Biofortification of Tomato (Solanum lycopersicum) Fruit with the Anticancer Compound Methylselenocysteine Using a Selenocysteine Methyltransferase from a Selenium Hyperaccumulator

• Published in: Journal of agricultural and food chemistry Vol. 59; no. 20; pp. 10987 - 10994
• Main Authors: Brummell, David A, Watson, Lyn M, Pathirana, Ranjith, Joyce, Nigel I, West, Phillip J, Hunter, Donald A, McKenzie, Marian J
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 26.10.2011
• Subjects: amino acid derivatives; animals; anticarcinogenic activity; Antineoplastic Agents - analysis; Antineoplastic Agents - metabolism; biofortification; Biological and medical sciences; Chemical Aspects of Biotechnology/Molecular Biology; complementary DNA; Cysteine - analogs & derivatives; Cysteine - analysis; Cysteine - metabolism; Food industries; Food, Fortified - analysis; Fruit - chemistry; Fruit - metabolism; Fruit and vegetable industries; fruiting; Fundamental and applied biological sciences. Psychology; Gene Expression; gene overexpression; heat stability; hyperaccumulators; leaves; Lycopersicon esculentum - metabolism; mass spectrometry; Methyltransferases - genetics; Organoselenium Compounds - analysis; Organoselenium Compounds - metabolism; Plants, Genetically Modified - metabolism; roots; Selenic Acid; selenium; Selenium - analysis; Selenium - metabolism; Selenium Compounds - administration & dosage; Selenium Compounds - metabolism; selenocysteine; Selenocysteine - analogs & derivatives; Sodium Selenite - administration & dosage; Sodium Selenite - metabolism; Solanum lycopersicum; tomato juice; tomatoes; transgenic plants; Methylselenocysteine; selenocysteine methyltransferase; tomato; anticancer compounds; Solanum lycopersicum; transgene expression; Antineoplastic agent; Vegetables; Fruit; Tomato; Inorganic element; Dicotyledones; Angiospermae; Spermatophyta; Solanaceae; Solanum; Selenium
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf202583f

Methylselenocysteine (MeSeCys) is an amino acid derivative that possesses potent anticancer activity in animals. Plants that can tolerate growth on soils with high Se content, known as Se hyperaccumulators, do so by converting inorganic Se to MeSeCys by the enzyme selenocysteine methyltransferase (SMT). A cDNA encoding the SMT from a Se hyperaccumulator was overexpressed in tomato (Solanum lycopersicum). Transgenic plants were provided with selenite or selenate to the roots during fruit development, and liquid chromatography–mass spectrometry was used to show that MeSeCys accumulated in the fruit but not in the leaves. Depending on the transgenic line and Se treatment, up to 16% of the total Se in the fruit was present as MeSeCys. MeSeCys was produced more effectively from selenite on a percentage conversion basis, but greater accumulation of MeSeCys could be achieved from selenate due to its better translocation from the roots. MeSeCys was heat stable and survived processing of the fruit to tomato juice.