Peter W. M. Hermans

Strain-specific impact of PsaR of Streptococcus pneumoniae on global gene expression and virulence (2009)

Hendriksen, Wouter T., Bootsma, Hester J., Diepen, Angela Van, Estevão, Silvia, Kuipers, Oscar P., Groot, Ronald De, ...

Previous studies have indicated that PsaR of Streptococcus pneumoniae is a manganese-dependent regulator, negatively affecting the expression of at least seven genes. Here, we extended these...

Site-Specific Contributions of Glutamine-Dependent Regulator GlnR and GlnR-Regulated Genes to Virulence of Streptococcus pneumoniae (2008)

Hendriksen, Wouter T., Kloosterman, Tomas G., Bootsma, Hester J., Estevão, Silvia, Groot, Ronald De, Kuipers, Oscar P., ...

The transcriptional regulator GlnR of Streptococcus pneumoniae is involved in the regulation of glutamine and glutamate metabolism, controlling the expression of the glnRA and glnPQ-zwf operons, as...

CodY of Streptococcus pneumoniae: Link between Nutritional Gene Regulation and Colonization (2008)

Hendriksen, Wouter T., Bootsma, Hester J., Estevão, Silvia, Hoogenboezem, Theo, Jong, Anne De, Groot, Ronald De, ...

CodY is a nutritional regulator mainly involved in amino acid metabolism. It has been extensively studied in Bacillus subtilis and Lactococcus lactis. We investigated the role of CodY in gene...

Development of Genomic Array Footprinting for Identification of Conditionally Essential Genes in Streptococcus pneumoniae (2007)

Bijlsma, Jetta J.E., Burghout, Peter, Kloosterman, Tomas G., Bootsma, Hester J., Jong, Anne De, Hermans, Peter W.M., ...

Streptococcus pneumoniae is a major cause of serious infections such as pneumonia and meningitis in both children and adults worldwide. Here, we describe the development of a high-throughput,...

Regulation of Gene Expression in Streptococcus pneumoniae by Response Regulator 09 Is Strain Dependent (2007)

Kerr, Alison R., Paterson, Gavin K., Blue, Clare E., Bootsma, Hester J., Silva, Nuno, Hendriksen, Wouter T., ...

Recent murine studies have demonstrated that the role of response regulator 09 (RR09) of Streptococcus pneumoniae in virulence is different in different strains. In the present study, we used a...

Search for Genes Essential for Pneumococcal Transformation: the RadA DNA Repair Protein Plays a Role in Genomic Recombination of Donor DNA (2007)

Burghout, Peter, Bootsma, Hester J., Kloosterman, Tomas G., Bijlsma, Jetta J.E., Jongh, Christa E. De, Kuipers, Oscar P., ...

We applied a novel negative selection strategy called genomic array footprinting (GAF) to identify genes required for genetic transformation of the gram-positive bacterium Streptococcus pneumoniae....

Lactococcus lactis GEM particles displaying pneumococcal antigens induce local and systemic immune responses following intranasal immunization (2006)

Selm, Saskia Van, Metselaar, Heidi, Deemter, Mariëlle Van, Post, Eduard, Kanninga, Rolf, Neef, Jolanda, ...

The present work reports the use of non-living non-recombinant bacteria as a delivery system for mucosal vaccination. Antigens are bound to the cell-wall of pretreated Lactococcus lactis, designated...

Regulation of Glutamine and Glutamate Metabolism by GlnR and GlnA in Streptococcus pneumoniae (2006)

Kloosterman, Tomas G., Hendriksen, Wouter T., Bijlsma, Jetta J.E., Bootsma, Hester J., Kok, Jan, ...

Several genes involved in nitrogen metabolism are known to contribute to the virulence of pathogenic bacteria. Here, we studied the function of the nitrogen regulatory protein GlnR in the...

Lactococcus lactis GEM particles displaying pneumococcal antigens induce local and systemic immune responses following intranasal immunization (2006)

Hermans, Peter W.M., Leenhouts, Kees J., Robillard, George T., Selm, Saskia Van, Metselaar, Heidi, Deemter, Mariëlle Van, ...

The present work reports the use of non-living non-recombinant bacteria as a delivery system for mucosal vaccination. Antigens are bound to the cell-wall of pretreated Lactococcus lactis, designated...

Multidrug-Resistant Streptococcus pneumoniae in Poland: Identification of Emerging Clones

Overweg, Karin, Hermans, Peter W. M., Trzcinski, Krzysztof, Sluijter, Marcel, De Groot, Ronald, Hryniewicz, Waleria

Penicillin resistance among Streptococcus pneumoniae isolates has rapidly emerged in Poland during the last decade and has reached prevalence levels of up to 14.4% in 1997. In order to investigate...

Nasopharyngeal Carriage of Penicillin-Resistant Streptococcus pneumoniae among Children with Acute Respiratory Tract Infections in Thailand: a Molecular Epidemiological Survey

Dejsirilert, Surang, Overweg, Karin, Sluijter, Marcel, Saengsuk, Leelawadee, Gratten, Mike, Ezaki, Takayuki, ...

The prevalence of penicillin-resistant Streptococcus pneumoniae in Thailand has dramatically increased over the last decade. During a national survey, which was conducted from 1992 to 1994, 37.2% of...

Molecular Epidemiology of Penicillin-Nonsusceptible Streptococcus pneumoniae among Children in Greece

Bogaert, Debby, Syrogiannopoulos, George A., Grivea, Ioanna N., De Groot, Ronald, Beratis, Nicholas G., Hermans, Peter W. M.

A total of 145 penicillin-nonsusceptible Streptococcus pneumoniae strains were isolated from young carriers in Greece and analyzed by antibiotic susceptibility testing, serotyping, restriction...

Genetic Relatedness within Serotypes of Penicillin-Susceptible Streptococcus pneumoniae Isolates

Overweg, Karin, Bogaert, Debby, Sluijter, Marcel, Yother, Janet, Dankert, Jacob, De Groot, Ronald, ...

The molecular epidemiological characteristics of all Streptococcus pneumoniae strains isolated in a nationwide manner from patients with meningitis in The Netherlands in 1994 were investigated....

Pneumococcal Carriage in Children in The Netherlands: a Molecular Epidemiological Study

Bogaert, Debby, Engelen, Marlene N., Elzenaar, Kees P., Peerbooms, Paul G. H., Coutinho, Roel A., ...

In 1999, Engelen and coworkers investigated colonization in Amsterdam among 259 children attending 16 day-care centers (DCCs) and among 276 children who did not attend day-care centers (NDCCs). A...

Differential Protein Expression in Phenotypic Variants of Streptococcus pneumoniae

Overweg, Karin, Pericone, Chris D., Verhoef, Gerridina G. C., Weiser, Jeffrey N., Meiring, Hugo D., ...

Streptococcus pneumoniae undergoes spontaneous phase variation resulting in opaque and transparent colony forms. Differences in colony opacity correlate with differences in virulence: the transparent...

Inhibitory and Bactericidal Effects of Hydrogen Peroxide Production by Streptococcus pneumoniae on Other Inhabitants of the Upper Respiratory Tract

Pericone, Christopher D., Overweg, Karin, Hermans, Peter W. M., Weiser, Jeffrey N.

An inverse correlation between colonization of the human nasopharynx by Streptococcus pneumoniae and Haemophilus influenzae, both common upper respiratory pathogens, has been reported. Studies were...

Molecular Characterization of Pneumococcal Nasopharynx Isolates Collected from Children during Their First 2 Years of Life

Sluijter, Marcel, Faden, Howard, De Groot, Ronald, Lemmens, Nicole, Goessens, Wil H. F., Van Belkum, Alex, ...

Pneumococcal colonization was studied in 19 children monitored from birth through the age of 2 years. For this purpose, pneumococcal isolates were characterized by capsular typing, restriction...

Host-Pathogen Interaction during Pneumococcal Infection in Patients with Chronic Obstructive Pulmonary Disease

Bogaert, Debby, Van Der Valk, Paul, Ramdin, Reshmi, Sluijter, Marcel, Monninkhof, Evelyn, Hendrix, Ron, ...

Acute exacerbation is a frequent complication of chronic obstructive pulmonary disease (COPD). Recent studies suggested a role for bacteria such as Streptococcus pneumoniae in the development of...

Identification and Characterization of a Novel Outer Membrane Protein (OMP J) of Moraxella catarrhalis That Exists in Two Major Forms

Hays, John P., Van Selm, Saskia, Hoogenboezem, Theo, Estevão, Silvia, Eadie, Kimberly, Van Veelen, Peter, ...

Moraxella catarrhalis is a common commensal of the human respiratory tract that has been associated with a number of disease states, including acute otitis media in children and exacerbations of...

Multidrug-Resistant Streptococcus pneumoniae in Poland: Identification of Emerging Clones

Overweg, Karin, Hermans, Peter W. M., Trzcinski, Krzysztof, Sluijter, Marcel, De Groot, Ronald, Hryniewicz, Waleria

Penicillin resistance among Streptococcus pneumoniae isolates has rapidly emerged in Poland during the last decade and has reached prevalence levels of up to 14.4% in 1997. In order to investigate...

Nasopharyngeal Carriage of Penicillin-Resistant Streptococcus pneumoniae among Children with Acute Respiratory Tract Infections in Thailand: a Molecular Epidemiological Survey

Dejsirilert, Surang, Overweg, Karin, Sluijter, Marcel, Saengsuk, Leelawadee, Gratten, Mike, Ezaki, Takayuki, ...

The prevalence of penicillin-resistant Streptococcus pneumoniae in Thailand has dramatically increased over the last decade. During a national survey, which was conducted from 1992 to 1994, 37.2% of...

Molecular Epidemiology of Penicillin-Nonsusceptible Streptococcus pneumoniae among Children in Greece

Bogaert, Debby, Syrogiannopoulos, George A., Grivea, Ioanna N., De Groot, Ronald, Beratis, Nicholas G., Hermans, Peter W. M.

A total of 145 penicillin-nonsusceptible Streptococcus pneumoniae strains were isolated from young carriers in Greece and analyzed by antibiotic susceptibility testing, serotyping, restriction...

Genetic Relatedness within Serotypes of Penicillin-Susceptible Streptococcus pneumoniae Isolates

Overweg, Karin, Bogaert, Debby, Sluijter, Marcel, Yother, Janet, Dankert, Jacob, De Groot, Ronald, ...

The molecular epidemiological characteristics of all Streptococcus pneumoniae strains isolated in a nationwide manner from patients with meningitis in The Netherlands in 1994 were investigated....

Pneumococcal Carriage in Children in The Netherlands: a Molecular Epidemiological Study

Bogaert, Debby, Engelen, Marlene N., Elzenaar, Kees P., Peerbooms, Paul G. H., Coutinho, Roel A., ...

In 1999, Engelen and coworkers investigated colonization in Amsterdam among 259 children attending 16 day-care centers (DCCs) and among 276 children who did not attend day-care centers (NDCCs). A...

Differential Protein Expression in Phenotypic Variants of Streptococcus pneumoniae

Overweg, Karin, Pericone, Chris D., Verhoef, Gerridina G. C., Weiser, Jeffrey N., Meiring, Hugo D., ...

Streptococcus pneumoniae undergoes spontaneous phase variation resulting in opaque and transparent colony forms. Differences in colony opacity correlate with differences in virulence: the transparent...

Inhibitory and Bactericidal Effects of Hydrogen Peroxide Production by Streptococcus pneumoniae on Other Inhabitants of the Upper Respiratory Tract

Pericone, Christopher D., Overweg, Karin, Hermans, Peter W. M., Weiser, Jeffrey N.

An inverse correlation between colonization of the human nasopharynx by Streptococcus pneumoniae and Haemophilus influenzae, both common upper respiratory pathogens, has been reported. Studies were...

Molecular Characterization of Pneumococcal Nasopharynx Isolates Collected from Children during Their First 2 Years of Life

Sluijter, Marcel, Faden, Howard, De Groot, Ronald, Lemmens, Nicole, Goessens, Wil H. F., Van Belkum, Alex, ...

Pneumococcal colonization was studied in 19 children monitored from birth through the age of 2 years. For this purpose, pneumococcal isolates were characterized by capsular typing, restriction...

Host-Pathogen Interaction during Pneumococcal Infection in Patients with Chronic Obstructive Pulmonary Disease

Bogaert, Debby, Van Der Valk, Paul, Ramdin, Reshmi, Sluijter, Marcel, Monninkhof, Evelyn, Hendrix, Ron, ...

Acute exacerbation is a frequent complication of chronic obstructive pulmonary disease (COPD). Recent studies suggested a role for bacteria such as Streptococcus pneumoniae in the development of...

Identification and Characterization of a Novel Outer Membrane Protein (OMP J) of Moraxella catarrhalis That Exists in Two Major Forms

Hays, John P., Van Selm, Saskia, Hoogenboezem, Theo, Estevão, Silvia, Eadie, Kimberly, Van Veelen, Peter, ...

Moraxella catarrhalis is a common commensal of the human respiratory tract that has been associated with a number of disease states, including acute otitis media in children and exacerbations of...

Regulation of Gene Expression in Streptococcus pneumoniae by Response Regulator 09 Is Strain Dependent▿ †

Hendriksen, Wouter T., Silva, Nuno, Bootsma, Hester J., Blue, Clare E., Paterson, Gavin K., Kerr, Alison R., ...

Recent murine studies have demonstrated that the role of response regulator 09 (RR09) of Streptococcus pneumoniae in virulence is different in different strains. In the present study, we used a...

Development of Genomic Array Footprinting for Identification of Conditionally Essential Genes in Streptococcus pneumoniae▿ †

Bijlsma, Jetta J. E., Burghout, Peter, Kloosterman, Tomas G., Bootsma, Hester J., De Jong, Anne, Hermans, Peter W. M., ...

Streptococcus pneumoniae is a major cause of serious infections such as pneumonia and meningitis in both children and adults worldwide. Here, we describe the development of a high-throughput,...

Search for Genes Essential for Pneumococcal Transformation: the RadA DNA Repair Protein Plays a Role in Genomic Recombination of Donor DNA▿

Burghout, Peter, Bootsma, Hester J., Kloosterman, Tomas G., Bijlsma, Jetta J. E., De Jongh, Christa E., Kuipers, Oscar P., ...

We applied a novel negative selection strategy called genomic array footprinting (GAF) to identify genes required for genetic transformation of the gram-positive bacterium Streptococcus pneumoniae....

Analysis of the In Vitro Transcriptional Response of Human Pharyngeal Epithelial Cells to Adherent Streptococcus pneumoniae: Evidence for a Distinct Response to Encapsulated Strains▿ †

Bootsma, Hester J., Egmont-Petersen, Michael, Hermans, Peter W. M.

Infection of the human host by Streptococcus pneumoniae begins with colonization of the nasopharynx, which is mediated by the adherence of bacteria to the respiratory epithelium. Several studies have...

CodY of Streptococcus pneumoniae: Link between Nutritional Gene Regulation and Colonization▿

Hendriksen, Wouter T., Bootsma, Hester J., Estevão, Silvia, Hoogenboezem, Theo, De Jong, Anne, De Groot, Ronald, ...

CodY is a nutritional regulator mainly involved in amino acid metabolism. It has been extensively studied in Bacillus subtilis and Lactococcus lactis. We investigated the role of CodY in gene...

Site-Specific Contributions of Glutamine-Dependent Regulator GlnR and GlnR-Regulated Genes to Virulence of Streptococcus pneumoniae▿

Hendriksen, Wouter T., Kloosterman, Tomas G., Bootsma, Hester J., Estevão, Silvia, De Groot, Ronald, Kuipers, Oscar P., ...

The transcriptional regulator GlnR of Streptococcus pneumoniae is involved in the regulation of glutamine and glutamate metabolism, controlling the expression of the glnRA and glnPQ-zwf operons, as...