Proteins

Proteins are the primary means of expressing the genetic information coded in DNA. These polymers are based on building blocks of amino acid monomers whose sequence is predetermined by a genetic template. The sequence diversity of proteins is responsible for the wide array of functions performed by proteins in living organisms (OTA, 1993). A variety of plant proteins might one day be commercially exploited as materials, but current understanding of the structural properties of most plant proteins is limited.

Zein is perhaps the best understood plant protein. It has been given the most interest due to its ability to form fibers and films that are tough, glossy, and resistant to grease and scuffing. The Virginia-Carolina Corporation once produced 5 million pounds of Zein fiber before shifting to comparable synthetic fibers. Today Zein is used as a water-impermeable coating for pharmaceutical tablets, binding for bottle-cap liners, and a shellac substitute. The industrial usefulness and merits of Zein have stimulated continual examination of proteins (Wall and Paulis, 1978).