TY  - JOUR
A1  - Hacker, Jörg
A1  - Kestler, H.
A1  - Hoschützky, H.
A1  - Jann, K.
A1  - Lottspeich, F.
A1  - Korhonen, T. K.
T1  - Cloning and characterization of the S fimbrial adhesin (SfaII) complex of an Escherichia coli O18:K1 meningitis isolate
N2  - S fimbrial adbesins (Sfa), which are able to recognize sialic acid-containing receptors on eukaryotic cells, are produced by Escherichia coli strains causing urinary tract infections or newbom meningitis. We recently described tbe cloning and molecular cbaracterization of a determinant, termed sftJI, from the chromosome of an E. coli urinary tract infection strain. Herewe present data conceming a S fimbria-specific gene duster, designated sfall, of an E. coli newbom meningitis strain. Like tbe Sfal complex, Sfall consists of tbe major subunit protein SfaA (16 kDa) and the minor subunit proteins SfaG (17 kDa), SfaS (15 kDa), and SfaH (29 kDa). The genes encoding tbe subunit proteins of Sfall were identified and sequenced. Their protein sequences were calculated from the DNA sequences and compared with tbose of the Sfal complex subunits. Altbough the sequences ofthe two major SfaA subunits ditf'ered markedly, tbe sequences ofthe minor subunits sbowed only a few amino acid exchanges (SfaG, SfaH) or were completely identical (SfaS). The introduction of a site-specific mutation into the gene sfaSII and subsequent analysis of an SfaS-negative clone indicated that sfaSII codes for the sialic acid-specific adhesin of tbe meninigitis isolate. These data were confirmed by tbe isolation and characterization of tbe SfaSII protein and the determination of its N-terminal amino acid sequence. The identity between the sialic acid-specific adhesins of Sfal and Sfall revealed that difl'erences between the two Sfa complexes with respect to tbeir capacities to agglutinate erythrocytes must result from sequence alterations of subunit proteins other tban SfaS.
KW  - Infektionsbiologie
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59853
ER  - 
TY  - JOUR
A1  - Schmoll, T.
A1  - Hoschützky, H.
A1  - Morschhäuser, J.
A1  - Lottspeich, F.
A1  - Jann, K.
A1  - Hacker, Jörg
T1  - Analysis of genes coding for the Sialic acid-binding adhesin and two other minor fimbrial subunits of the S-fimbrial adhesin determinant of Escherichia coli
N2  - The S flmbrial adhesln (Sfa) enables Esch richla colito attach to slalfc acld-containing receptor molecules of eukaryotJc cells. As prevlously reported, the genetlc determinant coding for the Sfa of an E. co/1 06 strain was cloned, the gene codlng for the major fimbrfal subunit was ldentlfled and sequenced and th.e S speclflc adhesin was detected. Here we present evidence that ln addltlon to the major subunit proteln SfaA three other minor subunit proteins, SfaG (17 kD), SfaS (14kD) and SfaH (31 kD) can be isolated from the S..speclfic flmbrial adhesln complex. The genes coding for these minor subunits were ldenblied, mutagenlzed separately and sequenced. Using haemagglutlnatton tests. electron-microscopy and quantitative ELISA assays with monoclonal anti-SfaA and anti-SfaS antlbodles the functlons of the minor subunlts were determined. lt was determlned that SfaS ls ldentlcal to the S-specific adhesln; whlch also plays a role ln deterrninatlon of the degree of fimbri· ation ofthe cell. The mlnor subunit SfaH also had some Jnfluence on the Ievei of fimbrlation of the cell. while StaG ls necessary for full expression of S·specific binding. lt was further shown that the amino-terminal proteln sequence of the isolated SfaS profein was identJcal to the proteln sequence calculated from the DNA sequence of the sfaS gene locus.
KW  - Infektionsbiologie
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59585
ER  -