Sources of low-molecular-weight host factors that phenotypically increase the resistance of Haemophilus influenzae type b to bacteriolysis: non-identity with a factor active in gonococci.
Both gonococci and Haemophilus influenzae type b (Hib) in response to incubation with low-molecular-weight components of blood are converted to a relative resistance to killing by antibody and complement in vitro. Recently, cytidine 5'-mono-phospho-N-acetylneuraminic acid (a sialyl donor present in mammalian tissues) was found to convert gonococci. Here we report that this compound was inactive in Hib. In further contrast, the Hib-converting activity of serum was not retained by 500-M, filters, not sensitive to pH 2, and not active in the presence of growth media. Thus the phenotypic resistance in Hib and gonococci appear to have a different metabolic basis. The low-Mr serum factors active in Hib remain to be identified. Filtrates of human nasopharyngeal washes were also active, further suggesting that the converted form resembles the phenotype of Hib in vivo.
Kuratana
M
M
Department of Pediatrics, University of Rochester, New York 14642.
Inzana
T J
TJ
Anderson
P
P
D001770:Blood Bactericidal Activity / Q000187:drug effects; D003569:Cytidine Monophosphate N-Acetylneuraminic Acid / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D006193:Haemophilus influenzae / Q000187:drug effects / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008970:Molecular Weight; D009344:Neisseria gonorrhoeae / Q000187:drug effects / Q000235:genetics / Q000276:immunology*; D010641:Phenotype
D003569:Cytidine Monophosphate N-Acetylneuraminic Acid