Expression of
Colonization Factor Antigen I of Enterotoxigenic Escherichia
coli in Shigella flexneri 2a T32
ZHANG Bo2,
LI Shu-Qin1, CHEN Guan-Jun2, HUANG Cui-Fen１, ZHANGZhao-Shan1*
( 1Beijing Institute of Biotechnology, Beijing 100071,
China; 2State Key Laboratory of Microbial Technology,
Shandong Univercity, Jinan 250100, China )
Abstract A
host plasmid lethal balancing system was constructed based on asd gene
in an avirulent strain of S.flexneri to express colonization factor
antigen I(CFA-I) of enterotoxigenic Escherichia coli.The results of
Western blotting suggested that avirulant strain of S.flexneri Fwl01 expressed
CFA-I steadily. Examination of negatively stained preparation of cultures by
electron microscopy showed that S.flexneri Fwl01 carrying the plasmid
pZHY21 had thick pili on its surface. Antibodies against CFA-I were decteted in
sera of mice immunized with recombinant bacteria either orogastrically (o.g.)
or intranasally(i.n.); simultaneously sIgA against CFA-I was also decteted in
the intestine. This work is helpful for constructing multivalent reombinant
vaccine for prevention of bacterial diarrhea.
Key words ETEC; CFA-I; host-plasmid
balancing system; Shigella flexneri
*Corresponding author: Tel,
86-10-63834140; Fax, 86-10-63833521; e-mail, [email protected]