The fine structure of the yeast cell wall during protoplast formation was studied by means of phase-contrast microscopy and the freeze-etching technique. The freeze-etching results indicated that at least in some cases the entire wall substance was not removed from the surface of the protoplasts. After a treatment of 30 min to 3 hr with 2% snail enzymes, an innermost thin wall layer as well as ...

Cultures of a stable L-phase variant of Streptococcus faecium F24 produced and retained peptidoglycan precursors intracellularly over the entire growth cycle in a chemically defined medium. The identity of the most abundant precursor, UDP N-acetylmuramyl-L-alanyl-D-glutamyl-L-lysyl-D-alanyl-D-alanine (UDP-MurNAc-pentapeptide), was confirmed by demonstrating in vitro the presence of enzymes requ...

The existence of beta-lectins on protoplast surfaces is confirmed by the agglutination of protoplasts by those Yariv antigens that have sugar specificities which also interact with isolated beta-lectins. Agglutination by beta-maltosyl but not by beta-D-mannosyl Yariv antigens is used to identify some of the structural features required of the ligand for beta-lectin binding. Inhibition of agglut...

The dielectric spectroscopy of Anabaena 7120 protoplast suspensions has been investigated over the frequency range of 40 Hz-110 MHz. The protoplast suspensions showed a complicated dielectric dispersion consisting of at least four distinct sub-dispersions with the increasing frequencies due to the Maxwell-Wagner interfacial polarization. The double-shell model, in which an equivalent shell of t...

Objective: To study the intergenus protoplast fusion bioactive marine Streptomyces sp ANS4 with the Escherichia coli for the strain improvement. Methods: Protoplast of both the organisms was prepared by lysozyme treatment and fused using polyethylene glycol (PEG). Fusant colonies were regenerated using regeneration medium where all the regenerated colonies are powdery in consistency. Microscopi...

The possibility of using ATP content per protoplast as an indicator of freshness was studied in spinach (Spinacia oleracea). The ATP content per protoplast of spinach was determined and compared during 3 days of storage at 25 °C. ATP content increased rapidly at the early stages of storage, reaching a peak level after 24 h. After one day (24 h) of storage, the ATP content decreased with the sto...

Palmitic, stearic, oleic, and linoleic acids at concentrations of 200 nmol/ml all inhibited autolysin activity 80% or more in whole cells or cell-free extracts. This concentration of the saturated fatty acids palmitic acid and stearic acid had little or no effect on the growth of whole cells or protoplasts. However, the unsaturated fatty acids oleic acid and linoleic acid induced lysis in both ...

Previous studies (Storck and Wachsman, 1957; Weibull, Beckman, and Bergstrom, 1959; Wachsman, Fukuhara, and Nisman, 1960) on enzyme localization were performed with cell fractions, obtained by lysing protoplasts in media of low osmotic pressure. In an attempt to determine the effect of the tonicity of the lysing medium on the distribution of enzyme activities between the membrane containing and...