Enhancement of the free amino acid and protein content of cassava storage roots and evaluation of root-specific promoters in cassava
Year: 2011
Type: article
Abstract: Cassava is an important staple crop for millions of people around the world in particular in Sub-Saharan Africa.Cassava is preferred given its many agronomical attributes such as ability to grow in poor soils and drought resistance.Cassava storage roots are also a good source of calories (starch), however, they are deficient in protein and other micronutrients such as iron and zinc.Protein malnutrition is widespread in the regions were cassava is widely consumed and consumption of cassava as a staple has been linked to reduced protein intake in the diet.A cassava storage root with higher protein could potentially impact the nutrition and well being of millions people.There are several proposed strategies to increase the protein and free amino acid content in crops such as modification of the amino acid biosynthetic pathways and over expression of native storage proteins.In this thesis we propose two different approaches for increasing free amino acids and protein.One approach was to increase nitrate assimilation through the expression of a mutated nitrate reductase.Nitrate reduction to nitrite is followed by a further reduction to ammonium which can be readily incorporated into amino acids.A rate limiting step in nitrate metabolism is the reduction of nitrate to nitrite by nitrate reductase.This enzyme is highly regulated, however, it has been observed that through mutation of a key regulatory serine the enzyme remains active and the assimilation of nitrate increases resulting in increased free amino acid levels.In
Author: Elisa Leyva-Guerrero
Institution: The Ohio State University
Language: English
Topic: Cassava research and cyanide
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2462475223