How Flagella Expression May be Regulated by the Carbon and Energy Source?

Anibal R Lodeiro

doi:10.15226/2376-4589/1/1/00104

Abstract

Bradyrhizobium diazoefficiens has two flagellar systems: a subpolar, constitutive system and a lateral, inducible system. Contrary to other bacterial species, the lateral system is induced in liquid medium in response to the carbon and energy source. Since both flagella are moved by the proton-motive force, a relationship between the energy status of the cell and the signal that triggers lateral flagella expression might exist. Here I discuss how this relationship may control the induction of the lateral flagellar system, and its implicancies for improvement of Bradyrhizobium-based inoculants for soybean plants.

Highlights

Bradyrhizobium is a soil bacterial genus that includes several species of importance due to their use as biofertilizers for soybean crops worldwide
Since the symbiosis only occurs in specialized organs in the roots, seed-inoculated bacteria need moving from the site of inoculation to the sites of infection, and this movement has to occur in the soil, a porous and tortuous medium, which not always contain water enough for bacterial swimming
B. diazoefficiens is the only example known where the lateral flagellar system is induced by the carbon and energy source, and the identity of the signal transducer is a complete enigma

Summary

Introduction

Bradyrhizobium is a soil bacterial genus that includes several species of importance due to their use as biofertilizers for soybean crops worldwide. Since the symbiosis only occurs in specialized organs in the roots, seed-inoculated bacteria need moving from the site of inoculation to the sites of infection, and this movement has to occur in the soil, a porous and tortuous medium, which not always contain water enough for bacterial swimming. B. diazoefficiens USDA 110 possesses two entirely different flagellar systems: a subpolar system and a lateral system [4,5,6].

Results

Conclusion