The Molecular Microbiology group began its journey on April 11, 1995, led by a board of directors chaired by Josep Casadesús Pursals and with the aim of bringing together the activity of Spanish microbiologists who were using emerging molecular tools at that time. Since then, the work of the chairmen of the boards of directors (Table), whom we thank for their dedication, has been a constant stimulus for the operation of the group.

The group enjoys excellent health and a constant growth in the number of members, which to date exceeds 500. We are also honored to count among our members several of the winners of the Jaime Ferrán award: Enrique Herrero Perpiñán ( 1987), Ernesto García López (1989), Antonio Ventosa Ucero (1991), Íñigo Lasa Uzcudun (2005), Luis Ángel Fernández Herrero (2007), Alejandro Mira Obrador (2009), Bruno González Zorn (2011), David Rodríguez Lázaro ( 2013), Felipe Cava Valenciano (2017), Álvaro San Millán Cruz (2021) and Jerónimo Rodríguez Beltrán (2023). Most of the partners work in Universities (63%) and Public Research Organizations (23%). The rest is divided between hospitals (5%), companies (4%), foreign centers (3%) or foundations (2%). The activity of many of the researchers that make up our group can be consulted in the monographic sections that appeared in the issues of the SEM@foro magazine of December 2014 (number 58) and December 2019 (number 68), the latter coinciding with the 25th anniversary of since the creation of the group.

Our specialized group promotes interaction between microbiologists from different fields with an interest in molecular processes. This objective is fundamentally developed through the holding of biannual meetings (Figure). These meetings, spread throughout Spain, have been held in Pamplona (1996), Valencia (1998), Madrid (2000), Santander (2002), Jaca (2004), Lleida (2006), Cádiz (2008), Barcelona ( 2010), Palma de Mallorca (2012), Segovia (2014), Seville (2016), Zaragoza (2018), Granada (2022) and Santander (2024). From these lines we want to thank the excellent disposition and the work carried out by the organizers of all these meetings, whose philosophy has always been to facilitate the participation of our youngest members, establishing reduced fees for them. In this way, many students have found in these group meetings Micro Molecular a forum where you can publicly present your research and exchange your experiences in a friendly and relaxed atmosphere.

For fourteen years, the group has been announcing an award to distinguish a research work carried out by one of its partners wholly or partially in a Spanish laboratory and whose award takes place within the framework of the biannual meetings, where the winners give the closing conference. . In their first five editions, these awards were sponsored by the Biomedal company and were awarded to the following works:

• Barcelona 2010. Selva L, Viana D, Regev-Yochay G, Trzcinski K, Corpa JM, Lasa I, Novick RP, Penadés JR. (2009). Killing niche competitors by remote-control bacteriophage induction. Proc Natl Acad Sci U S A. 106: 1234-1238.
• Palma de Mallorca 2012. Belda-Ferre P, Alcaraz LD, Cabrera-Rubio R, Romero H, Simón-Soro A, Pignatelli M, Mira A. (2012). The oral metagenome in health and disease . ISME J. 2012 6: 46-56.
• Segovia 2014. Sánchez-Romero MA, Casadesús J (2014). Contribution of phenotypic heterogeneity to adaptive antibiotic resistance. Proc Natl Acad Sci U S A. 111:355-360.
• Sevilla 2016. Cota I, Sánchez-Romero MA, Hernández SB, Pucciarelli MG, García-del Portillo F, Casadesús J. (2015) Epigenetic control of Salmonella enterica O-antigen chain length: a tradeoff between virulence and bacteriophage resistance. PLos Genet 11: e1005667.
• Zaragoza 2018. Castañeda-García A, Prieto AI, Rodríguez-Beltrán J, Alonso N, Cantillon D, Costas C, Pérez-Lago L, Zegeye ED, Herranz M, Plociński P, Tonjum T, García de Viedma D, Paget M, Waddell SJ, Rojas AM, Doherty AJ, Blázquez J. (2017) A non-canonical mismatch repair pathway in prokaryotes. Nature Comm 8: 14246.

Although the exceptional situation generated by the SARS-CoV-2 pandemic prevented us from holding the meeting scheduled for September 2020 in Granada, the following works, awarded in 2020, were presented in an online session held on October 21, 2020:

• • Primer premio: Alejandro González-Delgado A, Rodríguez Mestre M, Martínez-Abarca F, Toro N. (2019) Spacer acquisition from RNA mediated by a natural reverse transcriptase-Cas1 fusion protein associated with a type III-D CRISPR–Cas system in Vibrio vulnificus. Nucleic Acids Res. 47:10202-10211.

• • Second prize: Gonzalo-Asensio J, Pérez I, Aguiló N, Uranga S, Picó A, Lampreave C, Cebollada A, Otal I, Samper S, Martín C. (2018) New insights into the transposition mechanisms of IS6110 and its dynamic distribution between Mycobacterium tuberculosis Complex lineages. PLoS Genet. 14: e1007282.

In 2022, the XIII Meeting of the group was held and the following prizes were awarded for research work:

• Granada 2022.
  • First honorable mention: Catalán-Moreno, A., Cela, M., Menéndez-Gil, P., Irurzun, N., Caballero, C.J., Caldelari, I., Toledo-Arana, A. (2021) RNA thermoswitches modulate Staphylococcus aureus adaptation to ambient temperatures. Nucleic Acids Res. 49:3409-3426.
  • Second honorable mention: Rodríguez-Beltrán, J., Sørum, V., Toll-Riera, M., de la Vega, C., Peña-Miller, R., San Millán, A. (2020) Genetic dominance governs the evolution and spread of mobile genetic elements in bacteria. Proc. Natl. Academic Sci. U.S.A. 117:15755-15762.

In 2024 these awards have been renamed Josep Casadesús Research Awards, in honor of the first president of our group. The awarded works in this edition have been:

• Santander 2024:
  • Hernando-Amado S, Laborda P, Martínez JL (2023). Tackling antibiotic resistance by inducing transient and robust collateral sensitivity. Nature Communications 14:1723.
  • De la Fuente J, Toribio-Celestino L, Santos-Lopez A, León-Sampedro R, Alonso-del Valle A, Costas C, Hernández-García M, Cui L, Rodríguez-Beltrán J, Bikard D, Cantón R, San Millán , A. (2022). Within-patient evolution of plasmid-mediated antimicrobial resistance. Nature Ecology & Evolution 6:1980–1991.

One of the hallmarks that characterizes our meetings is the participation of microbiologists who are at different points in their professional careers, which, together with the almost familiar atmosphere that we like to promote, facilitates the exchange of experiences between our younger and other partners with more extensive experience always willing to put their knowledge at the service of training new generations of microbiologists. We do not want to finish without inviting all the members of the SEM to get to know us and to form part of our specialized group, which is open to all topics in microbiology.