Premium
Transgenic plant production of Cyanovirin‐N, an HIV microbicide
Author(s) -
Sexton Amy,
Drake Pascal M.,
Mahmood Naheed,
Harman Sarah J.,
Shattock Robin J.,
Ma Julian KC.
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fj.05-4742fje
Subject(s) - microbicide , transgene , recombinant dna , genetically modified crops , western blot , biology , nicotiana tabacum , human immunodeficiency virus (hiv) , gene , microbiology and biotechnology , virology , biochemistry
Cyanovirin‐N (CV‐N) is a microbicide candidate that inactivates a wide range of HIV strains by binding to gp120. Production of CV‐N, or any protein microbicide, needs to be at extremely high levels and low cost to have an impact on global health. Thus, it is unlikely that fermentor‐based systems will be suitable, including recombinant E. coli , where CV‐N aggregates and dimers have consistently been found. Transgenic plants may provide a suitable expression system for protein microbicides, as production can be easily and economically scaled up. Here, Nicotiana tabacum was transformed with a gene encoding CV‐N to explore proof of concept for the production of CV‐N in transgenic plants. Plant‐derived rCV‐N was recoverable at levels of 130 ng/mg of fresh leaf tissue, or at least 0.85% of total soluble plant protein. Western blot analysis demonstrated that virtually all of the rCV‐N was expressed in the desired monomeric form. Functionality was demonstrated by specific binding to gp120 and protection of T‐cells from in vitro HIV infection. Hydroponic culturing of transgenic plants demonstrated CV‐N rhizosecretion at levels of 0.64 μg/ml hydroponic media after 24 days. Therefore, we suggest that transgenic plants have the potential to provide strategies for large‐scale protein microbicide production.