TY - JOUR
T1 - Molecular localization of variable and conserved regions of pspA and identification of additional pspA homologous sequences in Streptococcus pneumoniae
AU - McDaniel, Larry S.
AU - Sheffield, Jeanne S.
AU - Swiatlo, Edwin
AU - Yother, Janet
AU - Crain, Marilyn J.
AU - Briles, David E.
PY - 1992/10
Y1 - 1992/10
N2 - PspA is anchored to the surface of all pneumococci by the C-terminal end of the molecule. The N-terminal half of PspA is known to be serologically variable and to be able to elicit protective immune responses. Molecular analysis with DNA probes spanning different regions of pspA was carried out to identify homologous sequences among pneumococcal isolates. At high stringency, DNA probes derived from the 3′-half of pspA (encoding the C-terminal half of PspA) hybridized to all of 37 pneumococcal isolates tested, representing 20 capsular serotypes and 12 PspA serotypes. Most strains had two sequences highly homologous to this region of pspA. Using derivatives of strain Rx1, with insertion mutations in pspA, it was possible to identify the functional pspA sequence. At 50% stringency, the 3′ pspA probes also detected lytA and additional sequences. lytA encodes autolysin and shares homology with the 3′ portion of pspA. A probe derived from the 5′-half of pspA (encoding the N-terminal half of PspA) hybridized with only 75% of strains and generally detected only one of the two sequences recognized by the 3′ probes. Thus, the 3′-half of pspA appears to contain more highly conserved sequences than the 5′-half of pspA and shares homology with several additional sequences, suggesting that the pneumococcus might make several proteins that interact with the surface by the same mechanism as PspA.
AB - PspA is anchored to the surface of all pneumococci by the C-terminal end of the molecule. The N-terminal half of PspA is known to be serologically variable and to be able to elicit protective immune responses. Molecular analysis with DNA probes spanning different regions of pspA was carried out to identify homologous sequences among pneumococcal isolates. At high stringency, DNA probes derived from the 3′-half of pspA (encoding the C-terminal half of PspA) hybridized to all of 37 pneumococcal isolates tested, representing 20 capsular serotypes and 12 PspA serotypes. Most strains had two sequences highly homologous to this region of pspA. Using derivatives of strain Rx1, with insertion mutations in pspA, it was possible to identify the functional pspA sequence. At 50% stringency, the 3′ pspA probes also detected lytA and additional sequences. lytA encodes autolysin and shares homology with the 3′ portion of pspA. A probe derived from the 5′-half of pspA (encoding the N-terminal half of PspA) hybridized with only 75% of strains and generally detected only one of the two sequences recognized by the 3′ probes. Thus, the 3′-half of pspA appears to contain more highly conserved sequences than the 5′-half of pspA and shares homology with several additional sequences, suggesting that the pneumococcus might make several proteins that interact with the surface by the same mechanism as PspA.
KW - Gram-positive surface proteins
KW - PspA or pspA
KW - Southern analysis
KW - Streptococcus pneumoniae
KW - pneumococcal surface protein A
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U2 - 10.1016/0882-4010(92)90036-N
DO - 10.1016/0882-4010(92)90036-N
M3 - Article
C2 - 1363703
AN - SCOPUS:0026937323
SN - 0882-4010
VL - 13
SP - 261
EP - 269
JO - Microbial Pathogenesis
JF - Microbial Pathogenesis
IS - 4
ER -