Amino Acid Uptake in Arbuscular Mycorrhizal Plants

Abstract

We examined the extent to which arbuscular mycorrhizal (AM) fungi root improved the acquisition of simple organic nitrogen (ON) compounds by their host plants. In a greenhouse-based study, we used quantum dots (fluorescent nanoparticles) to assess uptake of each of the 20 proteinaceous amino acids by AM-colonized versus uncolonized plants. We found that AM colonization increased uptake of phenylalanine, lysine, asparagine, arginine, histidine, methionine, tryptophan, and cysteine; and reduced uptake of aspartic acid. Arbuscular mycorrhizal colonization had the greatest effect on uptake of amino acids that are relatively rare in proteins. In addition, AM fungi facilitated uptake of neutral and positively-charged amino acids more than negatively-charged amino acids. Overall, the AM fungi used in this study appeared to improve access by plants to a number of amino acids, but not necessarily those that are common or negatively-charged.

The effect of different nitrogen sources on the symbiotic interaction between Sorghum bicolor and Glomus intraradices : Expression of plant and fungal genes involved in nitrogen assimilation

“…genes coding for N assimilation (GiGS2 and GiGluS) and arginine biosynthesis (GiCPS, GiASS and GiAL), was higher in the ERM than in the IRM and independent of the N source. Conversely, the expression of genes coding for arginine breakdown (GiCAR, GiURE, GiOAT1 and GiOAT2) was higher in the IRM than in the ERM, corroborating earlier findings (Leigh et al, 2009;Whiteside et al, 2012). In the IRM, a high specific activity of OAT and URE had already been measured (Govindarajulu et al, 2005).…”

Role of Arbuscular Mycorrhizal Fungi in the Nitrogen Uptake of Plants: Current Knowledge and Research Gaps

“…While some amino acids such as glycine, serine and glutamine competed strongly with proline for this transporter, positively charged amino acids such as arginine, histidine and lysine were only poor competitors. The mycorrhizal colonization of Sorghum bicolor led to an increase in the uptake of phenylalanine, methionine, asparagine, tryptophane, and cysteine, but also increased the uptake of the charged amino acids arginine, lysine, and histidine [113]. Other studies demonstrated that arginine can be taken up by the ERM and that arginine is not metabolized during its transport from the ERM to the IRM [50].…”

Phosphate Solubilizing Bacillus megaterium mj1212 Regulates Endogenous Plant Carbohydrates and Amino Acids Contents to Promote Mustard Plant Growth

“…The uptake of nitrogen by plants in the form of amino acids has been determined as a widespread ecological phenomenon [20]. The microbial colonization in plants strongly influences amino acid uptake [21]. The rhizobacteria help to fix the atmospheric nitrogen in soil.…”