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Mycobacteria

Líneas de investigación

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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.

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Postnatal and adult immunoglobulin repertoires of innate-like CD19(+)CD45R(lo) B Cells.

Prado, C., Rodriguez, M., Cortegano I., Ruiz, C., Alía, M., de Andrés, B., Gaspar, ML. J Inn Inmmunol. (2014) 6: 499-514

PUBMED DOI

Characterization of Carbapenemase-Producing Klebsiella oxytoca in Spain, 2016-2017.

18. Characterization of Carbapenemase-Producing Klebsiella oxytoca in Spain, 2016-2017. Autores: Pérez-Vazquez M, Oteo-Iglesias J, Sola-Campoy PJ, Carrizo-Manzoni H, Bautista V, Lara N, Aracil B, Alhambra A, Martínez-Martínez L, Campos J; Spanish Antibiotic Resistance Surveillance Program Collaborating Group. Revista: Antimicrob Agents Chemother. 2019 May 24;63(6): e02529-18.

PUBMED DOI

HIV-1-specific CD8+ T cell responses and viral evolution in women and infants

Sanchez-Merino V, Nie S, Luzuriaga K*. 2005. J Immunol 175:6976-86.

PUBMED DOI

The global meningitis genome partnership

Rodgers E, Bentley SD, Borrow R, Bratcher HB, Brisse S, Brueggemann AB, Caugant DA, Findlow J, Fox L, Glennie L, Harrison LH, Harrison OB, Heyderman RS, van Rensburg MJ, Jolley KA, Kwambana-Adams B, Ladhani S, LaForce M, Levin M, Lucidarme J, MacAlasdair N, Maclennan J, Maiden MCJ, Maynard-Smith L, Muzzi A, Oster P, Rodrigues CMC, Ronveaux O, Serino L, Smith V, van der Ende A, Vázquez J, Wang X, Yezli S, Stuart JM. J Infect. 2020; 81(4): 510-520

PUBMED DOI

Notch1 regulates progenitor cell proliferation and differentiation during murine yolk sac hematopoiesis

Isabel Cortegano, Pedro Melgar-Rojas, Luis Luna-Zurita, Miguel Ángel Rodríguez-Marcos, MA., Gaspar ML., and José Luis de la Pompa, JL. Cell death and diff. (2014) 21: 1081-1094

PUBMED DOI

Spread of the FAR-MRSA clone, a fusidic acid- and meticillin-resistant Staphylococcus aureus ST121, Europe, 2014 to 2024.

19. Spread of the FAR-MRSA clone, a fusidic acid- and meticillin-resistant Staphylococcus aureus ST121, Europe, 2014 to 2024. Autores: Roer L, Yin N, Denis O, Vendrik KE, Zwittink RD, Notermans DW, Perrin M, Khonyongwa K, Tristan A, Youenou B, Layer-Nicolaou F, Werner G, Enger H, Eikrem ECH, Darenberg J, Mäkitalo B, Paulsson M, Björkman J, Fang H, Hallbäck ET, Sundqvist M, Lindholm L, Moganeradj K, García-Cobos S, Cañada-García JE, Holzknecht BJ, Eriksen HB, Hoppe M, Bartels MD, Samaniego Castruita JA, Urth TR, Larsen AR, Petersen A. Revista: Euro Surveill. 2025 Jul;30(28):2500452.

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Modulation of Env content in virions of simian immunodeficiency virus: correlation with cell surface expression and virion infectivity

Yuste E, Reeves JD, Doms RW, Desrosiers RC*. 2004. J Virol 78:6775-85.

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Epidemiology, molecular characterisation and antimicrobial susceptibility of Neisseria gonorrhoeae isolates in Madrid, Spain, in 2016

María D. Guerrero-Torres, María B. Menéndez, Carmen S. Guerras, Estela Tello, Juan Ballesteros, Petunia Clavo, Teresa Puerta, Mar Vera, Oskar Ayerdi, Juan C. Carrio, Inmaculada Monzo, Jorge del Romero, Julio A. Vázquez, Raquel Abad. 20. María D. Guerrero-Torres, María B. Menéndez, Carmen S. Guerras, Estela Tello, Juan Ballesteros, Petunia Clavo, Teresa Puerta, Mar Vera, Oskar Ayerdi, Juan C. Carrio, Inmaculada Monzo, Jorge del Romero, Julio A. Vázquez, Raquel Abad. Epidemiol Infect. 2019 Sep 24;147:e274

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List of staff

Información adicional

• Taxonomic study. Objective: Association of already described species to new clinical processes. Description of new bacterial species. 

• Sensitivity studies against new antituberculous drugs: Objective: To evaluate the antimicrobial activity of new compounds for human use in clinical strains of Mycobacterium tuberculosis and in other species of non-tuberculous mycobacteria, for subsequent application in the treatment of these infections. 

• Molecular epidemiology of tuberculosis. Objectives: Molecular characterization of the members of the M. tuberculosis complex. Transmission studies with special surveillance of MDR/XDR tuberculosis. 

• Development of new methods of identification and detection of resistance in mycobacteria. Objectives: Optimization and development of molecular techniques for the diagnosis and detection of resistance.

Content with Investigacion Genética Bacteriana .