Purpose

Improvement of the protein quality of major crops has been a concern for plant breeders. Human food and animal feed derived from corn, soybeans and most cereals are deficient in several of the essential amino acids required.

Example: Corn is a preferred animal feed because it is a low cost energy source. However, it is deficient in lysine, methionine and tryptophan. Lysine as a supplement in animal feed costs producers approximately $500 million dollars a year. Were the quantities of lysine and methionine in crops to be increased to remove the need for supplementation, the added value will be in the millions of dollars per year.

Project

The objective of the proposed research is to develop a biotechnological means to improve the protein quality of corn by increasing the quantity of lysine and tryptophan in seeds, without affecting yield or other desirable traits. Varieties of corn have been found which produce kernels with higher lysine and tryptophan. However, they have not been adopted by producers because of reduced yield or fertility, greater sensitivity to pests and increased kernel fragility.

Objectives

1. Screen transgenic corn events and select those with the highest levels of lysine in their seeds.
2. Introduce DNA sequences conferring enhanced lysine trait into elite germplasm and select those with the highest levels of lysine and protein and kernel quality.
3. Characterize high lysine corn for introduced DNA and for novel metabolites, proteins and allergens that might affect safety and public acceptance.

Impact

Savings in supplemental feed of several million dollars per year.