L-(+)-(S)-Canavanine is a non-proteinogenic amino acid found in certain leguminous plants. It is structurally related to the proteinogenic α-amino acid L-arginine, the sole difference being the replacement of a methylene bridge (-- unit) in arginine with an oxa group (i.e., an oxygen atom) in canavanine. Canavanine is accumulated primarily in the seeds of the organisms which produce it, where it serves both as a highly deleterious defensive compound against herbivores and a vital source of nitrogen for the growing embryo (see also L-canaline). The mechanism of canavanine's toxicity is that organisms that consume it typically mistakenly incorporate it into their own proteins in place of L-arginine, thereby producing structurally aberrant proteins that may not function properly. The toxicity of canavanine may be enhanced under conditions of protein starvation, and canavanine toxicity  resulting from consumption of Hedysarum alpinum seeds , which contain quantities of canavanine around 1\% , has been implicated in the death of Christopher McCandless  . (McCandless was the subject of Jon Krakauer's book (and subsequent movie) Into the Wild).
L-(+)-(S)-Canavanine is a non-proteinogenic amino acid found in certain leguminous plants. It is structurally related to the proteinogenic α-amino acid L-arginine, the sole difference being the replacement of a methylene bridge (-- unit) in arginine with an oxa group (i.e., an oxygen atom) in canavanine. Canavanine is accumulated primarily in the seeds of the organisms which produce it, where it serves both as a highly deleterious defensive compound against herbivores and a vital source of nitrogen for the growing embryo (see also L-canaline). The mechanism of canavanine's toxicity is that organisms that consume it typically mistakenly incorporate it into their own proteins in place of L-arginine, thereby producing structurally aberrant proteins that may not function properly. The toxicity of canavanine may be enhanced under conditions of protein starvation, and canavanine toxicity , resulting from consumption of Hedysarum alpinum seeds with a concentration of 1.2\% canavanine weight/weight , has been implicated in the death of a malnourished Christopher McCandless.Krakauer, J., et al. (2015). "Presence of l-canavanine in Hedysarum alpinum seeds and its potential role in the death of Christopher McCandless." Wilderness Environmental Medicine . (McCandless was the subject of Jon Krakauer's book (and subsequent movie) Into the Wild).
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, which contain quantities of canavanine around 1\%
with a concentration of 1.2\% canavanine weight/weight
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Christopher McCandless
a malnourished Christopher McCandless.Krakauer, J., et al. (2015). "Presence of l-canavanine in Hedysarum alpinum seeds and its potential role in the death of Christopher McCandless." Wilderness
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Environmental Medicine