Serum response of Escherichia coli strains causing dyspepsia and urinary tract infection: relation to alpha-hemolysin production and O type.

A total of 109 alpha-hemolytic and 104 nonhemolytic Escherichia coli isolates from children with dyspepsia and urinary tract infections were investigated for resistance to the bactericidal activity of human serum. A significantly higher proportion of serum resistance was found in alpha-hemolytic E. coli isolates than in nonhemolytic isolates (P < 0.

[New findings on alpha-hemolytic strains of E. coli in urinary tract infections. I. alpha-hemolysin and adhesins].

Alphahaemolysin (AH) is one of the important factors of virulence of E. coli strains in urinary infections. The synthesis and secretion of AH is coded by four HLA genes which in the majority of strains are located on the chromosome.

[Alpha-hemolytic strains of Escherichia coli isolated in urinary tract infections in small children].

The authors focused attention on testing of biological properties of alpha-haemolytic strains of E. coli in infections of the urinary pathways in children and on the antibody response against alpha-haemolysin. The strains belonged into serogroups 02, 04, 06, 018, 075, 0112.

Partial purification of alpha-hemolysin in Escherichia coli.

The present paper describes isolation and purification of alpha-hemolysin of Escherichia coli. The optimum production medium was found to be the Todd-Hewitt broth. Out of thirteen fractions obtained after separation on Sephadex G-200, two fractions possessed the highest relative specific activity.

[Escherichia coli in diarrheal disease in young children].

The authors describe a lower incidence of enteropathogenetic serogroups of Escherichia coli (EPEC) in 1981-1987. Of 85 EPEC strains tested for the presence of factors of virulence (fimbrim, enterotoxins, haemolysins, colicins) and factors of virulence against six antimicrobial substances (tetracycline, streptomycin, chloramphenicol, kanamycin, ampicillin, sulfamethoxidine) only three strains did not possess any of the mentioned factors. The authors draw attention to other pathogenetically important groups of E.