Effects of human neutrophil granule extracts on macromolecular synthesis in Neisseria gonorrhoeae

Abstract

Neisseria gonorrhoeae were exponentially killed for 120 min (i.e., they were prevented from forming colonies on agar) by extracts of human neutrophil granules; however, macromolecular synthesis, indicated by incorporation of radiolabeled precursors in trichloroacetic acid-precipitable material, continued at or above zero time control values for 45 min. Protein, deoxyribonucleic acid, and ribonucleic acid synthesis appeared to decrease simultaneously after 45 min. Little or no lysis of gonococci occurred during the first 60 min of incubation. The ions K+, Na+, Ca2+, Cll-, S042and PO43at concentrations of l100 mM did not affect granule extract bactericidal activity. On the other hand, 20 mM Mg2+ completely inhibited killing when initially present along with granule extract or when added within 2 to 5 min after granule extract was added to a suspension of gonococci. Gonococci treated with granule extract, washed, and then incubated in the absence of extract died as if extract were still present. The ability of subinhibitory concentrations of actinomycin D or erythromycin to inhibit growth and protein and nucleic acid synthesis was synergistically increased in the presence of granule extract. The above information suggests that a bactericidal component(s) of human neutrophil granules sticks to gonococci, altering their outer membrane permeability and their ability to divide. MATERIALS AND METHODS Bacteria. N. gonorrhoeae strain F62 was obtained

Molecular mechanism for the antigonococcal action of lysosomal cathepsin G

“…Ultimately, this would lead to bacterial death if the lesion remained unrepaired. Consistent with the work of Rest and co-workers (Rest, 1979;Buck and Rest, 1981;Rock and Rest, 1988) and our own studies (Casey et al, 1985;Shafer et ai, 1986a,b) (Shafer et at., 1982). Gonococcal susceptibility to purified lysosomal cat G, prepared from human PMNL granules and treated with di-isopropylfluorophosphate (Shafer et al.…”

Antimicrobial mechanisms against Acinetobacter calcoaceticus of rat polymorphonuclear leukocyte granule extract

“…The nonoxidative antimicrobial potential of crude, unfractionated extract from PMN granules (2,3,7,11) and isolated cationic granule proteins (4,9,11,(14)(15)(16)(17)(18)(19) has been extensively studied. Although cationic proteins are considered to be largely responsible for the nonoxidative antimicrobial activity of granule contents, the question of whether their activity accurately represents the total nonoxidative antimicrobial potential of PMN granule contents has been raised (2, 7).…”

“…Although cationic proteins are considered to be largely responsible for the nonoxidative antimicrobial activity of granule contents, the question of whether their activity accurately represents the total nonoxidative antimicrobial potential of PMN granule contents has been raised (2, 7). Buck and Rest (2) showed that crude granule extract from human PMNs reduced the viability of N. gonorrhoeae without affecting macromolecular synthesis. Other investigators isolated cationic proteins from human PMN granules, Odeberg and Olsson (14) demonstrating that a fraction which contained several 25,000-molecular-weight proteins inhibited macromolecular synthesis by Staphylococcus aureus and E. coli and Weiss et al (18) showing that a protein with a molecular weight of 58,000 to 60,000 had little effect on macromolecular synthesis by several gram-positive and gram-negative bacteria.…”

“…Likely responsible for the majority of this antimicrobial activity are cationic proteinshighly positively charged proteins ranging widely in molecular weight and possessing potent nonenzymatic antimicrobial activity (4,9,11,(14)(15)(16)(17)(18)(19). A number of studies have characterized the mechanisms of nonoxidative antimicrobial action of contents isolated from human (2,14,18) and rabbit (3,17,19) PMN granules against gram-negative bacteria. Buck and Rest (2) showed that unfractionated granule extract from human PMNs reduced the viability of Neisseria gonorrhoeae without affecting macromolecular synthesis.…”

“…A number of studies have characterized the mechanisms of nonoxidative antimicrobial action of contents isolated from human (2,14,18) and rabbit (3,17,19) PMN granules against gram-negative bacteria. Buck and Rest (2) showed that unfractionated granule extract from human PMNs reduced the viability of Neisseria gonorrhoeae without affecting macromolecular synthesis. Odeberg and Olsson (14), working with purified cationic proteins from human PMN granules, showed these granule components to inhibit both macromolecular synthesis and viability of Escherichia coli.…”