Caryedes brasiliensis

Examination of this question with the tobacco hornworm, an insect known to be canavanine-sensitive (this insect normally feeds on canavanine-free plants) revealed that it readily incorporates [ C]canavanine into its newly synthesized proteins. Caryedes brasiliensis. however, very effectively avoids the production of such radiolabeled proteins. When the arginyl- RNA synthetase activity of these insects was compared, tobacco hornworm larvae readily activated canavanine while the larvae of the bruchid beetle possess an arginyl- tRNA synthetase with a marked ability to discriminate between arginine and its structural analogue (22). 

The generalist feeding insect Heliothis virescens, the tobacco budworm, has relatively high resistance to canavanine but not to a number of other nonprotein amino acids (Berge et al., 1986). In this case, canavanine (37) was shown to be neither excreted nor sequestered, but rather metabolized by the insect. In Caryedes brasiliensis, Sternechus tuberculatus... 

The bruchid beetle Caryedes brasiliensis, for instance, a specialized insect living on canavanine-containing seeds, possesses an arginyl-tRNA synthetase that, in contrast to the enzymes of most other organisms, discriminates against canavanine. Moreover the beetle is able to degrade cana-vanine to canaline and urea and to hydrolyze the latter compound to ammonia. 

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