The Type VI secretion system of Rhizobium etli Mim1 has a positive effect in symbiosis. Issue 5 (12th April 2019)

• Record Type: Journal Article
• Authors: Salinero-Lanzarote, Alvaro; Pacheco-Moreno, Alba; Domingo-Serrano, Lucía; Durán, David; Ormeño-Orrillo, Ernesto; Martínez-Romero, Esperanza; Albareda, Marta; Palacios, José Manuel; Rey, Luis
• Is Part Of: FEMS microbiology ecology. Volume 95:Issue 5(2019)
• Publication Date: 2019-04-12
• Subjects: Type VI secretion -- Rhizobium–legume symbiosis -- Rhizobium etli -- effector; Microbial ecology -- Periodicals; Microbiology -- Periodicals; 579.17
• DOI: 10.1093/femsec/fiz054
• Languages: English
• ISSNs: 0168-6496

Abstract

ABSTRACT: The Type VI secretion systems (T6SSs) allow bacteria to translocate effector proteins to other bacteria or to eukaryotic cells. However, little is known about the role of T6SS in endosymbiotic bacteria. In this work we describe the T6SS of Rhizobium etli Mim1, a bacteria able to effectively nodulate common beans. Structural genes and those encoding possible effectors have been identified in a 28-gene DNA region of R. etli Mim1 pRetMIM1f plasmid. Immunodetection of Hcp protein, a conserved key structural component of T6SS systems, indicates that this secretion system is active at high cell densities, in the presence of root exudates, and in bean nodules. Rhizobium etli mutants affected in T6SS structural genes produced plants with lower dry weight and smaller nodules than the wild-type strain, indicating for the first time that the T6SS plays a positive role in Rhizobium –legume symbiosis. Abstract : The T6SS of Rhizobium etli Mim1 plays a positive role in symbiosis with beans and is active at high cell densities and in the presence of plant exudates.