TY - JOUR A1 - Munoa, F. A1 - Hacker, Jörg A1 - Juarez, A. T1 - Characterization of a chromosomal mutant that blocks hemolysin excretion in Escherichia coli N2 - We analyzed an Escherichia coli strain which harbours a chromosomal mutation that blocks the hemolysin excretion. Compartmentation studies showed that hemolysin accumulates in the cytoplasm and not in the periplasm. The mutation did not affect the SDS-PAGE protein pattern of the outer membrane, although some alterations were apparent in the periplasmic protein pattern. The mutant strain, E. coli Hsb-1 also failed to export a cloned fimbrial adhesin. The mutation maps in the min. 3.5 of the E. coli genetic map. KW - Infektionsbiologie KW - Hemolysin excretion KW - Escherichia coli KW - Mutant Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59534 ER - TY - JOUR A1 - Hacker, Jörg A1 - Ulmer, E. A1 - Fasske, E. A1 - Schmidt, G. T1 - Isolation and characterization of coliphage Omega18A specific for Escherichia coli O18ac strains N2 - The bactedophage Q18A, specific for Escherichia coli 018ac srrains, was isolated frorn sewage. The results of host range and conjugation experiments showed that the sensitivity of bacteria to the phage is associated with rhe presence of 018ac antigens. With sorne of rhe 018 strains rhe phage Q18A produces clear Iysis on bacterial lawns only when applied at a high multiplicity and moreover the phage does not multiply. With rhe help of the phage Ql8A, E. coli 0 18ac strains could be divided inro rwo serologically clistinct subgroups called 018A and 018A1• E. coli strains belanging to the sugroup 0 ISAare sensitive to phage Q t8A wheteas bacteria of subgroup A1 are resistanr. N2 - Der Bakteriophage Q18A, der spezifisch Escherichia coli 018ac Bakterien lysierr, wurde aus Abwasser isoliert. Die Untersuchungen des Wirtsbereichs und Konjugationsversuche zeigten, daß die Sensitivität der Bakterien gegenüber dem Phagen mit dem Vorhandensein des 0 '18ac Antigens assoziiert ist. Bei eir1igen 0 18 Stämmen wird nur bei Anwendung hoher Phagenkonzentrationen eine klare Lysis auf dem Bakterienrasen erzeugt. Darüber hinaus läßt sich der Phage auf diesen Stämmen nicht vermehren. Mit Hilfe des Phagen Q l8A konnten E, wli 0 18ac Stämme in zwei serologische Subgruppen unteneilt werden, die als 0 lHA und 0 l8A 1 bezeichnet werden. E. coli Bakterien der Subgruppe 0 ISA sind gegenüber dem Phagen Ql8A sensitiv und diejenigen der Subgruppe 0 18A 1 sind resistent. KW - Escherichia coli Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-73001 ER - TY - JOUR A1 - Schmoll, T. A1 - Hacker, Jörg A1 - Goebel, W. T1 - Nucleotide sequence of the sfaA gene coding for the S fimbrial protein subunit of Escherichia coli N2 - The sfaA gene of the uropathogenic Escherichia coli 06 strain 536, which is responsible for the determination of the S fimbrial protein subunit, was sequenced. The structural gene codes for a polypeptide of 180 amino acids including a 24-residue N-terminal signal sequence. A size of 15.95 kDa was calculated for the processed SfaA protein. The nucleotide and deduced amino acid sequences show significant homology to those of the F1C fimbria and, to a lesser extent, of the mannose- sensitive hemagglutinating fimbria (FimA, PilA). Only week homology toP fimbriae subunits (F72 , Pap) was found. KW - Infektionsbiologie KW - Escherichia coli KW - Fimbria KW - (Nucleotide sequence KW - sfaA gene) Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59480 ER - TY - JOUR A1 - Hacker, Jörg A1 - Schrettenbrunner, A. A1 - Schröter, G. A1 - Schmidt, G. A1 - Düvel, H. A1 - Goebel, W. T1 - Characterization of Escherichia coli wild-type strains by means of agglutination with antisera raised against cloned P-, S- and MS-fimbriae antigens, hemagglutination, serotyping and hemolysin-production N2 - E. coli stcains isolated from patients with urinary tcact infecrions (UTn very often possess mannose"sensitive (MS) and mannose-resistant (MR) adherence facmrs (fimbriae). According to their receptor specificity the mannose-resistant adhesins can be divided inm several types, P, S, M and X. We have cloned rhe determinants of rhree groups of UTI E. coli adhesins, MS, p and S, and prepared specific aorisera against the fimbriae antigens. 189 hernagglutination (HA+) -positive stcains, 96 fecal isolates and 93 strains isoJated from UTI . have been tesred with rhese specific antisera and further characterized by receptor specific : HA, HA parteras and further of rhe "common 0 serogroups" 01, 02, 04, 06, 07, 08, 018, ' 025, 075, most prevalenr in UTI, and hemolysin production. · 68 (73 %) of the UTI srrains a.nd 50 (52%) of the fecal isolates showed P-receptor specificiry; 16 (17%) of the uropathogenic bacteria and 33 (34%) of the fecal strains exhibited S, M or X-fimbriae antigens. 24% of rhe P-hemagglutinating (P+) strains reacted wirb P (F8)-specific antiserum. In contrast, more than three quaner of the s+-srrains were agglutinated by S-specific antiserum. HA-pattern VJ and 018 amigen were found to be associared with P-fimbriae strains, wbereas HA-pattern V and VII and the 0 anrigens 02 (M-type), 06 and 018 (5-type) occurred most frequently in p- -strains. A high percentage of P-fimbriated strains showed mannose-sensitive hemagglurination and hemolysin production. N2 - E. co/i-Stämme, die von Patienten mit Urogenitaltraktinfektionen (UTI) isoliert werden, weisen oftmals Mannose-sensitive (MS) und Mannose-resistente (MR) Adhärenzfaktoren (Fimbrien) auf. Entsprechend ihrer Rezeptorspezifität können die MR-Adhäsine in verschiedene Gruppen, P, S, M und X unterteilt werden. Vor kurzem haben wir die Determinanten von drei Gruppen der UTI E. coli-Adhäsine, MS, P und S, kloniert und spezifische Antiseren gegen diese Fimbrienantigene hergestellt. 189 Hämagglutinations (HA +)-positive Stämme,. 96 Isolate aus Stuhlproben und 93 Stämme von Patienten mit UTl, wurden mit diesen Fimbrienantigen-spezifischen Antiseren getestet. Sie wurden weiterhin bezüglich ihrer rezeptorspezifischen HA, ihres HA-Musters, dem Vorkommen der 0-Serogruppen 01, 02, 04, 06, 07, 08, 018, 025, 075 ("common 0-serogroups"), die bei Harnwegsisolaten vorherrschen, und der Hämolysinbildung charakterisiert. 68 (73 %) der UTl-Stämme und 50 (52%) der fäkalen lsolate zeigten P-Rezeptorspezifität; 16 ( 17%) uropathogene Stämme und 33 (34%) Stämme aus Stuhlproben prägten S, M oder X-Fimbrienantigene aus. 24% der P-hämagglutinierenden (P+) Stämme reagierten mit P (F8)-spezifischem Antiserum. lm Gegensatz dazu reagierten mehr als drei Viertel der s+ -Stämme mit dem S-spezifischen Antiserum. Das HA-Muster Vl und 018- Antigen wurden meistenteils bei p+ -Stämmen gefunden; die HA-Muster V und Vll und die 0-Antigene 02 (M-Typ), 06 und 018 (S-Typ) wurden vorzugsweise bei p--Stämmen nachgewiesen. Ein hoher Prozentsatz von P-fimbrierten Stämmen zeigte Mannose-sensitive Hämagglutination und Hämolysinbildung. KW - Escherichia coli Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72992 ER - TY - JOUR A1 - Hacker, Jörg A1 - Ott, M. A1 - Schmidt, G. A1 - Hull, R. A1 - Goebel, W. T1 - Molecular cloning of the F8 fimbrial antigen from Escherichia coli N2 - The genetic determinant coding for the Pspecific F8 fimbriae was cloned from · the chromosome of the Escherichia coli wild-type strain 2980 (018: K5: H5: FlC, F8). The F8 determinant was further subcloned into the Pstl site of pBR322 and a restriction map was established. In a Southern hybridization experiment identity between the chromosomally encoded F8 determinant of 2980 and its cloned Counterpart was demonstrated. The cloned F8 fimbriäe and those of the wild type strain consist of a protein subunit of nearly 20 kDa. F8 fimbriated strains were agglutinated by an F8 polyclonal antiserum, caused mannose-resistant hemagglutination and attached to human uroepi thellal cells. The cloned F8 determinant was weil expressed in a variety of host strains. KW - Infektionsbiologie KW - Escherichia coli KW - antigen KW - F8 fimbriae KW - gene cloning Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59391 ER - TY - JOUR A1 - Hacker, Jörg A1 - Hof, H. A1 - Hughes, C. A1 - Goebel, W. T1 - Salmonella typhimurium strains carrying hemolysin plasmids and cloned hemolysin. genes from Escherichia coli N2 - Like all other Salmonella typhimurium strains examined, the smooth variants SF1397 (L T2) and 1366 and also their semi-rough and rough derivatives are non-haemolytic. Nevertheless, two haemolysin (Hly) plasmids of E. coli belonging to the inc groups incFllI,lv (pSU316) and incIz (pHly152) were able to be introduced into these strains by conjugation and stably maintained. A considerable percentage of the Hly+ transconjugants obtained had lost parts of their O-side chains, a result of selection for the better recipient capability of « semi-rough» variants rather than the direct influence of the Hly+ plasmids themselves. In contrast to the incF1lI1V plasmid pSU316, which exhibited higher conjugation rates with rough recipients, the incIz plasmid pHly152 was accepted best by smooth strains. Transformation with cloned E. coli haemolysin (hly) determinant was inefficient ( <10-8) for smooth strains, but 102-103 times higher for rough recipients, and was increased by the use of Salmonella-modified DNA. The transform ants and transconjugants were relatively stable and showed the same haemolytic activity as the E. coli donor strains. The virulence of the Hly+ smooth, semi-rough and rough S. typhimurium strains was tested in two mouse models, and neither the mortality rate nor the ability to multiply within the mouse spleen was influenced by the hly determinants. KW - Salmonella typhimurium KW - Plasmid KW - Haemolysin KW - Escherichia coli KW - Virulence Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40309 ER -