Bacterial Genetics
Research Lines
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Research
The Molecular Virology group focuses its research on the study of HIV-1 genetic variation and viral evolution using both in vitro and ex vivo approaches, structured around the following research lines:
- Non-progressor patients. These patients maintain control of the disease in the absence of antiretroviral therapy and have therefore been proposed as a model of functional cure. Our objective is to study the contribution of viral factors to disease control through biological characterization and analysis of viral evolution in individuals with undetectable viral loads (elite controllers, EC), compared with individuals showing other patterns of viral control.
- Viral envelope. This viral protein is key in determining viral fitness. Therefore, its functionality significantly affects infection progression. In collaboration with Dr. Blanco and Dr. Valenzuela, we study which specific events (CD4 binding, fusogenicity, etc.) are associated with envelope functionality. To this end, we have analyzed envelopes from individuals with different patterns of disease progression. Some of these have been contributed to the AIDS Research Network envelope biobank for broader use.
- Dual infection. Infection with more than one viral variant (either through co-infection or superinfection) may have consequences for infection pathogenesis. Within our group, different aspects of DI have been analyzed, including its detection in non-progressor patients, its prevalence and incidence in Spain, and its influence on the neutralizing antibody response.
- Molecular Epidemiology. The group has analyzed viral evolution throughout the epidemic in Spain and in other countries (the Netherlands, Italy, Germany, Uruguay, Panama, Brazil, etc.).
- Role of amino acid residues in reverse transcriptase. We study the role of specific amino acid residues in HIV-1 reverse transcriptase in enzymatic function and replication capacity using an infectious molecular clone previously obtained by the group.
- “In vitro” variability. Serial passage studies have been used to detect the mechanisms responsible for the gain or loss of viral fitness.
- Antiviral studies. We have analyzed the selection of resistance mutations in vitro against different antivirals, as well as the effect of these mutations on viral fitness, and the activity of new antivirals such as ATR inhibitors.
Virological Diagnosis and Reference in HIV and HTLV Infections
The research group provides diagnostic and reference activities through the service portfolio of the National Center for Microbiology to the entire Spanish National Health System.
These services include:
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Diagnosis and reference of HIV infection (types 1 and 2) through detection of specific antibodies and detection of proviral DNA by PCR.
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Diagnosis and reference of HTLV-I/II infection through detection of specific antibodies and detection of proviral DNA by PCR. Quantification of HTLV-1 proviral load by real-time PCR.
European Union Reference Laboratory (EURL) in the field of in vitro diagnostic medical devices for microbiological diagnosis (IVD) of HIV and HTLV (Regulation 2023/2713 of December 5th, 2023). Our role is to confirm the reliability and effectiveness of devices for detecting these pathogens and to ensure their specific performance requirements through laboratory testing before they can be marketed within the European Union.
Research projects
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- Towards a functional cure: Implications of early antiretroviral therapy and hormonal changes on the HIV reservoir in perinatally infected adolescents. Health Research Fund (FIS) – Carlos III Health Institute (01/01/2026 – 31/12/2028). €72,000. PI: María Pernas, Concepción Casado.
- Determination of factors associated with protection against Human Immunodeficiency Virus type 1 reinfection: Identification of correlates of protection. 9th Gilead Fellowship Program for Biomedical Research, Gilead Sciences, S.L. (01/07/2023 – 30/06/2025). €16,330. PI: María Pernas.
- Impact of the envelope on HIV viral replication: New avenues for vaccine development. Health Research Fund (FIS) – Carlos III Health Institute (01/01/2020 – 31/12/2023). €53,000. PI: María Pernas, Concepción Casado.
- Study of HIV-1 virulence in recently infected patients and its contribution, together with clinical and epidemiological factors, to disease progression. Ministry of Economy and Competitiveness. State Program for Scientific and Technical Research and Innovation (30/12/2016 – 30/06/2021). €145,000. PI: Concepción Casado, Cecilio López-Galíndez.
-Contribution of HIV-1 dual infection to virological and clinical evolution in homo/bisexual men. Health Research Fund (FIS) – Carlos III Health Institute (01/01/2014 – 31/01/2016). €74,410. PI: Cecilio López-Galíndez.
- Characterization of non-pathogenic HIV variants obtained “ex vivo” and “in vitro” for the study of disease pathogenesis. Ministry of Science and Innovation (01/01/2011 – 31/01/2014). €169,400. PI: Cecilio López-Galíndez.
- Spanish AIDS Research Network (RIS-RETIC). Carlos III Health Institute (02/01/2017 – 02/01/2022). €195,212. PI: Cecilio López-Galíndez, Concepción Casado.
Publications
High-Quality Draft Genome of Babesia divergens, the Etiological Agent of Cattle and Human Babesiosis.
8. Cuesta I; González LM; Estrada K; Grande R; Zaballos A; Lobo CA; Barrera J; Sanchez-Flores A; Montero E. 2014. High-Quality Draft Genome of Babesia divergens, the Etiological Agent of Cattle and Human Babesiosis. Genome Announcement. 2: e01194-14.
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.
PUBMEDEmergence of linezolid-resistant coagulase-negative staphylococci in an intensive care unit.
Emergence of linezolid-resistant coagulase-negative staphylococci in an intensive care unit. Balandin B, Lobo B, Orden B, Román F, García E, Martínez R, Valdivia M, Ortega A, Fernández I, Galdos P. Infect Dis (Lond). 2016;48(5):343-9.
PUBMEDContent with Investigacion .
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Almudena Cascajero Díaz
Técnico de laboratorio
ORCID code: 0000-0002-9654-3100
Técnico Superior de Actividades Técnicas y Profesionales (Unidades de Inmunopatología del SIDA y Legionella, Centro Nacional de Microbiología). Clinical Diagnostic Laboratory Technician by IES Renacimiento de Madrid.
Experience in cloning techniques and characterization of neutralizing antibodies and participation in different projects on the pathogenesis of HIV by studying the viral envelope and the mechanisms of resistance to antiretroviral drugs. This experience has subsequently allowed me to participate in 5 multicenter clinical studies studying the immune response against different variants of SARS-CoV-2.
Since 2021, I also participate as a laboratory technician in the Legionella Unit as a support to the Spanish National Health System through the microbiological surveillance of the disease to contribute to the prevention and control of legionellosis.
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Laura del Estal Gómez
Ayudante de investigación
ORCID code: 0009-0000-2773-8986
Graduada en Biología Sanitaria por la Universidad de Alcalá. Máster Universitario en Microbiología Aplicada a la Salud Pública e Investigación en Enfermedades Infecciosas.
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Caroline Stephanie Crisóstomo Vergara
Técnico de Laboratorio
ORCID code: 0009-0008-0525-1737
Técnico de Laboratorio. Técnico superior de Laboratorio Clínico y Biomédico por la Escuela Técnica de Enseñanzas Especializadas de Madrid. Máster en Microbiología Clínica por el Instituto Europeo de Química, Física y Biología de Madrid.
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Fernando González Camacho
Científico Titular
ORCID code: 0000-0003-3175-9004
Licenciado en Ciencias Biológicas por la Universidad de Salamanca y Doctor por la Universidad Autónoma de Madrid. Actualmente, es Científico Titular de plantilla en el Centro Nacional de Microbiología (CNM) del Instituto de Salud Carlos III (ISCIII). Responsable de la Unidad de Legionella del Laboratorio de Referencia e Investigación en Enfermedades Bacterianas transmitidas por agua y alimentos.
A nivel europeo es sustituto (Alternate) al National Focal Point para la enfermedad del legionario en el ECDC y es OCP (Operational Contact Point) en microbiología para la legionelosis en la European Legionnaires' Disease Surveillance Network (ELDSNet).
Coordina las líneas de investigación del laboratorio que se desarrollan en tres perspectivas diferentes: en las instalaciones colonizadas, estudios sobre la resistencia a los tratamientos y su persistencia; en la clínica, sobre factores de virulencia y su interacción con el sistema inmune; y en la vigilancia microbiológica, sobre la mejorar de los métodos de caracterización del microorganismo.
Es Investigador Principal en el proyecto “Búsqueda de biomarcadores de patogenicidad en Legionella spp con interés predictivo de riesgo de infección".
Es miembro de distintas sociedades científicas como son la Sociedad Española de Salud Ambiental (SESA), Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC) y la European Society of Clinical Microbiology and Infectious Diseases (ESCMID).
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Juana María González Rubio
Científica Titular
ORCID code: 0000-0001-6979-2964
La Dra. Juana María González Rubio es Licenciada en Bioquímica por la Universidad de Salamanca y Doctora por la Facultad de Medicina de la Universidad Autónoma de Madrid. Actualmente, es Científico Titular de plantilla en el Centro Nacional de Microbiología del Instituto de Salud Carlos III (ISCIII), donde trabaja en la Unidad de Legionella del Laboratorio de Referencia e Investigación en Enfermedades Bacterianas transmitidas por agua y alimentos.
Dentro del laboratorio, realiza las actividades propias del Programa de Vigilancia Microbiológica de Legionella, y lleva las líneas de investigación del laboratorio sobre la caracterización de biofilms y la puesta a punto de nuevas técnicas para la caracterización de Legionella. También forma parte del equipo investigador del proyecto “Búsqueda de marcadores de patogenicidad para el análisis de riesgos en las instalaciones".
Anteriormente, ha trabajado en la Unidad de Biomonitorización humana del Centro Nacional de Sanidad Ambiental (ISCIII) participando en diferentes proyectos de investigación relacionados con la Sanidad Ambiental, siendo el último más destacado el proyecto “HBM4EU" en el que ha trabajado hasta junio de 2023.
List of staff
Additional Information
Streptococcus pneumoniae is a human pathogen that, despite the development of vaccines, continues to be an important cause of mortality and morbidity. We investigate the mechanisms of antibiotic resistance in this bacterium. On the one hand by identifying new therapeutic targets and on the other hand by investigating the molecular basis of the action of antibiotics already used in clinical practice (the fluoroquinolones levofloxacin and moxifloxacin) or not yet used (seconeolitsine). For this purpose, we used a multidisciplinary analysis involving genomics, transcriptomics and proteomics to understand the organization of the S. pneumoniae chromosome and the identification of the factors that stabilize this organization, including ncRNAs. Changes in the level of global supercoiling, either by inhibition of gyrase (decrease) or by inhibition of topoisomerase I (increase) alter the transcriptome. The modulated genes are located in domains, whose genes show specific functional characteristics. The aim is to identify new factors essential for S. pneumoniae physiology and to characterize transcriptional regulation in response to topological stress. In addition, RNA interference technology and CRISPR systems will be used as novel antibacterials. These studies will establish the bases for translational research aimed at the development of new therapeutic targets for the treatment of pneumococcal diseases.
Streptococcus pneumoniae is a human pathogen that, despite the development of vaccines, continues to be an important cause of mortality and morbidity. We investigate the mechanisms of antibiotic resistance in this bacterium. On the one hand by identifying new therapeutic targets and on the other hand by investigating the molecular basis of the action of antibiotics already used in clinical practice (the fluoroquinolones levofloxacin and moxifloxacin) or not yet used (seconeolitsine). For this purpose, we used a multidisciplinary analysis involving genomics, transcriptomics and proteomics to understand the organization of the S. pneumoniae chromosome and the identification of the factors that stabilize this organization, including ncRNAs. Changes in the level of global supercoiling, either by inhibition of gyrase (decrease) or by inhibition of topoisomerase I (increase) alter the transcriptome. The modulated genes are located in domains, whose genes show specific functional characteristics. The aim is to identify new factors essential for S. pneumoniae physiology and to characterize transcriptional regulation in response to topological stress. In addition, RNA interference technology and CRISPR systems will be used as novel antibacterials. These studies will establish the bases for translational research aimed at the development of new therapeutic targets for the treatment of pneumococcal diseases.