Liberation of amino acids by heterotrophic nitrogen fixing bacteria

Abstract

Large amounts of amino acids are produced by nitrogen-fixing bacteria such as Azotobacter, Azospirillum, Rhizobium, Mesorhizobium and Sinorhizobium when growing in culture media amended with different carbon and nitrogen sources. This kind of bacteria live in close association with plant roots enhanced plant growth mainly as a result of their ability to fix nitrogen, improving shoot and root development suppression of pathogenic bacteria and fungi, and increase of available P concentration. Also, it has been strongly evidenced that production of biologically substances such as amino acids by these rhizobacteria are involved in many of the processes that explain plant-grown promotion. This paper reviews literature concerning amino acids production by nitrogen-fixing bacteria. The role of amino acids in microbial interactions in the rhizosphere and establishment of plant bacterial association is also discussed.

Genome‐wide analysis of bacterial determinants of plant growth promotion and induced systemic resistance by Pseudomonas fluorescens

“…Most of the 21 mutants were deficient in the biosynthesis of specific amino acids. The role of amino acids in rhizobacteria-plant interactions is not well studied, although some amino acids such as methionine and tryptophan may act in soil as precursors for the biosynthesis of the phytohormones ethylene and indole-3-acetic acid, respectively (Murcia et al, 1997;Gonz alez-L opez et al, 2005). What the role is of these and other amino acids (histidine, valine, leucine and isoleucine) in root colonization and Pf.SS101-Arabidopsis interactions is yet unknown.…”

Gold leaching in cyanide-starved copper solutions in the presence of glycine

“…Therefore, the main aim of this work is to investigate the effect of adding glycine on the enhancement of gold dissolution in solutions containing different copper-cyanide species, based on earlier research by the authors looking at the solubility of copper minerals and gold in an alkaline glycine-peroxide system Eksteen, 2014, 2015). Glycine is one of the simplest and cheapest amino acids among the available 20 amino acids; it can be easily produced industrially or derived as a by-product of different microorganisms (González-lópez et al, 2005). The presence of glycine can also enhance the solubility of gold in aqueous solutions as the main lixiviant of dissolving gold due to its complexing action with gold (Brown and Smith, 1982;Aylmore, 2005;Eksteen and Oraby, 2015).…”

Inoculation of sugarcane with Pantoea sp. increases amino acid contents in shoot tissues; serine, alanine, glutamine and asparagine permit concomitantly ammonium excretion and nitrogenase activity of the bacterium

“…Moreover, the amino acid concentrations in sugarcane change in response to the inoculation with G. diazotrophicus (Tejera et al, 2006). N-fixing bacteria living in close association with plants release normally amino acids but it depends on several factors (González-López et al, 2005). The role of amino acids in sugarcane-endophyte interaction needs to be elucidated.…”