Amino Acids

, Volume 39, Issue 4, pp 979–989 | Cite as

High-lysine maize: the key discoveries that have made it possible

  • R. A. Azevedo
  • P. Arruda
Review Article


Forty-five years ago, a paper published by Mertz et al. (Science 145:279–280, 1964) initiated a revolution in the history of plant protein quality and affected dramatically the study of cereal crop storage proteins. The observation of the high lysine content of the endosperm of the opaque-2 (o2) maize mutant was a key factor in bringing about a new concept in the production of cereal seeds with a high nutritional value. It has been a long and very interesting road with astonishing results over these 45 years. We are now probably about to see the release of commercially engineered high-lysine maize lines. We have decided to pinpoint some key contributions to the science behind high-lysine plants and concentrated on the research done on maize, which is possibly the most complete and simple example to illustrate the advances achieved. However, studies on other plant species such as barley and model species such as tobacco are totally relevant and will be briefly addressed.


Aspartic acid Corn Isoleucine Lysine Maize Methionine Threonine 



We are indebted to Professor Peter J. Lea for a critical reading of the manuscript. The authors wish to thank the continuous support over the years of the Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP-Brazil) and the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq-Brazil).


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© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Departamento de Genética, Escola Superior de Agricultura Luiz de QueirozUniversidade de São PauloPiracicabaBrazil
  2. 2.Centro de Biologia Molecular e Engenharia GenéticaUniversidade Estadual de CampinasCampinasBrazil
  3. 3.Departamento de Genética e Evolução, Instituto de BiologiaUniversidade Estadual de CampinasCampinasBrazil

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