Open AccessTransgenic chloroplasts are efficient sites for high‐yield production of the vaccinia virus envelope protein A27L in plant cells †
Author(s) -
Rigano M. Manuela,
Manna Carmela,
Giulini Anna,
Pedrazzini Emanuela,
Capobianchi Maria,
Castilletti Concetta,
Di Caro Antonino,
Ippolito Giuseppe,
Beggio Paola,
De Giuli Morghen Carlo,
Monti Luigi,
Vitale Alessandro,
Cardi Teodoro
Publication year - 2009
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/j.1467-7652.2009.00425.x
Subject(s) - biology , vaccinia , virology , nicotiana benthamiana , virus , chloroplast , recombinant dna , gene , biochemistry
Summary Orthopoxviruses (OPVs) have recently received increasing attention because of their potential use in bioterrorism and the occurrence of zoonotic OPV outbreaks, highlighting the need for the development of safe and cost‐effective vaccines against smallpox and related viruses. In this respect, the production of subunit protein‐based vaccines in transgenic plants is an attractive approach. For this purpose, the A27L immunogenic protein of vaccinia virus was expressed in tobacco using stable transformation of the nuclear or plastid genome. The vaccinia virus protein was expressed in the stroma of transplastomic plants in soluble form and accumulated to about 18% of total soluble protein (equivalent to approximately 1.7 mg/g fresh weight). This level of A27L accumulation was 500‐fold higher than that in nuclear transformed plants, and did not decline during leaf development. Transplastomic plants showed a partial reduction in growth and were chlorotic, but reached maturity and set fertile seeds. Analysis by immunofluorescence microscopy indicated altered chlorophyll distribution. Chloroplast‐synthesized A27L formed oligomers, suggesting correct folding and quaternary structure, and was recognized by serum from a patient recently infected by a zoonotic OPV. Taken together, these results demonstrate that chloroplasts are an attractive production vehicle for the expression of OPV subunit vaccines.