Pneumococcus
Research Lines
Content with Investigacion .
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 .
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.
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
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 DOIHorizontal 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.
PUBMEDFocusing 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 DOIAntibody 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 DOIRole 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 DOICarbapenemase-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.
DOIDistribution 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 DOIExploring 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 DOIEffects 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.
DOIBotulism 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 DOIComparison 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 DOIAge-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 DOIAn 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 DOIPermanent 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 DOIResultado 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 DOICharacteristics 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 DOIContent with Investigacion .
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Adela González de la Campa
Scientific Investigator
ORCID code: 0000-0002-3598-2548
Dr. Adela González de la Campa obtained her degree in Biology in 1981 and her PhD in 1985 from the Complutense University of Madrid. She did her doctoral thesis in the laboratory of Dr. Miguel Vicente at the Centro de Investigaciones Biológicas of CSIC. Subsequently she worked for 2 years at Brookhaven National Laboratory, Upton, New York, USA in the laboratory of Sandford Lacks. After this postdoctoral stage in the USA, she worked for 3 years as a Reincorporation Fellow at the Centro de Investigaciones Biológicas of CSIC in the laboratory of Dr. Manuel Espinosa. He is a CSIC Senior Scientist since 1990 and Research Scientist since 2007. He participated as group leader of the CIBER of Respiratory Diseases (CIBERES) from 2007 to 2015. Since 1990, she has been the principal investigator of the Bacterial Genetics Unit at the National Centre for Microbiology.
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María José Ferrándiz Avellano
Research Scientist
ORCID code: 0000-0003-1428-9506
Dr. María José Ferrández obtained her degree in Biology in 1990 and her PhD in 1997 from the Complutense University of Madrid. She completed her doctoral thesis at the Centro de Investigaciones Biológicas of CSIC in the laboratory of Dr. Miguel Vicente. She completed her postdoctoral training at the Centro Nacional de Microbiología of Instituto de Salud Carlos III (1998-2001 and 2003-2006) and at the Institute of Infection and Immunity (University of Nottingham) from 2001- 2003. From 2007 to 2015, she participated as a researcher of the CIBER of Respiratory Diseases (CIBERES). Since 2006, she is a Full Scientist at the National Microbiology Center of the ISCIII.
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Mónica Amblar Esteban
Research Scientist
ORCID code: 0000-0003-3530-615X
Dr. Mónica Amblar obtained her degree in Biology in 1993 and her PhD in 2000 from the Complutense University of Madrid. She did her doctoral thesis in the laboratory of Dr. Paloma López at the Centro de Investigaciones Biológicas of CSIC. Subsequently, she worked for 5 and half years at the Instituto de Tecnología Química e Biológica/Universidade Nova de Lisboa, Oeiras (Portugal) in the laboratory of Prof. Cecilia M. Arraiano. After this postdoctoral stage he rejoined the Centro de Investigaciones Biológicas del CSIC where he worked for 2 years as a Postdoctoral Researcher in the laboratory of Dr. Paloma López. Subsequently, he joined the National Microbiology Center of the ISCIII with a Ramón y Cajal contract and in 2010 he obtained a position as a Full Scientist at the same center.
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Pablo Herrera Marcelino
Research Assistant
ORCID code: 0009-0003-5137-3712
Graduated in Biochemistry in 2022 from the University of Malaga, and in Master's degrees in Microbiology and Parasitology (2024) and Virology (2025) from the Complutense University of Madrid. He also holds degrees in Clinical Laboratory Science (2023) from the same university and in Biotechnology Applied to Health (2023) from the UNED. He currently has a research assistant contract focusing on the study of pneumococcal proteins involved in RNA interaction.
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Laura Alfonso Alarcón
PhD student
ORCID code: 0000-0003-1560-1100
Degree in Biochemistry in 2020 from National University of Asunción (Paraguay). Master in Microbiology and Health in 2024 from Pais Vasco University (Spain). Stays in Paraguay in Instituto de Investigaciones en Ciencias de la Salud; Facultad de Ciencias Químicas and Hospital Nacional de Itaugua. She is actually a predoctoral student of the Microbiología y Parasitología program of Complutense University of Madrid, with a “Don Carlos Antonio López” (BECAL) fellowship from Paraguay Goverment.
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.