I obtained a Bachelor’s degree in biomedicine (1996) at the Universidade Federal do Estado do Rio de Janeiro, a Master (1998) and a Ph.D. (2003) at the Universidade Federal do Rio de Janeiro (UFRJ). I completed my post-doctoral work at the Fiocruz, Brazil (2003-2004), and at the Université Libre de Bruxelles (2012-2014), in Belgium. I have been a full professor at the UFRJ since 2004. I received a grant for Scientists of Rio de Janeiro State (from 2009 to date), and CNPq Research Scientist fellowship (from 2016 to date). I have been elected to the Board of the International Marine Biotechnology Association (IMBA-EUA, 2022-2031). I currently develop and coordinate research activities in the Marine and Molecular Bacteriology Laboratory at the Institute of Microbiology, UFRJ, where I supervise undergraduate and graduate students. My research focuses on microbial diversity in natural and human-impacted aquatic ecosystems (freshwaters, coastal waters, marine caves, sediments); symbioses of
EDUCATION
I obtained a Bachelor’s degree in biomedicine (1996) at the Universidade Federal do Estado do Rio de Janeiro, a Master (1998) and a Ph.D. (2003) at the Universidade Federal do Rio de Janeiro (UFRJ). I completed my post-doctoral work at the Fiocruz, Brazil (2003-2004), and at the Université Libre de Bruxelles (2012-2014), in Belgium. I have been a full professor at the UFRJ since 2004.
RESEARCH, TEACHING, or OTHER INTERESTS
Applied Microbiology and Biotechnology, Microbiology
Microbial bioemulsifiers as tools in biofilm disruption and prevention: state-of-the-art and emerging frontiers G. R. Dias, Erica de Souza Monteiro, B. F. R. de Oliveira, Marinella Silva Laport Critical Reviews in Microbiology, 2026 Although biofilms pose significant challenges in healthcare and in different industries, main antibiofilm agents currently used for surface disinfection and clinical applications often exhibit harmful side effects and contribute to the development of antimicrobial resistance. To tackle this challenge many biomolecules have been studied as alternatives, including bioemulsifiers, amphiphilic polymers that exhibit low toxicity and high biodegradability yet remain largely unexplored to date. By covering publications from 1983 to early 2025, this review aims to compile the current knowledge on bioemulsifiers from different microbial sources with a focus on their relevant properties as promising antibiofilm agents. Research on probiotics, often involving producer strains isolated from dairy products and animal microbiomes, focusing on marine-derived microorganisms were the most prominent fields benefiting from these molecules. Among different molecules, polysaccharides stood out, especially those from cultivable bacteria. This review focuses on key physico-chemical properties, such as their ability to alter surface hydrophobicity and to inhibit quorum sensing, while providing a comprehensive overview of their putative antibiofilm mechanisms. Finally, we highlight several identified bottlenecks and discuss key strategies and recent advances in metabolic and molecular engineering to instigate the research appetite on unlocking the full potential of microbial bioemulsifiers for biofilm control and prevention.
Gems From the Caves: Genomic Insights Into the Biosynthetic Potential of Antimicrobial-Producing Bacteria Associated With Tropical Cave-Dwelling Sponges Gabriel Rodrigues Dias, Bruno Francesco Rodrigues de Oliveira, Joana Sandes, Guilherme Muricy, Marinella Silva Laport Environmental Microbiology, 2026 Submarine caves are promising frontiers for novel biomolecules active against multidrug‐resistant bacteria. These habitats harbour rich communities of marine sponges, whose microbiomes produce diverse bioactive metabolites. The present study investigates the potential of bacteria isolated from cave‐dwelling marine sponges of the class Demospongiae of a tropical archipelago for the production of antimicrobial substances and reveals their biosynthetic diversity by genomic analyses. Ten out of the 89 antimicrobial‐producing strains showed inhibitory activity against Gram‐positive and Gram‐negative bacteria, encompassing strains with multidrug‐resistant phenotypes. Biosynthetic gene clusters (BGCs) encoding antimicrobial‐active metabolites were predicted in these sponge‐derived pseudomonads. Most BGCs exhibited low similarity (< 80%) with known clusters, indicating potential for novel metabolite discovery. Comparative genomics across Pseudomonadaceae genomes revealed both species‐specific and shared BGCs, including conserved clusters encoding for koreenceine and bokeelamides biosynthesis. Some cryptic BGCs encoded antimicrobial peptides (AMPs) together with proteins associated with maturation, regulation, immunity and export, suggesting roles in observed bioactivity. Altogether, this work expands the genomic and biosynthetic landscape of sponge‐associated Pseudomonadaceae and uncovers promising gene clusters for the biotechnological exploration of novel antimicrobials.
Unveiling the genomic and phenotypic landscape of Acinetobacter species from different environmental sources in Brazil Amanda Yaeko Yamada, Anna Luiza Bauer Canellas, Matheus Nunes Diniz, Pedro Smith Pereira Ferraro, Daniel de Sena Miranda, Ana Beatriz Nascimento Costa, Marlon Benedito Nascimento Santos, Karoline Rodrigues Campos, Claudio Tavares Sacchi, Beatriz Balthazar Abdon, Gabrielle da Silva Oliveira Alves, Matheus de Oliveira Nithack Marques, Guilherme Muricy, Marinella Silva Laport, Carlos Henrique Camargo Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology, 2026
Assessment of Antimicrobial Resistance and Virulence of Biofilm-Forming Uropathogenic Escherichia coli from Rio de Janeiro Maria Clara F. Oliveira, Anna Luiza B. Canellas, Lidiane C. Berbert, Alexander M. Cardoso, Vitoria A. Silva, Samantha S. T. Garutti, Débora Hosana F. Rangel, Rubens Clayton S. Dias, Jamila Alessandra Perini, Claudia R. V. M. Souza, Thiago P. G. Chagas, Marinella S. Laport, Flávia Lúcia P. C. Pellegrino Antibiotics, 2025 Background/Objectives: Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections in both community and hospital settings worldwide. Antimicrobial-resistant UPEC strains pose a significant challenge for effective antibiotic therapy. In this study, 50 bacterial isolates recovered from urine samples of patients attended in different sectors of a public hospital in Rio de Janeiro over five months were analyzed to assess antimicrobial resistance and virulence profiles through broad gene screening. Methods: Biofilm production was assessed using a semi-quantitative adherence assay. PCR was employed to investigate 27 resistance genes, 6 virulence genes, sequence types (STs), and phylogroups. Susceptibility to 25 antimicrobial agents was determined by disk diffusion testing. Furthermore, the pathogenic potential was evaluated in vivo using the Tenebrio molitor larvae infection model. Results: Most UPEC isolates were moderate or strong biofilm producers (41/50; 82%). The sul1 and sul2 resistance genes were the most frequently detected (58%). Two virulence gene patterns were identified: fyuA, iutA, fimH, cnf1 and fyuA, iutA, fimH (13 isolates; 26%). ST131 and ST73 were the most common sequence types (16% each), and phylogroup B2 was the most prevalent (50%). Thirty isolates (60%) were multidrug-resistant, most of which belonged to phylogroup B2. UPEC exhibited dose-dependent lethality, causing 100% mortality at 2.6 × 108 CFU/mL within 24 h. Conclusions: These findings reinforce the urgent need for surveillance strategies and effective antimicrobial stewardship in clinical practice.
From farm effluent to biotechnological potential: pGLS, a novel and resilient temperate bacteriophage with synergistic activity and broad antibiofilm properties against Staphylococcus and Mammaliicoccus Vitor Emanuel Lanes Viana, Faizan Ahmad, Samuel Sathler Martuchelle, Sandy de Almada Estanislau, Nohman Rasheed, Marinella Silva Laport, Monalessa Fábia Pereira, Marcia Giambiagi-deMarval, Ciro César Rossi Journal of Applied Microbiology, 2025 Aims This study aimed to isolate and characterize a bacteriophage from dairy farm effluents capable of targeting Mammaliicoccus sciuri, a multidrug-resistant opportunistic pathogen. The biotechnological potential of the phage, including its antibiofilm activity, synergistic interactions with antibiotics, and genomic features, was also assessed. Methods and results The bacteriophage pGLS was isolated using M. sciuri GLS3 as the host strain, exhibiting extreme specificity by lysing only its host. Despite its narrow lytic spectrum, pGLS effectively disrupted biofilms formed by multiple Staphylococcaceae species, including multidrug-resistant strains, and demonstrated synergism with erythromycin, significantly reducing the minimum inhibitory concentration of both the phage and the antibiotic. The phage also displayed remarkable stability under extreme environmental conditions, such as UV exposure and a wide range of pH and temperature. Genomic analysis classified pGLS as a novel temperate phage with a 41 499 bp genome encoding 67 open reading frames, 52% of which were functionally annotated. No virulence or antimicrobial resistance genes were detected, reinforcing its safety for therapeutic applications. Conclusion The unique genomic characteristics, high environmental resilience, and antibiofilm efficacy of pGLS highlight its strong biotechnological potential for mitigating antimicrobial resistance, particularly in livestock settings. Its synergistic interactions with antibiotics further support its potential as an adjunct therapy against resistant Staphylococcaceae infections.
Bioemulsifier from sponge-associated bacteria reduces staphylococcal biofilm Gabriel Rodrigues Dias, Jéssyca Freitas-Silva, Marianna Machado de Carvalho, Victor Feliciano dos Santos Ramos, Guilherme Muricy, Juliany Cola Fernandes Rodrigues, Brunno Renato Farias Verçoza Costa, Bruno Francesco Rodrigues de Oliveira, Marinella Silva Laport Microbial Pathogenesis, 2024
Characterization of Cultivable Bacteria from Brazilian Sponges Juliana F. Santos-Gandelman, Olinda C. S. Santos, Paula V. M. Pontes, Cleyton Lage Andrade, Elisa Korenblum, Guilherme Muricy, Marcia Giambiagi-deMarval, Marinella S. Laport Marine Biotechnology, 2013