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Pneumococcus

Research Lines

Content with Investigacion Genética Bacteriana .

Bacterial Genetics

Our group has been studying for more than 30 years the mechanisms of antibiotic resistance in Streptococcus pneumoniae (Spn). Our objectives are to understand the molecular basis of antimicrobial action, to search for new targets of action and new compounds. Seconeolitsine (SCN) is one of these new compounds targeting topoisomerase I (Topo I). As for the search for new targets, our research has focused in recent years on the factors that organize the topology of the chromosome, allowing optimal compaction (about 1000-fold) to harmonize its replication, chromosome segregation and gene expression. This compaction is mediated both by the level of DNA supercoiling (Sc) and by association with nucleoid-binding proteins (NAPs). The level of Sc depends mainly on the enzymatic activities of their DNA topoisomerases, reaching a homeostatic equilibrium by the opposite activities of the topoisomerases that relax DNA (Topo I and Topo IV), and of gyrase, which introduces negative Sc. Our group has characterized the three Spn topoisomerases and two NAPs: HU and SatR. In addition, the availability of antimicrobials that inhibit each of the Spn topoisomerases has allowed us to analyze their transcriptome under conditions of local or global change of the Sc level and to define gene domains of coordinated transcription and similar functions. Fluoroquinolones, which inhibit Topo IV and gyrase, produce local changes in Sc that induce alterations in 6% of the transcriptome, altering metabolic pathways that originate an increase in reactive oxygen species (ROS) that contribute to lethality, in accordance with the general mechanism of bactericidal antibiotics. On the other hand, the induction of global changes in Sc by novobiocin (NOV, gyrase inhibitor), or by SCN (Topo I inhibitor), has allowed us to define topological domains. Global changes in Sc include the regulation of topoisomerase genes: its decrease activates the transcription of gyrase genes (gyrA, gyrB) and inhibits those of Topo IV (parEC) and Topo I (topA); the increase in Sc regulates the expression of topA. Decreased Sc affects 37% of the genome, with >68% of genes clustered in 15 domains. Increased Sc affects 10% of the genome, with 25% of the genes clustered in 12 domains. The AT content in the genome correlates with the domains, being higher in UP domains than in DOWN domains. The genes in the different domains have common functional characteristics, indicating that they have been subjected to topological selective pressure to determine the location of genes involved in metabolism, virulence and competition. 

The current objectives of the group are:
1.    Identification of factors that stabilize chromosome topology: NAPs, ncRNAs, intra-chromosomal interactions.
2.    Regulation of transcription in response to topological stress: in vivo localization of DNA topoisomerases, RNA polymerase and NAPs.
3.    Topo I as a new antimicrobial target and action of SCN. 
4.    Design of antisense RNAs and use of the CRISPR system as new antibacterial agents.

Research projects

Content with Investigacion Genética Bacteriana .

1) Project Title: Interaction Between DNA Supercoiling and Transcription in the Human Pathogen  Streptococcus pneumoniae

Principal Investigator:   Adela González de la Campa  
Funding Entity:   Ministry of Science and Innovation, State Research Agency (Call for "R&D&I Projects" 2020 – "Research Challenges" and "Knowledge Generation" Modalities).  
Reference:   PID2021-124738OB-100.  
Duration:   2022-2025.  
Funding Amount:   €108,900.
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2) Project Title:   Study of the Factors Organizing the Chromosome of  Streptococcus pneumoniae: New Antibiotic Targets and Resistance Mechanisms.

Principal Investigator:   Adela González de la Campa  
Funding Entity:   Ministry of Economy, Industry, and Competitiveness. State Research Agency.  
Reference:   BIO2017-82951-R.  
Duration:   2018-2020.  
Funding Amount:   €169,400.  

3) Project Title:   Role of DNA Topoisomerases and Nucleoid-Associated Proteins in the Chromosome Organization of  Streptococcus pneumoniae: Response to Antibiotics and Virulence.  

Principal Investigator:   Adela González de la Campa  
Funding Entity:   Ministry of Economy and Competitiveness. Secretariat of State for Research, Development, and Innovation.  
Reference:   BIO2014-55462.  
Duration:   2015-2017.  
Funding Amount:   €193,600.  

4) Project Title:   The Control of Supercoiling Level in  Streptococcus pneumoniae  as an Antimicrobial Target.  

Principal Investigator:   Adela González de la Campa  
Funding Entity:   Ministry of Economy and Competitiveness. Secretariat of State for Research, Development, and Innovation.  
Reference:   BIO2011-25343.  
Duration:   2012-2015.  
Funding Amount:   €209,000.  

5) Project Title:   Role of Small Non-Coding RNAs in the Pathogenicity of  Streptococcus pneumoniae.   

Principal Investigator:   Mónica Amblar Esteban  
Funding Entity:   Ministry of Economy and Competitiveness. Strategic Health Action (AES).  
Reference:   PI11/00656.  
Duration:   2012-2015.  
Funding Amount:   €198,714.
 

Publications

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Suppression of CD4+ T lymphocyte activation in vitro and experimental encephalomyelitis in vivo by the phosphatidyl inositol 3-kinase inhibitor PIK-75.

3. Acosta YY, Montes-Casado M, Aragoneses-Fenoll L, Dianzani U, Portoles P, Rojo JM. Suppression of CD4+ T lymphocyte activation in vitro and experimental encephalomyelitis in vivo by the phosphatidyl inositol 3-kinase inhibitor PIK-75. Int. J. Immunopathol. Pharmacol. 2014 Jan-Mar;27(1):53-67.

PUBMED DOI

Horizontal gene transmission of the cfr gene to MRSA and Enterococcus: role of Staphylococcus epidermidis as a reservoir and alternative pathway for the spread of linezolid resistance.

Horizontal gene transmission of the cfr gene to MRSA and Enterococcus: role of Staphylococcus epidermidis as a reservoir and alternative pathway for the spread of linezolid resistance. Cafini F, Nguyen le TT, Higashide M, Román F, Prieto J, Morikawa K. J Antimicrob Chemother. 2016 Mar;71(3):587-92.

PUBMED

Focusing on Gordonia Infections: Distribution, Antimicrobial Susceptibilities and Phylogeny

Pino-Rosa S, Medina-Pascual MJ, Carrasco G, Garrido N, Villalón P, Valiente M, Valdezate S. (2023). Focusing on Gordonia Infections: Distribution, Antimicrobial Susceptibilities and Phylogeny. Antibiotics (Basel). 26;12(11):1568

PUBMED DOI

Antibody responses to chimeric peptides derived from parasite antigens in mice and other animal species.

Orbegozo-Medina RA, Martínez-Sernández V, Folgueira I, Mezo M, González-Warleta M, Perteguer MJ, Romarís F, Leiro JM, Ubeira FM. Antibody responses to chimeric peptides derived from parasite antigens in mice and other animal species. Mol Immunol. 2018 Dec 17;106:1-11.

PUBMED DOI

Role of PatAB transporter in efflux of levofloxacin in Streptococcus pneumoniae

Amblar M, Zaballos A, de la Campa AG. Antibiotics. 2022; 17:1837.

PUBMED DOI

Role of Toll-like receptor 4 in intravascular hemolisis-mediated injury

Vázquez-Carballo C, Herencia C, Guerrero-Hue M, García-Caballero C, Rayego-Mateos S, Morgado-Pascual JL, Opazo-Rios L, González-Guerrero C, Vallejo-Mudarra M, Cortegano I, Gaspar ML, de Andrés B, Egido J, Moreno JA. J Pathol. 2022 Nov; 258(3): 236–249.

PUBMED DOI

Carbapenemase-Producing Klebsiella pneumoniae in COVID-19 Intensive Care Patients: Identification of IncL-VIM-1 Plasmid in Previously Non-Predominant Sequence Types.

3. Carbapenemase-Producing Klebsiella pneumoniae in COVID-19 Intensive Care Patients: Identification of IncL-VIM-1 Plasmid in Previously Non-Predominant Sequence Types. Autores: Cañada-García JE, Ramírez de Arellano E, Jiménez-Orellana M, Viedma E, Sánchez A, Alhambra A, Villa J, Delgado-Iribarren A, Bautista V, Lara N, García-Cobos S, Aracil B, Cercenado E, Pérez-Vázquez M, Oteo-Iglesias J. Revista: Antibiotics (Basel). 2023 Jan 6;12(1):107.

DOI

Evaluation of the Thermal Stability of a Vaccine Prototype Based on Virus-like Particle Formulated HIV-1 Envelope

Aguado-Garcia D, Olvera A, Brander C, Sanchez-Merino V, Yuste E; Vaccines (Basel). 2022 Mar 22;10(4):484

PUBMED DOI

Distribution of Aspergillus Species and Prevalence of Azole Resistance in clinical and environmental Samples from a Spanish Hospital during a three-year study period

Lucio J, Alcazar-Fuoli L, Gil H, Cano-Pascual S, Hernandez-Egido S, Cuetara MS and Mellado E. Mycoses. 2024 Apr;67(4):e13719.

PUBMED DOI

Exploring the sequence diversity and surface expression of Factor H-Binding Protein among invasive serogroup B meningococcal strains from selected European countries

Clark SA, Willerton L, Claus H, Carannante A, Stefanelli P, Abad R, Vázquez JA, Borrow R. Hum Vaccin Immunother. 2024 Dec 31;20(1):2427471

PUBMED DOI

Effects of 3D nanocomposite bioceramic scaffolds on the immune response

4. Cicuendez M., Portolés P., Montes-Casado M., Izquierdo-Barba I., Vallet-Regı M., and Portolés M.T. Effects of 3D nanocomposite bioceramic scaffolds on the immune response. J. Mater. Chem. B, 2014, 2 (22), 3469-3479.

DOI

Botulism in Spain: Epidemiology and Outcomes of Antitoxin Treatment, 1997-2019

Peñuelas M, Guerrero-Vadillo M, Valdezate S, Zamora MJ, Leon-Gomez I, Flores-Cuéllar Á, Carrasco G, Díaz-García O, Varela C. (2022). Botulism in Spain: Epidemiology and Outcomes of Antitoxin Treatment, 1997-2019. Toxins (Basel). 20;15(1):2

PUBMED DOI

Comparison of T24H-his, GST-T24H and GST-Ts8B2 recombinant antigens in western blot, ELISA and multiplex bead-based assay for diagnosis of neurocysticercosis.

Hernández-González A, Noh J, Perteguer MJ, Gárate T, Handali S. Comparison of T24H-his, GST-T24H and GST-Ts8B2 recombinant antigens in western blot, ELISA and multiplex bead-based assay for diagnosis of neurocysticercosis. Parasit Vectors. 2017 May 15;10(1):237.

PUBMED DOI

Seconeolitsine, the novel inhibitor of DNA topoisomerase I, protects against invasive pneumococcal disease caused by fluoroquinolone-resistant strains.

Tirado-Vélez JM, Carreño D, Sevillano D, Alou L, Yuste J, de la Campa AG. Antibiotics 2021; 10:573.

PUBMED DOI

Age-dependent nasal immune responses in non-hospitalized bronchiolitis children

Cortegano I, Rodríguez M, Hernángómez S, Arrabal A, Garcia-Vao C, Rodríguez J, Sandra Fernández S, Díaz J, de la Rosa B, Solís B, Arribas C, Garrido F, Zaballos A, Roa S, López V, Gaspar ML, de Andrés B. Front Immunol 2022 Dec 6:13:1011607.

PUBMED DOI

An increase in erythromycin resistance in methicillin-susceptible Staphylococcus aureus from blood correlates with the use of macrolide/lincosamide/streptogramin antibiotics. EARS-Net Spain (2004-2020).

4. An increase in erythromycin resistance in methicillin-susceptible Staphylococcus aureus from blood correlates with the use of macrolide/lincosamide/streptogramin antibiotics. EARS-Net Spain (2004-2020). Autores: El Mammery A, Ramírez de Arellano E, Cañada-García JE, Cercenado E, Villar-Gómara L, Casquero-García V, García-Cobos S, Lepe JA, Ruiz de Gopegui Bordes E, Calvo-Montes J, Larrosa Escartín N, Cantón R, Pérez-Vázquez M, Aracil B, Oteo-Iglesias J. Revista: Front Microbiol. 2023 Sep 26;14:1220286.

PUBMED DOI

Permanent control of HIV-1 pathogenesis in exceptional elite controllers: a model of spontaneous cure

Casado C, Galvez C, Pernas M, Tarancon-Diez L, Rodriguez C, Sanchez-Merino V, Vera M, Olivares I, De Pablo-Bernal R, Merino-Mansilla A, Del Romero J, Lorenzo-Redondo R, Ruiz-Mateos E, Salgado M, Martinez-Picado J, Lopez-Galindez C; Sci Rep. 2020 Feb 5;10(1):1902

PUBMED DOI

Importance of the Aspergillus fumigatus mismatch repair protein Msh6 in antifungal resistance development

Lucio J, Gonzalez-Jimenez I, Roldan A, Amich J, Alcazar-Fuoli L and Mellado E. J Fungi (Basel). 2024 Mar 12;10(3):210

PUBMED DOI

Resultado falso negativo en diversas PCR multiplex y monoplex en un episodio de bacteriemia por Neisseria meningitidis. Implicaciones diagnósticas, terapéuticas y epidemiológicas [False negative result in both multiplex and monoplex PCR in a case of Neisseria meningitidis bacteremia. Diagnostic, therapeutic and epidemiological implications]

Monforte ML, Cebollada R, Escobar MJ, Abad R, Aspiroz C. Rev Esp Quimioter. 2024 Oct;37(5):427-428

PUBMED DOI

Characteristics of TCR/CD3 complex CD3 chains of regulatory CD4+ T (Treg) lymphocytes: Role in Treg differentiation in vitro and impact on Treg in vivo.

5. Rojo, J. M., G. Ojeda, Y. Y. Acosta, M. Montes-Casado, G. Criado, and P. Portoles. Characteristics of TCR/CD3 complex CD3 chains of regulatory CD4+ T (Treg) lymphocytes: Role in Treg differentiation in vitro and impact on Treg in vivo. J. Leukoc. Biol. 2014, 95 (3): 441-450.

PUBMED DOI

Content with Investigacion Genética Bacteriana .

List of staff

Additional Information

The Pneumococcus Unit is in charge of two very important aspects related to pneumococcus infections, such as epidemiological surveillance and basic and translational research of diseases caused by this pathogen. Our unit contributes to the epidemiological surveillance of invasive pneumococcal disease (IPD), characterizing the serotypes and genotypes of invasive pneumococci circulating in Spain, as well as the evolution of antibiotic resistance in this pathogen. 

Identification of culture-negative samples (CSF and pleural fluids) is performed using real-time PCR. Serotyping is performed using the Dot-blot and PCR-sequencing technique. Genotyping for the study of outbreaks and characterization of clones associated with hypervirulent and/or multiresistant strains is performed using the MLST technique and the analysis of complete genomes by massive sequencing. In addition, antibiotic susceptibility is determined following the EUCAST criteria. 

Our unit belongs to the IBD-labnet network of the ECDC and annually notifies all cases of IPD to the ECDC and also to the IRIS (Invasive Respiratory Infection Surveillance) network. At the level of basic and translational research, our unit is responsible for studying and characterizing different molecular mechanisms of pathogenicity and protection related to pneumococcal infection. Among the main objectives are the molecular characterization of virulence factors, the study of different vaccine candidate proteins and determining the possible impact that tobacco smoke and the formation of biofilms have on the colonization of the respiratory tract.

The Pneumococcus Unit is in charge of two very important aspects related to pneumococcus infections, such as epidemiological surveillance and basic and translational research of diseases caused by this pathogen. Our unit contributes to the epidemiological surveillance of invasive pneumococcal disease (IPD), characterizing the serotypes and genotypes of invasive pneumococci circulating in Spain, as well as the evolution of antibiotic resistance in this pathogen. 

Identification of culture-negative samples (CSF and pleural fluids) is performed using real-time PCR. Serotyping is performed using the Dot-blot and PCR-sequencing technique. Genotyping for the study of outbreaks and characterization of clones associated with hypervirulent and/or multiresistant strains is performed using the MLST technique and the analysis of complete genomes by massive sequencing. In addition, antibiotic susceptibility is determined following the EUCAST criteria. 

Our unit belongs to the IBD-labnet network of the ECDC and annually notifies all cases of IPD to the ECDC and also to the IRIS (Invasive Respiratory Infection Surveillance) network. At the level of basic and translational research, our unit is responsible for studying and characterizing different molecular mechanisms of pathogenicity and protection related to pneumococcal infection. Among the main objectives are the molecular characterization of virulence factors, the study of different vaccine candidate proteins and determining the possible impact that tobacco smoke and the formation of biofilms have on the colonization of the respiratory tract.

Content with Investigacion Genética Bacteriana .