Recombinant plants release

Parks, T. D., Leuther, K. K., Howard, E. D., Johnston, S. A. and Dougherty, W. G. (1994). Release of proteins and peptides from fusion proteins using a recombinant plant virus proteinase. Anal. Biochem. 216,413-417. 

The oleosin fusion procedure was used for the purification of the commercially valuable plant-based blood anticoagulant hirudin in transgenic Brassica carinata and Brassica napus. Hirudin, a natural protein from the medicinal leech Hirudo medicinalis, is superior to other anticoagulants such as heparin. Recombinant hirudin was cleaved from oil-bodies using endoproteinase Factor Xa. Released hirudin was biologically active, as determined by a colorimetric thrombin inhibition assay. 

An early attempt to produce a recombinant human 29-amino acid antimicrobial peptide SMAP29 in tobacco was reported by Morassutti et al. (2002) who used a chitin-binding domain for purification and an associated intein cleavage system to release the peptide. Expression levels appeared to be low, with the peptide associated with plant proteins. Upon electrophoretic separation, the peptide displayed the expected immunological and biological activites. 

The principal purpose of plant containment is to avoid the unintentional transmission of a recombinant DNA-containing plant genome, including nnclear or organelle hereditary material or release of recombinant DNA-derived organisms associated with plants. 

This document focuses on the subset of recombinant-DNA plants intended for commercialisation, unconfined or full release that is subject to risk/safety assessments. 

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