Affiliation:
1. Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061
Abstract
ABSTRACT
The putative carboxyl-terminal processing protease (CtpA) of
Brucella suis
1330 is a member of a novel family of endoproteases involved in the maturation of proteins destined for the cell envelope. The
B. suis
CtpA protein shared up to 77% homology with CtpA proteins of other bacteria. A CtpA-deficient
Brucella
strain (1330Δ
ctpA
), generated by allelic exchange, produced smaller colonies on enriched agar plates and exhibited a 50% decrease in growth rate in enriched liquid medium and no growth in salt-free enriched medium compared to the wild-type strain 1330 or the
ctpA
-complemented strain 1330Δ
ctpA
[pBB
ctpA
]. Electron microscopy revealed that in contrast to the native coccobacillus shape of wild-type strain 1330, strain 1330Δ
ctpA
possessed a spherical shape, an increased cell diameter, and cell membranes partially dissociated from the cell envelope. In the J774 mouse macrophage cell line, 24 h after infection, the CFU of the strain 1330Δ
ctpA
declined by approximately 3 log
10
CFU relative to wild-type strain 1330. Nine weeks after intraperitoneal inoculation of BALB/c mice, strain 1330Δ
ctpA
had cleared from spleens but strain 1330 was still present. These observations suggest that the CtpA activity is necessary for the intracellular survival of
B. suis
. Relative to the saline-injected mice, strain 1330Δ
ctpA
-vaccinated mice exhibited 4 to 5 log
10
CFU of protection against challenge with virulent
B. abortus
strain 2308 or
B. suis
strain 1330 but no protection against
B. melitensis
strain 16 M. This is the first report correlating a CtpA deficiency with cell morphology and attenuation of
B. suis
.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference55 articles.
1. Acha, P., and B. Szyfres. 1980. Zoonoses and communicable diseases common to man and animals, p. 28-45. Pan American Health Organization, Washington, D.C.
2. Basic local alignment search tool
3. Anderson, T. D., N. F. Cheville, and V. P. Meador. 1986. Pathogenesis of placentitis in the goat inoculated with Brucella abortus. II. Ultrastructural studies. Vet. Pathol.23:227-239.
4. Comparative protection of mice against virulent and attenuated strains of Brucella abortus by passive transfer of immune T cells or serum
5. Araya, L. N., P. H. Elzer, G. E. Rowe, F. M. Enright, and A. J. Winter. 1989. Temporal development of protective cell-mediated and humoral immunity in BALB/c mice infected with Brucella abortus. J. Immunol.143:3330-3337.
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