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G R PEARSON

Publications and source records attributed to G R PEARSON.

7 recordsLinked to original sources
PubMed1964

PRODUCTION AND CHARACTERIZATION OF BRUCELLA SPHEROPLASTS.

Hines, William D. (University of Chicago, Chicago, Ill.), Bob A. Freeman, and Gary R. Pearson. Production and characterization of Brucella spheroplasts. J. Bacteriol. 87:438-445. 1964.-Spheroplasts of Brucella were induced by glycine, penicillin, and a combination of the two. These spheroplasts lacked cell-wall endotoxin but did react with antiserum prepared against cell wall and against whole cells. Phase-contrast photomicrographs and electron micrographs are presented, which show no morphological difference between the protoplasts produced by penicillin and by glycine. The glycine and glycine-penicillin spheroplasts were osmotically sensitive, would not reproduce, and only a small percentage reverted to the bacillary form. Penicillin spheroplasts would not reproduce and were not osmotically sensitive. Penicillin spheroplasts showed significant reversion when induced by low concentrations of penicillin, but the rate of reversion decreased with increasing antibiotic concentration. Penicillin and glycine spheroplasts adsorbed brucellaphage at a reduced rate compared with normal Brucella, but spheroplasts produced by the combined action of penicillin and glycine failed to demonstrate brucellaphage adsorption.

Bacteriophages↗
PubMed1964

FINE STRUCTURE OF BRUCELLA SUIS SPHEROPLASTS.

Hines, William D. (University of Chicago, Chicago, Ill.), Bob A. Freeman, and Gary R. Pearson. Fine structure of Brucella suis spheroplasts. J. Bacteriol. 87:1492-1498. 1964.-Spheroplasts of Brucella suis, prepared by treatment with penicillin and glycine, and normal cells were sectioned and studied by electron microscopy. These spheroplasts differed from the normal cell in that they were greatly expanded and coccoid in shape. The cell wall and cytoplasmic membrane were more easily demonstrated in the spheroplasts. The cell wall and cytoplasmic membrane of normal cells appeared structureless, but in the spheroplasts both were shown to consist of two dark layers sandwiching a lighter layer. The cytoplasm of the spheroplasts was more dilute than that of normal cells and, in the case of glycine-induced spheroplasts, tended to aggregate.

Brucella↗