ISSN:
1572-9699
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The effect of various factors such as sodium chloride, sodium citrate, pH, buffers, and enzymatic and physical disruption of cells on the release of penicillinase by Staphylococcus aureus ATCC 14458 was investigated. Penicillinase was measured at selected time intervals from supernates of cultures grown in Antibiotic Medium 3 broth containing various concentrations of salts or buffers or from supernates of cultures treated with lysostaphin and subsequently disrupted by French press treatment. Incubation of cells with media containing either sodium chloride (5, 10, and 15%), sodium citrate (5 and 10%), or organic buffers (Tris-HC1, 2.5, 5.0, and 7.5%; BES, 10 and 20%) resulted in a significant stimulation of the release of penicillinase when compared to control cells. It was also observed that pH 7.0–7.5 was optimal for penicillinase activity and release. From studies of enzymatic and mechanical disruption of cells, it was observed that an increase in ionic strength of the suspending medium to certain optimal levels appeared to stimulate the conversion of penicillinase to an extracellular form. Electron microscopic studies revealed that a large number of mesosomal vesicles seemed to be present in cells incubated for 4 hours in media containing various concentrations of sodium chloride. It is proposed that either appearance of vesicles or convolution of cell membrane, which may be caused by further synthesis of new membrane, is involved in stimulation of the synthesis and release of membrane-bound penicillinase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00403658
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