Delphine Beeckman - Academia.edu (original) (raw)
Papers by Delphine Beeckman
Frontiers in artificial intelligence, Jun 19, 2023
Access microbiology, May 27, 2022
... Record Details. Record ID, 902100. Record Type, conference. Author, Katelijn Schautteet [8020... more ... Record Details. Record ID, 902100. Record Type, conference. Author, Katelijn Schautteet [802000077535] - Ghent University Katelijn.Schautteet@UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; ...
... Record ID, 1036053. Record Type, conference. Author, Caroline Van Droogenbroeck [801002092530... more ... Record ID, 1036053. Record Type, conference. Author, Caroline Van Droogenbroeck [801002092530] - Ghent University Caroline.VanDroogenbroeck@UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; ...
Veterinary Research, Jul 10, 2007
The effect of ovotransferrin (ovoTF), human lactoferrin (hLF) and bovine lactoferrin (bLF) on the... more The effect of ovotransferrin (ovoTF), human lactoferrin (hLF) and bovine lactoferrin (bLF) on the obligate intracellular pathogen Chlamydophila (Cp.) psittaci was evaluated using a model of Buffalo Green Monkey kidney (BGM) cells and HD11 chicken macrophages as artificial hosts. Firstly, the effect of transferrins on the infectivity of the bacteria was evaluated. Pre-incubation of Cp. psittaci with 0.5 to 5 mg/mL ovoTF prior to infecting BGM cells significantly lowered the infection rate (P < 0.05). For both lactoferrins, the infection rate could only be reduced with 5 mg/mL, albeit not significantly as compared to the infection rate created by the untreated bacteria. Secondly, transferrins were tested for their ability to influence bacterial adhesion and entry in HD11 cells. Maximal non-cytotoxic and non-bactericidal concentrations of 0.05 mg/mL ovoTF and 0.5 mg/mL hLF and bLF were used. Overall, ovoTF was more effective than human and bovine LF in inhibiting bacterial irreversible attachment and cell entry and the latter was accompanied by a dose-dependent reduction of actin recruitment at the bacterial entry site. However, once bacteria had entered HD11 cells, transferrins had apparently no effect on intracellular replication. The present findings suggest a possible role for transferrins and especially ovoTF, in preventing avian Cp. psittaci infections. ovotransferrin / lactoferrin / Chlamydia / Chlamydophila psittaci
BMC Genomics, Mar 6, 2021
Background: Chlamydia abortus and Chlamydia psittaci are important pathogens of livestock and avi... more Background: Chlamydia abortus and Chlamydia psittaci are important pathogens of livestock and avian species, respectively. While C. abortus is recognized as descended from C. psittaci species, there is emerging evidence of strains that are intermediary between the two species, suggesting they are recent evolutionary ancestors of C. abortus. Such strains include C. psittaci strain 84/2334 that was isolated from a parrot. Our aim was to classify this strain by sequencing its genome and explore its evolutionary relationship to both C. abortus and C. psittaci. Results: In this study, methods based on multi-locus sequence typing (MLST) of seven housekeeping genes and on typing of five species discriminant proteins showed that strain 84/2334 clustered with C. abortus species. Furthermore, whole genome de novo sequencing of the strain revealed greater similarity to C. abortus in terms of GC content, while 16S rRNA and whole genome phylogenetic analysis, as well as network and recombination analysis showed that the strain clusters more closely with C. abortus strains. The analysis also suggested a closer evolutionary relationship between this strain and the major C. abortus clade, than to two other intermediary avian C. abortus strains or C. psittaci strains. Molecular analyses of genes (polymorphic membrane protein and transmembrane head protein genes) and loci (plasticity zone), found in key virulence-associated regions that exhibit greatest diversity within and between chlamydial species, reveal greater diversity than present in sequenced C. abortus genomes as well as similar features to both C. abortus and C. psittaci species. The strain also possesses an extrachromosomal plasmid, as found in most C. psittaci species but absent from all sequenced classical C. abortus strains.
... Record Details. Record ID, 376805. Record Type, conference. Author, Delphine Sylvie Anne Beec... more ... Record Details. Record ID, 376805. Record Type, conference. Author, Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; Patric Van Oostveldt [801000231039] - Ghent University Patrick.VanOostveldt@UGent.be; ...
Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eu... more Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eukaryotic cells. It has been proven that most of them possess a type III secretion system (T3SS) allowing them to transfer effector molecules in the host cell. We examined the existence of a T3SS in Chlamydophila psittaci by studying the expression of three essential structural proteins SctW, SctC, and SctN, and one putative effector protein IncA. Immunofluorescence assays showed SctW and IncA to be associated with the bacteria and the inclusion membrane, while SctC and SctN were only localized to the bacteria itself. Immuno electron microscopy could confirm these results for SctW, IncA, and SctC. Unfortunately, SctN was not investigated with this technique. Additionally, we sequenced 14 full-length T3S genes (scc1, sctW, sctJ, sctL, sctR, sctS, scc2, copD1, sctN, sctQ, sctC, incA, ca037, and cadd) and examined the transcription of 26 Cp. psittaci T3S genes namely cluster 1 (scc1, sctW, sctV, sctU), cluster 2 (sctJ, sctL, sctR, sctS, sctT, scc2, copB1, copD1), cluster 3 (sctD, sctN, ca037, sctQ, pkn5, sctC) and non-clustered genes (incA, incC, scc3, copD2, cap1, tarp, ca530, cadd). The gene expression study indicated the T3S structural protein encoding genes to be transcribed from mid-cycle (12-18 h post infection (p.i.)) on. Genes encoding effector proteins and putative T3S related proteins were expressed early (1.5 h-8 h p.i.) or late (>24 h p.i.) during the developmental cycle. We hereby provided evidence for the existence of a T3SS and possible effectors in avian Cp. psittaci. Type III secretion / Chlamydia / Chlamydophila psittaci
… Workshop, 8, Abstracts, 2010
Additional file 8: Fig. S6. Summary of Gubbins recombination analysis including avian C. abortus ... more Additional file 8: Fig. S6. Summary of Gubbins recombination analysis including avian C. abortus strains 15-59d/3 and 15-70d/24. The red blocks represent recombination events occurring on an internal branch of the phylogenetic tree, which are shared by several strains by common descent. The blue blocks indicate recombination events occurring on terminal branches of the phylogenetic tree, which are unique to a specific strain. The parameters used for the run are those described in Fig. 4.
Additional file 6: Fig. S4. Whole genome phylogenetic analysis. Phylogenetic tree of a whole geno... more Additional file 6: Fig. S4. Whole genome phylogenetic analysis. Phylogenetic tree of a whole genome sequence MAFFT alignment of the C. abortus (Cab) and C. psittaci (Cps) strains shown in Table 2, and C. buteonis strain RSHA. The consensus tree was estimated in IQ-Tree by Maximum Likelihood using a TVM + F + R2 substitution and rate heterogeneity model, according to BIC model selection, and 100 non-parametric bootstrap replicates. The tree is midpoint rooted and bootstrap support is indicated by the number at the node. The scale bar indicates the expected substitutions per site. Genotypes are given in square brackets. The tree was prepared in Dendroscope. Strain 84/2334 is in bold and red font. Classical and avian C. abortus strains are in blue and green fonts, respectively.
Additional file 7: Fig. S5. Whole genome NeighborNet network analysis. Phylogenetic network of a ... more Additional file 7: Fig. S5. Whole genome NeighborNet network analysis. Phylogenetic network of a whole genome sequence alignment of the C. abortus (Cab) and C. psittaci (Cps) strains shown in Table 2, using the NeighborNet distances transformation (Ordinary Least Squares variance and Lambda Frac of 1.0) and EqualAngle splits transformation. The scale bar indicates the expected substitutions per site. Genotypes of C. psittaci and avian C. abortus strains are indicated in brackets. The figure was generated using SplitsTree4. Strain 84/2334 is in bold and red font.
Additional file 3: Fig. S2. Phylogenetic tree of a 16S rRNA gene alignment of strain 84/2334 and ... more Additional file 3: Fig. S2. Phylogenetic tree of a 16S rRNA gene alignment of strain 84/2334 and other Chlamydiaceae species. The consensus tree for the 1470 bp alignment was estimated in TOPALi by Neighbour Joining using a F84 + G substitution and rate heterogeneity model and 100 non-parametric bootstrap replicates. The tree is midpoint rooted and bootstrap support is indicated by the number at the node. The scale bar indicates the expected substitutions per site. Genotypes are given in square brackets. The tree was prepared in Dendroscope. Strain 84/2334 is in bold and red font.
Additional file 11: Fig. S9. Polymorphic membrane protein family phylogenies. Consensus trees for... more Additional file 11: Fig. S9. Polymorphic membrane protein family phylogenies. Consensus trees for singleton PmpA, PmpB, PmpD and PmpH family members (A), for the PmpE family members (B) and PmpG family members (C) for strain 84/2334 and the C. abortus and C. psittaci strains/genotypes shown in Table 2 were estimated in IQ-Tree by Maximum Likelihood using substitution and rate heterogeneity models JTTDCMut + F + I + G4, JTT + F + R3 and JTT + F + R5, respectively, according to BIC model selection, and 100 non-parametric bootstrap replicates. The trees were midpoint rooted and bootstrap support is indicated by the number at the node (only values greater than 70 are shown). The scale bar indicates the expected substitutions per site. The trees were prepared in Dendroscope. Strain 84/2334 is in bold and red font. Classical and avian C. abortus strains are in blue and green fonts, respectively.
Nowadays, one lift among the fundamental equipments at auto-repair must withstand the heavy weigh... more Nowadays, one lift among the fundamental equipments at auto-repair must withstand the heavy weight of car. Therefore, the strong lift which is easy to make repairs on cars is the indispensible equipment. In this study, three kinds of lifts are modelled and the simulation analysis is carried out with the finite element analysis program of ANSYS. The durability of lifts due to each configuration can be
Microscopy Research and Technique, 2009
Traditionally, the amount of infective chlamydiae in a given sample is determined by inoculating ... more Traditionally, the amount of infective chlamydiae in a given sample is determined by inoculating dilution series into cell cultures and physically counting chlamydial inclusions. This approach is time consuming, tedious, and error prone, mainly when dealing with high titers. Therefore, this paper describes a largely automated technique that was developed to standardize the determination of chlamydial load in vitro. Cells are fixed at 36 h post-inoculation and bacteria visualized using standard immunological detection methods. Consequently, for 81 microscopic fields, an image is recorded at the interpolated focal plane. These images are then automatically processed using an ImageJ plugin and the obtained results are imported into Excel to determine the number of inclusion forming units per mL in the sample. The main advantage of this technique is that no or minimal sample dilution is required, thus minimizing dilution errors. In addition, this technique was employed during the early, middle and late growth stages of the chlamydial developmental cycle and results correlated well (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01) with 16S rRNA values from previous experiments, thereby proving its suitability to follow chlamydial growth in vitro. The method described is highly suitable for high throughput titration of cell culture inoculated samples and assessment of possible antichlamydial effects of novel compounds throughout the chlamydial growth cycle.
Copyright It is not permitted to download or to forward/distribute the text or part of it without... more Copyright It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content licence (like
... UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent UniversityDelphine.Beeckman@UG... more ... UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent UniversityDelphine.Beeckman@UGent.be; Marian Carlon; S Van Acker; Koen Chiers [801001013810] - Ghent University Koen.Chiers@UGent.be; Eric Cox ...
Frontiers in artificial intelligence, Jun 19, 2023
Access microbiology, May 27, 2022
... Record Details. Record ID, 902100. Record Type, conference. Author, Katelijn Schautteet [8020... more ... Record Details. Record ID, 902100. Record Type, conference. Author, Katelijn Schautteet [802000077535] - Ghent University Katelijn.Schautteet@UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; ...
... Record ID, 1036053. Record Type, conference. Author, Caroline Van Droogenbroeck [801002092530... more ... Record ID, 1036053. Record Type, conference. Author, Caroline Van Droogenbroeck [801002092530] - Ghent University Caroline.VanDroogenbroeck@UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; ...
Veterinary Research, Jul 10, 2007
The effect of ovotransferrin (ovoTF), human lactoferrin (hLF) and bovine lactoferrin (bLF) on the... more The effect of ovotransferrin (ovoTF), human lactoferrin (hLF) and bovine lactoferrin (bLF) on the obligate intracellular pathogen Chlamydophila (Cp.) psittaci was evaluated using a model of Buffalo Green Monkey kidney (BGM) cells and HD11 chicken macrophages as artificial hosts. Firstly, the effect of transferrins on the infectivity of the bacteria was evaluated. Pre-incubation of Cp. psittaci with 0.5 to 5 mg/mL ovoTF prior to infecting BGM cells significantly lowered the infection rate (P < 0.05). For both lactoferrins, the infection rate could only be reduced with 5 mg/mL, albeit not significantly as compared to the infection rate created by the untreated bacteria. Secondly, transferrins were tested for their ability to influence bacterial adhesion and entry in HD11 cells. Maximal non-cytotoxic and non-bactericidal concentrations of 0.05 mg/mL ovoTF and 0.5 mg/mL hLF and bLF were used. Overall, ovoTF was more effective than human and bovine LF in inhibiting bacterial irreversible attachment and cell entry and the latter was accompanied by a dose-dependent reduction of actin recruitment at the bacterial entry site. However, once bacteria had entered HD11 cells, transferrins had apparently no effect on intracellular replication. The present findings suggest a possible role for transferrins and especially ovoTF, in preventing avian Cp. psittaci infections. ovotransferrin / lactoferrin / Chlamydia / Chlamydophila psittaci
BMC Genomics, Mar 6, 2021
Background: Chlamydia abortus and Chlamydia psittaci are important pathogens of livestock and avi... more Background: Chlamydia abortus and Chlamydia psittaci are important pathogens of livestock and avian species, respectively. While C. abortus is recognized as descended from C. psittaci species, there is emerging evidence of strains that are intermediary between the two species, suggesting they are recent evolutionary ancestors of C. abortus. Such strains include C. psittaci strain 84/2334 that was isolated from a parrot. Our aim was to classify this strain by sequencing its genome and explore its evolutionary relationship to both C. abortus and C. psittaci. Results: In this study, methods based on multi-locus sequence typing (MLST) of seven housekeeping genes and on typing of five species discriminant proteins showed that strain 84/2334 clustered with C. abortus species. Furthermore, whole genome de novo sequencing of the strain revealed greater similarity to C. abortus in terms of GC content, while 16S rRNA and whole genome phylogenetic analysis, as well as network and recombination analysis showed that the strain clusters more closely with C. abortus strains. The analysis also suggested a closer evolutionary relationship between this strain and the major C. abortus clade, than to two other intermediary avian C. abortus strains or C. psittaci strains. Molecular analyses of genes (polymorphic membrane protein and transmembrane head protein genes) and loci (plasticity zone), found in key virulence-associated regions that exhibit greatest diversity within and between chlamydial species, reveal greater diversity than present in sequenced C. abortus genomes as well as similar features to both C. abortus and C. psittaci species. The strain also possesses an extrachromosomal plasmid, as found in most C. psittaci species but absent from all sequenced classical C. abortus strains.
... Record Details. Record ID, 376805. Record Type, conference. Author, Delphine Sylvie Anne Beec... more ... Record Details. Record ID, 376805. Record Type, conference. Author, Delphine Sylvie Anne Beeckman [801002018970] - Ghent University Delphine.Beeckman@UGent.be; Patric Van Oostveldt [801000231039] - Ghent University Patrick.VanOostveldt@UGent.be; ...
Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eu... more Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eukaryotic cells. It has been proven that most of them possess a type III secretion system (T3SS) allowing them to transfer effector molecules in the host cell. We examined the existence of a T3SS in Chlamydophila psittaci by studying the expression of three essential structural proteins SctW, SctC, and SctN, and one putative effector protein IncA. Immunofluorescence assays showed SctW and IncA to be associated with the bacteria and the inclusion membrane, while SctC and SctN were only localized to the bacteria itself. Immuno electron microscopy could confirm these results for SctW, IncA, and SctC. Unfortunately, SctN was not investigated with this technique. Additionally, we sequenced 14 full-length T3S genes (scc1, sctW, sctJ, sctL, sctR, sctS, scc2, copD1, sctN, sctQ, sctC, incA, ca037, and cadd) and examined the transcription of 26 Cp. psittaci T3S genes namely cluster 1 (scc1, sctW, sctV, sctU), cluster 2 (sctJ, sctL, sctR, sctS, sctT, scc2, copB1, copD1), cluster 3 (sctD, sctN, ca037, sctQ, pkn5, sctC) and non-clustered genes (incA, incC, scc3, copD2, cap1, tarp, ca530, cadd). The gene expression study indicated the T3S structural protein encoding genes to be transcribed from mid-cycle (12-18 h post infection (p.i.)) on. Genes encoding effector proteins and putative T3S related proteins were expressed early (1.5 h-8 h p.i.) or late (>24 h p.i.) during the developmental cycle. We hereby provided evidence for the existence of a T3SS and possible effectors in avian Cp. psittaci. Type III secretion / Chlamydia / Chlamydophila psittaci
… Workshop, 8, Abstracts, 2010
Additional file 8: Fig. S6. Summary of Gubbins recombination analysis including avian C. abortus ... more Additional file 8: Fig. S6. Summary of Gubbins recombination analysis including avian C. abortus strains 15-59d/3 and 15-70d/24. The red blocks represent recombination events occurring on an internal branch of the phylogenetic tree, which are shared by several strains by common descent. The blue blocks indicate recombination events occurring on terminal branches of the phylogenetic tree, which are unique to a specific strain. The parameters used for the run are those described in Fig. 4.
Additional file 6: Fig. S4. Whole genome phylogenetic analysis. Phylogenetic tree of a whole geno... more Additional file 6: Fig. S4. Whole genome phylogenetic analysis. Phylogenetic tree of a whole genome sequence MAFFT alignment of the C. abortus (Cab) and C. psittaci (Cps) strains shown in Table 2, and C. buteonis strain RSHA. The consensus tree was estimated in IQ-Tree by Maximum Likelihood using a TVM + F + R2 substitution and rate heterogeneity model, according to BIC model selection, and 100 non-parametric bootstrap replicates. The tree is midpoint rooted and bootstrap support is indicated by the number at the node. The scale bar indicates the expected substitutions per site. Genotypes are given in square brackets. The tree was prepared in Dendroscope. Strain 84/2334 is in bold and red font. Classical and avian C. abortus strains are in blue and green fonts, respectively.
Additional file 7: Fig. S5. Whole genome NeighborNet network analysis. Phylogenetic network of a ... more Additional file 7: Fig. S5. Whole genome NeighborNet network analysis. Phylogenetic network of a whole genome sequence alignment of the C. abortus (Cab) and C. psittaci (Cps) strains shown in Table 2, using the NeighborNet distances transformation (Ordinary Least Squares variance and Lambda Frac of 1.0) and EqualAngle splits transformation. The scale bar indicates the expected substitutions per site. Genotypes of C. psittaci and avian C. abortus strains are indicated in brackets. The figure was generated using SplitsTree4. Strain 84/2334 is in bold and red font.
Additional file 3: Fig. S2. Phylogenetic tree of a 16S rRNA gene alignment of strain 84/2334 and ... more Additional file 3: Fig. S2. Phylogenetic tree of a 16S rRNA gene alignment of strain 84/2334 and other Chlamydiaceae species. The consensus tree for the 1470 bp alignment was estimated in TOPALi by Neighbour Joining using a F84 + G substitution and rate heterogeneity model and 100 non-parametric bootstrap replicates. The tree is midpoint rooted and bootstrap support is indicated by the number at the node. The scale bar indicates the expected substitutions per site. Genotypes are given in square brackets. The tree was prepared in Dendroscope. Strain 84/2334 is in bold and red font.
Additional file 11: Fig. S9. Polymorphic membrane protein family phylogenies. Consensus trees for... more Additional file 11: Fig. S9. Polymorphic membrane protein family phylogenies. Consensus trees for singleton PmpA, PmpB, PmpD and PmpH family members (A), for the PmpE family members (B) and PmpG family members (C) for strain 84/2334 and the C. abortus and C. psittaci strains/genotypes shown in Table 2 were estimated in IQ-Tree by Maximum Likelihood using substitution and rate heterogeneity models JTTDCMut + F + I + G4, JTT + F + R3 and JTT + F + R5, respectively, according to BIC model selection, and 100 non-parametric bootstrap replicates. The trees were midpoint rooted and bootstrap support is indicated by the number at the node (only values greater than 70 are shown). The scale bar indicates the expected substitutions per site. The trees were prepared in Dendroscope. Strain 84/2334 is in bold and red font. Classical and avian C. abortus strains are in blue and green fonts, respectively.
Nowadays, one lift among the fundamental equipments at auto-repair must withstand the heavy weigh... more Nowadays, one lift among the fundamental equipments at auto-repair must withstand the heavy weight of car. Therefore, the strong lift which is easy to make repairs on cars is the indispensible equipment. In this study, three kinds of lifts are modelled and the simulation analysis is carried out with the finite element analysis program of ANSYS. The durability of lifts due to each configuration can be
Microscopy Research and Technique, 2009
Traditionally, the amount of infective chlamydiae in a given sample is determined by inoculating ... more Traditionally, the amount of infective chlamydiae in a given sample is determined by inoculating dilution series into cell cultures and physically counting chlamydial inclusions. This approach is time consuming, tedious, and error prone, mainly when dealing with high titers. Therefore, this paper describes a largely automated technique that was developed to standardize the determination of chlamydial load in vitro. Cells are fixed at 36 h post-inoculation and bacteria visualized using standard immunological detection methods. Consequently, for 81 microscopic fields, an image is recorded at the interpolated focal plane. These images are then automatically processed using an ImageJ plugin and the obtained results are imported into Excel to determine the number of inclusion forming units per mL in the sample. The main advantage of this technique is that no or minimal sample dilution is required, thus minimizing dilution errors. In addition, this technique was employed during the early, middle and late growth stages of the chlamydial developmental cycle and results correlated well (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01) with 16S rRNA values from previous experiments, thereby proving its suitability to follow chlamydial growth in vitro. The method described is highly suitable for high throughput titration of cell culture inoculated samples and assessment of possible antichlamydial effects of novel compounds throughout the chlamydial growth cycle.
Copyright It is not permitted to download or to forward/distribute the text or part of it without... more Copyright It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content licence (like
... UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent UniversityDelphine.Beeckman@UG... more ... UGent.be; Delphine Sylvie Anne Beeckman [801002018970] - Ghent UniversityDelphine.Beeckman@UGent.be; Marian Carlon; S Van Acker; Koen Chiers [801001013810] - Ghent University Koen.Chiers@UGent.be; Eric Cox ...