The relation between the bactericidal activity of complement and the character of the bacterial surfaces

Antibody-independent binding of the first component of complement (C1) and its subcomponent C1q to the S and R forms of Salmonella minnesota

“…In general, the S form was found to be more resistant than the Re mutant, which is in agreement with the observations of Rowley (16). Other investigations provided evidence that the composition of the bacterial surface may influence the reaction of the bacteria with complement (18). Therefore, it was of interest to investigate the interaction of S. minnesota wild type and six different core-defective mutants (Ra, Rb, Rc, Rd,, Rd2, and Re) (7).…”

Differential Complement Resistance Mediates Virulence of Haemophilus influenzae Type b

“…However, the relationship between the structure of capsular polysaccharides and their potential for causing human diseases is yet incompletely characterized. Our studies suggest that complement interaction, without the participation of antibody, between these surface structures is an important component of their virulence (39,41).…”

Sensitization of Complement-Resistant Smooth Gram-Negative Bacterial Strains

“…Although many gram-negative bacteria are readilykilled by serum complement in the presence of specific antibody, rough strains are generally much more sensitive than are smooth strains (6,17,25,26,27,31). Indeed, many smooth strains exist which are completely resistant to this bactericidal system when tested in saline (22), saline plus Mg2+ (6,28), phosphate buffer plus Mg2+ (26), and acetate-barbiturate buffer (20). Mg2+ is frequently added to such test systems, since it was shown to activate complement (16,23).…”