Purified disaccharide peptide monomers obtained from Neisseria gonorrhoeae by enzymatic digestion of gonococcal peptidoglycan damaged the mucosa of human fallopian tubes in organ culture. Two peptidoglycan fragments were tested: a nonreducing, anhydromuramyl-containing monomer (the principal fragment shed by growing gonococci) and the analogous reducing, muramidase-derived monomer. The damage produced by either of these peptidoglycan monomers resulted in sloughing of ciliated cells from the mucosa and resembled the damage observed in active gonococcal infection and that produced by filter-sterilized toxic supernatant fluids from gonococcal-infected organ cultures. The minimal toxic dose of peptidoglycan monomers was 0.75 micrograms/ml. Neither lipopolysaccharide, sodium dodecyl sulfate, nor Triton X-100, possible contaminants from the monomer-purification procedures, was present in sufficient quantity to account for the damage. Both of the gonococcal peptidoglycan monomers may be present in vivo and thus may play a role in the pathogenesis of gonococcal infection.

No abstract

Peptidoglycan (PG) turnover in exponentially growing Neisseria gonorrhoeae RD5 type 4 was accompanied by release of soluble PG fragments into the medium. Turnover of the D-[14C]glucosamine-labeled glycan moiety and of the meso

Peptidoglycan from Neisseria gonorrhoeae RD5 was completely degraded by hen egg white lysozyme and was not extensively O-acetylated. In contrast, peptidoglycans from gonococcal strains FA19 and FA102 (a penicillin-resistant mutant derived from FA19), were markedly resistant to digestion by hen egg white lysozyme and were extensively O-acetylated.

Bordetella pertussis is known to release a factor which promotes the loss of ciliated respiratory epithelium and copurifies with a soluble peptidoglycan (PG) fragment termed tracheal cytotoxin (TCT). The objective of this study was to determine whether pertussis organisms turn over and release PG derivatives in addition to TCT. B. pertussis Tohama (phase III) was grown in liquid Stainer-Scholte medium containing [3H]diaminopimelic acid (DAP) to label PG specifically, washed to remove free label, and suspended in fresh medium without [3H]DAP. Molecular sieve chromatography of supernatants obtained from such cultures revealed a single included peak of 3H, the elution volume of which corresponded roughly to a disaccharide peptide monomer standard (ca. 103 daltons). This material (i) contained [3H]DAP in acid-hydrolyzable linkage, (ii) comigrated with 1,6-anhydro-N-acetylmuramic acid-containing disaccharide peptides on paper chromatography, (iii) was resistant to degradation by mild alkali, and (iv) was indistinguishable from authentic-TCT by high-voltage paper electrophoresis and two reversed-phase high-performance liquid chromatography systems. Together, the data suggest that B. pertussis releases a markedly homogeneous set of PG fragments, consisting principally of TCT, and that TCT is possibly a nonreducing, anhydromuramic acid-containing fragment or a cyclic PG derivative.