Production of double repeated B subunit of Shiga toxin 2e at high levels in transgenic lettuce plants as vaccine material for porcine edema disease.
Pig edema disease is a bacterial disease caused by enterohemorrhagic Escherichia coli. E. coli produces Shiga toxin 2e (Stx2e), which is composed of one A subunit (Stx2eA) and five B subunits (Stx2eB). We previously reported production of Stx2eB in lettuce plants as a potential edible vaccine (Matsui et al. in Biosci Biotechnol Biochem 73:1628-1634, 2009). However, the accumulation level was very low, and it was necessary to improve expression of Stx2eB for potential use of this plant-based vaccine. Therefore, in this study, we optimized the Stx2eB expression cassette and found that a double repeated Stx2eB (2× Stx2eB) accumulates to higher levels than a single Stx2eB in cultured tobacco cells. Furthermore, a linker peptide between the two Stx2eB moieties played an important role in maximizing the effects of the double repeat. Finally, we generated transgenic lettuce plants expressing 2× Stx2eB with a suitable linker peptide that accumulate as much as 80 mg per 100 g fresh weight, a level that will allow us to use these transgenic lettuce plants practically to generate vaccine material.
Matsui
Takeshi
T
Advanced Technology Research Laboratories, Idemitsu Kosan Co., Ltd., 1280 Kamiizumi, Sodegaura-shi, Chiba, 299-0293, Japan.
Takita
Eiji
E
Sato
Toshio
T
Aizawa
Michie
M
Ki
Misa
M
Kadoyama
Yumiko
Y
Hirano
Kenji
K
Kinjo
Satoko
S
Asao
Hiroshi
H
Kawamoto
Keiko
K
Kariya
Haruko
H
Makino
Sou-Ichi
S
Hamabata
Takashi
T
Sawada
Kazutoshi
K
Kato
Ko
K
D000818:Animals; D001428:Bacterial Vaccines / Q000235:genetics* / Q000627:therapeutic use; D004488:Edema Disease of Swine / Q000628:therapy*; D054324:Enterohemorrhagic Escherichia coli; D005822:Genetic Vectors; D018545:Lactuca / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics; D022641:Shiga Toxin 2 / Q000096:biosynthesis* / Q000235:genetics / Q000627:therapeutic use*; D013552:Swine; D022462:Vaccines, Edible / Q000235:genetics / Q000627:therapeutic use
D001428:Bacterial Vaccines; D021122:Protein Subunits; D022641:Shiga Toxin 2; D022462:Vaccines, Edible