Penicillinase plasmids of Staphylococcus aureus often contain genes conferring resistance to inorganic mercury (Hg(2+)) and the organomercurial phenylmercury acetate. The mechanism of resistance was found to be the enzymatic hydrolysis of the organomercurial phenylmercury to benzene plus inorganic ionic mercury, which was then enzymatically reduced to metallic mercury (Hg(0)). The Hg(0) was rap...

The structural basis for induction of the mercury resistance operon with inorganic mercury and with the organomercurial compound phenylmercuric acetate was addressed by DNA sequencing analysis and by lac fusion transcription experiments regulated by merR in trans from broad-spectrum-resistance plasmid pDU1358 (Hg2+ and phenylmercury responding). The lac fusion results were compared with those f...

Cytochrome oxidase and catalase are not regarded as sulfhydryldependent enzymes (1). The inhibition of the former by organic mercurial compounds (2) has been thought to involve denaturation (3) rather than interaction with sulfhydryl groups, and it has been suggested that the mercurial inhibition of catalase is also non-specific (4). Because the protein molecule contains reactive groups other t...

The metabolism of [U-(14)C]phenylmercury acetate was studied in the rat. After a single subcutaneous dose a small proportion is excreted unchanged in urine, and a larger amount in bile with some resorption from the gut. The greater part of the dose is broken down in the tissues to yield inorganic mercury which is excreted mainly in faeces, and conjugates of phenol and quinol are excreted in uri...

Environmental pollutants and other chemicals may have increasing impact on the immune system of human beings. Disregulation of the immune system by chemicals may be one of the reasons why the frequency of allergies and autoimmune diseases increases. Human hapten-specific memory lymphocytes can be detected in the blood of patients with druginduced immunologic side effects but not in similarly ex...

A 7.9-kilobase (kb) chromosomal fragment was cloned from a mercury-resistant Bacillus sp. In Escherichia coli, in the presence of a second plasmid carrying functional transport genes, resistance to HgCl2 and to phenylmercury acetate (PMA) was expressed. Shortening the cloned fragment to 3.8 kb abolished resistance to PMA but not to HgCl2. In Bacillus subtilis, the 3.8-kb fragment produced mercu...

method previously employed by westoo for the determination of alkylmercury compounds was producing very wide picks during g.c. analyses. changing the column temperature, carrier gas flow and pressure did not supersede the problem. therefore change in packing materials was experienced. 5% dc-200 on gas-chrom did not work. a packing material used for chlorinated hydrocarbons w, 80-100 mesh. as th...