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Biomedical subjects

R Gross

Publications and source records attributed to R Gross.

At least 505 records · Page 28Linked to original sources
PubMed1973

Formation and secretion of induced penicillinase in protoplasts of Staphylococcus aureus.

Conditions suitable for induced formation and secretion of penicillinase (EC 3.5.2.6) in protoplasts of Staphylococcus aureus were determined. No requirement was found for cells to be exposed to inducer prior to formation of protoplasts. Neither cell wall components nor mesosomes appeared to be necessary for induction or secretion. In medium containing 1.1 M sucrose about half of the formed enzyme was soluble, whereas in medium containing 0.37 M sodium succinate only about 10% of the penicillinase remained protoplast-bound. Low concentrations of polyanions (dextran sulfate and potassium polyvinyl-sulfonate) inhibited the formation of induced penicillinase, as did 4-acetamido-4'-isothiocyano-stilbene 2,2'-disulfonic acid. None of these compounds inhibited the activity of native penicillinase, and none would be expected to pass through the protoplast membrane. Penicillinase, denatured in 4 M urea, could be renatured by dilution in the presence of benzylpenicillin, and the above three inhibitors interfered strongly with this process. The results are taken as evidence that penicillinase may be secreted through the protoplast membrane in an incompletely folded form.

Enzyme Induction↗
PubMed1973

Preparation of metabolically active Staphylococcus aureus protoplasts by use of the Aeromonas hydrophila lytic enzyme.

Stable, metabolically active protoplasts of Staphylococcus aureus have been prepared by the use of a staphylolytic enzyme produced by Aeromonas hydrophila. Respiratory and glycolytic rates and synthesis of nucleic acids, protein, and lipid in these protoplasts, stabilized variously in 1.1 M sucrose, 0.37 M sodium succinate, or 0.37 M sodium sulfate, have been shown to be comparable with the same parameters in intact cells under the same conditions.

Acetates↗