene sequence similarity) and Chryseobacterium joosteii LMG 18212(T) (98.6%). DNA-DNA hybridization values between the five isolates were 91-99% and ranged from 2 to 53% between strain 701B-08(T) and the type strains of phylogenetically closely related species of Chryseobacterium. Strain 701B-08(T) had a DNA G+C content of 36.3 mol%, the major fatty acids were iso-C(15:0), iso-C(17:1)ω9c, C(16:1)ω6c and iso-C(17:0) 3-OH and the predominant respiratory quinone was MK-6. The novel isolates were distinguished from related Chryseobacterium species by physiological and biochemical tests. The genotypic and phenotypic properties of the isolates from rainbow trout suggest their classification as representatives of a novel species of the genus Chryseobacterium, for which the name Chryseobacterium oncorhynchi sp. nov. is proposed. The type strain is 701B-08(T) (=CECT 7794(T)=CCUG 60105(T)).
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| 25. |
- Zamora, Leydis, et al.
(author)
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Chryseobacterium viscerum sp. nov., isolated from diseased fish.
- 2012
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In: International journal of systematic and evolutionary microbiology. - : Microbiology Society. - 1466-5034 .- 1466-5026. ; 62:Pt12, s. 2934-40
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Journal article (peer-reviewed)abstract
- A taxonomic study was carried out on five Gram-staining-negative, catalase- and oxidase-positive, rod-shaped bacteria isolated from the gill and liver of five diseased rainbow trout. On the basis of 16S rRNA gene sequence analysis, the trout isolates belonged to the genus Chryseobacterium, exhibiting the highest similarity with Chryseobacterium oncorhynchi 701B-08T (98.9 % sequence similarity), C. ureilyticum F-Fue-04IIIaaaaT (98.6 %), C. indologenes ATCC 29897T (98.3 %), C. jejuense JS17-8T (98.1 %) and C. gleum ATCC 35910T (98.1 %). DNA-DNA hybridization values were 99-100 % among the five isolates and 21 and 57 % between strain 687B-08T, selected as a representative isolate, and the type strains of Chryseobacterium oncorhynchi 701B-08T, C. ureilyticum F-Fue-04IIIaaaaT and other phylogenetic related Chryseobacterium species. The predominant respiratory quinone of strain 687B-08T was MK-6 and the major cellular fatty acids were iso-C15:0, iso-C17:1 ω9c, iso-C17:0 3-OH and C16:1 ω6c. The G+C content of the chromosomal DNA of strain 687B-08T was 38.6 mol%. Based on the phenotypic and genotypic features, the novel bacteria isolated from rainbow trout were significantly different from the related Chryseobacterium species and, therefore, they were identified as representing a novel species of the genus Chryseobacterium, for which the name Chryseobacterium viscerum sp. nov. is proposed. The type strain is 687B-08T (= CECT 7793T = CCUG 60103T).
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| 26. |
- Zamora, L, et al.
(author)
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Flavobacterium oncorhynchi sp. nov., a new species isolated from rainbow trout (Oncorhynchus mykiss).
- 2012
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In: Systematic and applied microbiology. - : Elsevier BV. - 1618-0984 .- 0723-2020. ; 35:2, s. 86-91
-
Journal article (peer-reviewed)abstract
- Eighteen isolates of a Gram-negative, catalase and oxidase-positive, rod-shaped bacterium, recovered from diseased rainbow trout (Oncorhynchus mykiss), were characterized, using a polyphasic taxonomic approach. Studies based on comparative 16S rRNA gene sequence analysis showed that that the eighteen new isolates shared 99.2-100% sequence similarities. Phylogenetic analysis revealed that isolates from trout belonged to the genus Flavobacterium, showing the highest sequence similarities to F. chungangense (98.6%), F. frigidimaris (98.1%), F. hercynium (97.9%) and F. aquidurense (97.8%). DNA-DNA reassociation values between the trout isolates (exemplified by strain 631-08(T)) and five type strains of the most closely related Flavobacterium species exhibited less than 27% similarity. The G+C content of the genomic DNA was 33.0 mol%. The major respiratory quinone was observed to be menaquinone 6 (MK-6) and iso-C(15:0), C(15:0) and C(16:1) ω7c the predominant fatty acids. The polar lipid profile of strain 631-08(T) consisted of phosphatidylethanolamine, unknown aminolipids AL1 and AL3, lipids L1, L2, L3 and L4 and phospholipid PL1. The novel isolates were differentiated from related Flavobacterium species by physiological and biochemical tests. On the basis of the evidence from this polyphasic study, it is proposed that the isolates from rainbow trout be classified as a new species of the genus Flavobacterium, Flavobacterium oncorhynchi sp. nov. The type strain is 631-08(T) (= CECT 7678(T) = CCUG 59446(T)).
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