TY - JOUR
T1 - Biogenesis of Yersinia pestis PsaA in recombinant attenuated Salmonella Typhimurium vaccine (RASV) strain
AU - Torres-Escobar, Ascención
AU - Juárez-Rodríguez, María Dolores
AU - Curtiss, Roy
PY - 2010/1
Y1 - 2010/1
N2 - Yersinia pestis PsaA is an adhesin important for the establishment of bacterial infection. PsaA synthesis requires the products of the psaEFABC genes. Here, by prediction analysis, we identified a PsaA signal sequence with two signal peptidase (SPase) cleavage sites, type-I and type-II (SPase-I and SPase-II). By Edman degradation and site-directed mutagenesis, the precise site for one of these Spase-I PsaA cleavage sites was located between alanine and serine at positions 31 and 32, respectively. Yersinia pestis psaA expression and the role of the PsaB and PsaC proteins were evaluated in recombinant attenuated Salmonella Typhimurium vaccine strains. PsaA was detected in total extracts as a major 15-kDa (mature) and 18-kDa (unprocessed) protein bands. PsaA synthesis was not altered by a ΔA31-ΔS32 double-deletion mutation. In contrast, the synthesis of PsaA (ΔA31-ΔS32) in Y. pestis and delivery to the supernatant was decreased. Otherwise, substitution of the amino acid cysteine at position 26 by valine involved in the SPase-II cleavage site did not show any effect on the secretion of PsaA in Salmonella and Yersinia. These results help clarify the secretion pathway of PsaA for the possible development of vaccines against Y. pestis.
AB - Yersinia pestis PsaA is an adhesin important for the establishment of bacterial infection. PsaA synthesis requires the products of the psaEFABC genes. Here, by prediction analysis, we identified a PsaA signal sequence with two signal peptidase (SPase) cleavage sites, type-I and type-II (SPase-I and SPase-II). By Edman degradation and site-directed mutagenesis, the precise site for one of these Spase-I PsaA cleavage sites was located between alanine and serine at positions 31 and 32, respectively. Yersinia pestis psaA expression and the role of the PsaB and PsaC proteins were evaluated in recombinant attenuated Salmonella Typhimurium vaccine strains. PsaA was detected in total extracts as a major 15-kDa (mature) and 18-kDa (unprocessed) protein bands. PsaA synthesis was not altered by a ΔA31-ΔS32 double-deletion mutation. In contrast, the synthesis of PsaA (ΔA31-ΔS32) in Y. pestis and delivery to the supernatant was decreased. Otherwise, substitution of the amino acid cysteine at position 26 by valine involved in the SPase-II cleavage site did not show any effect on the secretion of PsaA in Salmonella and Yersinia. These results help clarify the secretion pathway of PsaA for the possible development of vaccines against Y. pestis.
KW - Chaperone protein
KW - Signal peptidase
KW - Usher protein
KW - Yersinia enterocolitica
KW - Yersinia pseudotuberculosis
UR - http://www.scopus.com/inward/record.url?scp=74049128334&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=74049128334&partnerID=8YFLogxK
U2 - 10.1111/j.1574-6968.2009.01827.x
DO - 10.1111/j.1574-6968.2009.01827.x
M3 - Article
C2 - 20002189
AN - SCOPUS:74049128334
SN - 0378-1097
VL - 302
SP - 106
EP - 113
JO - FEMS Microbiology Letters
JF - FEMS Microbiology Letters
IS - 2
ER -