Research Interests

Cell-cell signaling and bacterial communities in plant associated Bacteria. Bacteria, Quorum sensing, Endophytes, LuxR solos, Pseudomonas

Description of Research

The Group focuses on bacterial interspecies signalling in plant-associated microbiomes and the identification and development of plant bacterial probiotics.

The main interest of the laboratory is cell-cell communication in plant-associated bacteria using rice as out model plant. The focus for many years has been on the N-acyl homoserine lactone quorum sensing system of Gram-negative bacteria. Questions that we are addressing on this quorum sensing system are (i) the role of cell-cell signalling in forming and stabilising bacterial plant communities, (ii) how these regulatory systems are regulated in the plant environment and (ii) the role of LuxR solos in cell-cell communication.

We have also developed an interest in how plant microbiomes form and how they are affected upon the arrival of bacterial pathogens. We are using two rice diseases as models; rice sheath brown rot caused by Pseudomonas fuscovaginae and rice foot rot caused by Dickeya zeae. Interests are whether bacterial pathogens significantly affect microbiomes at the infection sites and if interspecies or interkingdom interactions takes place among microbial members of the microbiota.

We are also using the plant microbiome for the isolation and identification of beneficial bacterial endophytes. Endophytes are harmless or beneficial microorganisms that live inside plants. Endophytes which display the trait of plant growth promotion are being studied for their potential use as bioinoculants/biofertilizers. In this aspect we are collaborating with the private sector via our initiative called Strains4Plants.

Recently, we have studied how the microbiome of rice changes upon pathogen attack by Dickeya which causes foot rot, showing cooperation between the pathogen and members of the microbiome (Bez et al, Environ Microbiol, 2021). In addition, we continue to study the role of the LuxR solo regulators in interspecies signalling in the microbiome (Bez et al., mSphere 2021), and have reported a beneficial plant probiotic Pseudomonas strain (Bertani et al., Planta, 2021) and hypothesized on the role of cell-cell interaction in the plant microbiome (Venturi et al, Trends Plant Sci, 2021).

Rice sheath rot in Burundi

Rice with symptoms of sheath rot was studied in Burundi (a) (necrosis, seeds rotten and sterile). b Burundi rice ecology and field sites (lowland and highland) of the outstation of IRRI-Burundi. Red star designates the IRRI field sites in lowland and highland. The symptomatic (diseased) and asymptomatic (healthy) rice sheath plants were sampled in two locations (lowland: Gihanga-Bubanza and highland: Gisha-Ngozi) in two seasons; wet season (April 2017) and dry season (December 2018). The pathobiomes were then determined in order to elucidate the pathogenic agent (Musonerimana et al., 2020).

Recent Publications

Bertani, I., Zampieri, E., Bez, C., Volante, A., Venturi, V., & Monaco, S. (2021). Isolation and Characterization of Pseudomonas chlororaphis Strain ST9; Rhizomicrobiota and in Planta Studies. Plants (Basel, Switzerland)10(7), 1466.

Bez, C., Covaceuzach, S., Bertani, I., Choudhary, K. S., & Venturi, V. (2021). LuxR Solos from Environmental Fluorescent Pseudomonads. mSphere6(2), e01322-20.

Bez, C., Esposito, A., Thuy, H. D., Nguyen Hong, M., Valè, G., Licastro, D., Bertani, I., Piazza, S., & Venturi, V. (2021). The rice foot rot pathogen Dickeya zeae alters the in-field plant microbiome. Environmental microbiology, 10.1111/1462-2920.15726. Advance online publication.

Mosquito, S., Bertani, I., Licastro, D., Compant, S., Myers, M. P., Hinarejos, E., Levy, A., & Venturi, V. (2020). In Planta Colonization and Role of T6SS in Two Rice Kosakonia Endophytes. Molecular plant-microbe interactions : MPMI33(2), 349–363.

Mosquito, S., Meng, X., Devescovi, G., Bertani, I., Geller, A. M., Levy, A., Myers, M. P., Bez, C., Covaceuszach, S., & Venturi, V. (2020). LuxR Solos in the Plant Endophyte Kosakonia sp. Strain KO348. Applied and environmental microbiology86(13), e00622-20.

Venturi, V., & Bez, C. (2021). A call to arms for cell-cell interactions between bacteria in the plant microbiome. Trends in plant science, S1360-1385(21)00180-1. Advance online publication.