phenylmercuric-acetate and 4-hydroxymercuribenzoate

Susceptibility to inorganic mercuric ions and to organomercurials of 237 Pseudomonas aeruginosa clinical strains isolated in Mexico was determined by agar dilution tests. Resistant strains fell into two classes: i) narrow-spectrum resistant strains (27% of total isolates) resistant only to mercuric ions and to merbromin, and most grouped in pyocin type 1; and ii) broad-spectrum resistant strains (5%) with additional resistances to thimerosal, phenylmercury, methylmercury and p-hydroxymercuribenzoate, that belonged mostly to pyocin type 10. Mercurial resistant isolates showed a higher proportion of resistance to antibiotics and metals than did mercurial sensitive isolates, and broad-spectrum resistant strains had the highest frequency of resistance to antibiotics and to tellurite and arsenate.

Topics: Humans; Hydroxymercuribenzoates; Merbromin; Mercuric Chloride; Mercury; Methylmercury Compounds; Phenylmercuric Acetate; Pseudomonas aeruginosa; Thimerosal

Pure human skin fibroblast procollagenase has been utilized in this study as a model system in which to examine the pathways of organomercurial and trypsin activation. Three organomercurials, p-(hydroxymercuri) benzoate, mersalyl, and p-aminophenylmercuric acetate, were able to fully activate human skin procollagenase with no accompanying loss of molecular weight. Lower molecular weight species were subsequently produced, particularly with a fourth organomercurial, phenylmercuric chloride. The activation process was dependent upon the concentration of the organomercurial compound and the time of incubation, but not on enzyme protein concentration. No evidence of a role for free sulfhydryls was found. Trypsin produced an initial cleavage product of procollagenase which was collagenolytically inactive yet underwent a concentration independent autocatalysis. Thus, procollagenase appeared to have an autocatalytic property which was enhanced by treatment with a variety of agents, all of which may function by perturbation of the zymogen conformation.

Topics: Cell Line; Collagenases; Enzyme Activation; Enzyme Precursors; Fibroblasts; Humans; Hydroxymercuribenzoates; Mersalyl; Microbial Collagenase; Molecular Weight; Organomercury Compounds; Phenylmercuric Acetate; Skin; Trypsin