ISSN:
1432-072X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 1. Treatment of Streptomyces albus G with lysozyme (mg dry weight mycelium/mg lysozyme = 2–3/1) leads to the isolation of membrane fractions whose yields amount to 12–20% of the total celullar protein depending upon the age and state of the bacterial culture. 2. The isolated fractions are composed of 52.7 per cent protein and 41 per cent lipid with minor amounts of hexose (2.3–2.4%), hexosamines (1.6–2.1%), RNA (2%) and DNA (0.45%). They possess a chemical composition similar to that of other membrane systems. 3. NADH oxidase activities are associated with the membrane fractions from cells of 18–20 h of age. These activities are not detected in the membrane fractions from older cells. 4. All membrane fractions shape small vesicles. Differences in size and shape are, however, found between membrane preparations from cells of distinct ages. 5. dd-carboxypeptidase is not selectively localized in a membrane fraction of a certain age. The subcellular distribution of this activity is similar to that of other lytic endopeptidases of S. albus G. 6. The amounts of dd-carboxypeptidase associated with the various membrane fractions are variable and never very high. The specificity of the dd-carboxypeptidase activity associated with membrane fractions differs from that of the soluble enzyme. 7. These results are discussed in relationship with the carboxypeptidase-transpeptidase hypothesis (Leyh-Bouille et al., 1970).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00412246
