Luz E de-Bashan
The Bashan Institute of Science, USA
Title: Creation of synthetic mutualism to improve understanding of the relationships between microalgae and bacteria in fresh water
Biography
Biography: Luz E de-Bashan
Abstract
A simple, quantitative synthetic mutualism model, off ering a convenient and basic approach to studies of plant-bacterium interactions was developed and tested. Th is model involves immobilizing a unicellular, freshwater microalga, a species of Chlorella that serves as the plant and a plant growth-promoting bacterium (PGPB), a strain of a species of Azospirillum of agricultural origin. Th e two micro-organisms are immobilized together in small alginate beads to allow close initial interaction and avoid external interference from bacterial contaminants. Indole-3-acetic acid (IAA) that is produced by the bacteria has demonstrated its role in enhancing growth rates and population size of the microalga. Th e microalgae produce and exude tryptophan and thiamine, which are the precursors of IAA formation. Carbon and nitrogen molecules are exchanged between the two partners in this synthetic mutualism. Th is close interaction positively aff ects nitrogen, phosphorus, carbohydrates, lipids and photosynthesis metabolisms. All these signifi cant metabolic changes during co-immobilization of the two micro-organisms are interlinked and off er several biotechnological applications. Th ese include waste water treatment, carbohydrate and lipid production, photosynthetic pigments and food for human and animals. Th is synthetic mutualism model is also a simple and easy way to study fundamental physiological and molecular studies.