2nd workshop in microbial molecular biology

The “2nd Workshop in Microbial Molecular Biology” was the second edition of a scientific meeting organized by the molecular microbiology community of São Paulo State (Brazil) and was held over 3 days (5–7 December), at the University of Campinas (UNICAMP), Campinas, Brazil. The first edition, held in 2017 at the Institute of Biomedical Sciences of the University of São Paulo (ICB/USP), was conceived as a dedicated new forum to bring together the growing community of researchers working on molecular microbiology in the state of São Paulo, fostering new collaborations and also creating opportunities for early career scientists and students to present their work and discuss science with international guests. The 2nd Workshop marked the return to in-person activities after the COVID pandemic and covered the most recent topics in Molecular Microbiology, such as antimicrobial resistance mechanisms, host-pathogen interaction, genetics and cellular biology of microorganisms and phages. To motivate the participation of the community, no registration fees were charged, which was possible due to the financial support obtained from Fundação de Amparo à Pesquisa do Estado de São Paulo, the Vice-Rectorate of Research of UNICAMP and the Graduate School of Genetics and Molecular Biology (IB-UNICAMP). The workshop included lectures from seven international speakers from three different countries and five symposia, presented by researchers from the States of São Paulo and Paraná. It also included a poster session with 60 participants and three oral presentations from students and early career scientists, which were selected from submitted abstracts. Prizes were awarded for the selected oral presentations and for the three best poster presentations, thanks to a sponsorship from the Molecular Microbiology Journal. The meeting started with a lecture from Davide Roncarati from the University of Bologna (Italy), who discussed important aspects of Helicobacter pylori pathogenesis and its gene regulation, focusing on the role of the orphan response regulator HP1043, and the metal-dependent transcriptional repressors Fur and NikR (Vannini et al., 2022). HP1043 is an essential protein that regulates fundamental cellular processes and perspectives for its use as a target for new antimicrobial drugs were discussed by Davide (Antoniciello et al., 2022; Pelliciari et al., 2017; Zannoni et al., 2021). Next was Albert Guskov, from the University of Groningen (Netherlands), presenting data on structural characteristics of Candida albicans 80S ribosomal subunit complexed with inhibitors, as part of a strategy for the development of new antifungal drugs. Albert also showed recent results on the structural characterization of vitamin B transporters from Mycobacterium tuberculosis (Rempel et al., 2020). The discussion on mechanisms of antimicrobial resistance and drug development continued in a Symposium chaired by Marilis Marques (ICB/USP). First, Rebeka Fanti (Center of Medicinal Chemistry/UNICAMP) presented recently published results describing the development of a new bioluminescence-based assay to evaluate the binding of chemical compounds to a known target in living bacterial cells (Fanti et al., 2022). Rebeka showed how she used the Bioluminescence Resonance Energy Transfer Assay (BRET assay) to identify new compounds able to bind dihydrofolate reductase in Escherichia coli and Mycobacterium abscessus. Next, Márcio Dias (ICB/USP) showed structural and biophysical data that dissected the molecular mechanisms of resistance to the drug isoniazid due to mutations in its target, the enzyme InhA. The mutations were identified in seven Mycobacterium tuberculosis clinical isolates. Regina Baldini (Chemistry Institute/USP) closed the first morning session, discussing new findings from her research group about the cold shock response of Pseudomonas aeruginosa. The afternoon session was opened with a brilliant lecture from Mario Feldman (Washington University in Saint Louis, USA), discussing work from his laboratory to dissect the mechanisms used by Acinetobacter baumannii to cause urinary tract infections. In the afternoon symposium about macromolecular machines, chaired by Andrea Balan, we have had exciting talks by Chuck Farah (Chemistry Institute/USP) and Ethel Bayer-Santos (ICB/ USP), who unveiled recent findings from their work on bactericidal secretion machines. Dr. Farah discussed mechanisms of secretion by a type IV secretion system (T4SS) from the phytopathogenic bacterium Xanthomonas citri and Dr. Bayer-Santos presented new data on studies of secreted effectors of type VI secretion systems (T6SS) from Salmonella. The symposium was closed by a talk selected from submitted abstracts by the scientific advisory committee. The student Enzo Sichi de Mello presented results obtained during his ongoing undergraduate internship at Cristina Alvarez-Martinez laboratory (Institute of Biology, UNICAMP) about the signaling pathway that induces an anti-amoeba T6SS of X. citri. After an exciting first day of great science, the social hour was special, with a big gathering to watch a thrilling game of the Brazil soccer squad in the World Cup. The second day of the meeting started with Paul Straight (Texas A&M University, USA) presenting beautiful data describing how bioactive metabolites modulate bacterial competition and how understanding the competitive interactions can lead to discovery of new bioactive metabolites. Next, Thierry Soldati (University of Geneva, Switzerland) kick-started the discussion on host-pathogen interaction, presenting work from his laboratory using the Dictyostelium model system to understand the intricate interactions between mycobacteria and phagocytic cells. In particular, he showed evidence that a TRAF-like E3 ubiquitin ligase, TrafE, coordinates endolysosomal damage response and cell-autonomous immunity to Mycobacterium marinum. Thierry could not come to Brazil this time, so we took advantage of an online streaming platform for his presentation and interaction with the audience. In the morning symposium chaired by Andrea Balan (ICB/USP), four speakers presented fantastic talks on distinct aspects of bacteria – host interactions. Dario Zamboni (Ribeirão Preto Medical School/USP) showed data from studies using Legionella pneumophila as a model to study the innate immunity response and how immune receptors are activated to promote pathogen clearance. Reinaldo Neto (from the Alessandra Alves Souza group at Agronomic Institute – IAC) shifted gears to unveil a plant gene that confers susceptibility to infection by X. citri, which causes citrus canker disease. Reinaldo also discussed a new strategy to generate plants resistant to the disease. Next, Marco Vinolo (Institute of Biology/UNICAMP) showed us how metabolites from the host microbiota modulate the immune response to bacterial and virus pathogens. Luís Soares Neto (Biosciences Institute/USP) closed the morning symposium describing structural data on a class of antioxidant enzymes from bacterial pathogens, the Ohr family (Organic Hydroperoxide Resistance proteins), which are found in bacteria and fungi. Luis also discussed their potential use as targets for antimicrobial drug development. The afternoon started with a thought-provoking lecture from Jonathan Dworkin (Columbia University, USA), whose participation was possible with the help of live streaming. The audience was delighted with the elegant experiments from his laboratory demonstrating the mechanisms that control ribosome arrest in quiescent bacteria and its reactivation by transcription upon nutrient availability (Feaga & Dworkin, 2021). In the afternoon symposium chaired by Frederico Gueiros Filho, (IQ/USP), five speakers discussed distinct aspects of bacterial genetics and physiology. First, José Freire da Silva Neto (Ribeirão Preto Medical School/USP) talked about strategies employed by Chromobacterium violaceum to cope with metal limitation and their importance for host colonization (de Lima et al., 2022). Then, Marilis Marques (ICB/USP) showed recent data from her laboratory on the cold shock response of Caulobacter crescentus and the role of an RNA helicase from the DEAD-box family in mRNA stability. Next, Rodrigo Galhardo (ICB/USP) presented interesting new data on the distribution of Integrative and Conjugative Elements (ICEs) in clinical isolates of Proteus mirabilis. The symposium was closed by a talk from Edileusa Gerhardt, from the Federal University of Paraná, demonstrating new roles for PII family of proteins in distinct metabolic pathways of the nitrogen-fixing bacterium Azospirillum brasilense. To wrap-up the day, PIs, students and international guests mingled in a lively poster session, with 60 posters presented by students and early career researchers. A scientific advisory board was assembled to help in the very hard task of selecting the three best posters among so many excellent presentations. The last day of the meeting started with a lecture from Simon Dove, from Boston Children's Hospital, Harvard Medical School (USA). Simon presented his work on a self-lysis pathway induced in a subset of cells of Pseudomonas aeruginosa upon DNA damage, which contributes to bacterial virulence (Peña et al., 2021). He showed how DNA damage triggers a unique regulatory cascade involving a transcriptional regulator (AlpA) acting as an antiterminator to induce expression of virulence genes in P. aeruginosa. Next, were two oral presentations from submitted abstracts. Julia Takuno Hespanhol, a Master's student from Ethel Bayer-Santos laboratory (ICB/USP) presented their recent work describing antibacterial toxins secreted by a T6SS from Salmonella bongori that function as endonucleases, generating double-strand breaks in the DNA of target cells (Hespanhol et al., 2022). Letícia Franco, a post-doc from Mario Henrique Barros group (ICB/USP) discussed work performed with Alexander Tzagoloff (Columbia University, USA) describing the mechanisms of assembly of cytochrome oxidase and ATP synthase in Saccharomyces cerevisiae. Our final symposium chaired by Rodrigo Galhardo followed their presentations, with three talks discussing distinct pathways for transport of proteins and small molecules in bacteria and yeast. Andrea Balan (ICB/USP) showed a model based on structural data on how activity of an ABC transporter from Mycobacterium tuberculosis may be controlled by phosphorylation on its FHA domains (Cabarca et al., 2021). Next, Cristiane Guzzo (ICB/USP) talked about the characterization of outer membrane vesicles from X. citri, which was followed by Fausto Almeida (Ribeirão Preto Medical School/USP), showing work done by his research group on the role of fungal extracellular vesicles in immunomodulation and inter-species cellular communication. Before the closing remarks, the excitement was big for the announcement of the three winners of the Molecular Microbiology Journal prizes for best poster presentations: the PhD candidates Gabriel Guarany (Cristiane Guzzo's lab) and Bianca Bomtempi (José Freire's lab) and the Masters student Thiago Rodrigues (Chuck Farah's lab). We were very excited to promote an in-person scientific event, after a long period of virtual meetings and social distancing due to COVID-19 pandemic. The 2nd Workshop in Microbial Molecular Biology was an excellent occasion to stimulate students to discuss their research with a diverse and highly specialized audience and promote the emergence of new collaborative projects. The participation of seven international speakers illustrates the international characteristic of the event, which may lead to new partnerships with institutions and researchers from abroad. This certainly impacted positively in the success of the event. We would like to thank all colleagues from the many research institutions of the São Paulo State who actively engaged in the event, the support from the Institute of Biology (UNICAMP) and all the students from our laboratories, for the valuable collaboration with the organization of the workshop. We hope that the event becomes a tradition in our Brazilian scientific community in years to come. FAPESP grant number 2022/09730-0, FAEPEX Grant Number 2721/22 and Code 001. Data sharing is not applicable to this article as no new data were created or analyzed in this study.