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M J Pelczar

Publications and source records attributed to M J Pelczar.

11 recordsLinked to original sources

Analysis of deoxyribonucleic acid of Neisseria caviae and other Neisseria.

LaMacchia, Elizabeth H. (University of Maryland, College Park), and Michael J. Pelczar, Jr. Analyses of deoxyribonucleic acid of Neisseria caviae and other Neisseria. J. Bacteriol. 91:514-516. 1966.-The base composition of deoxyribonucleate preparations extracted from 11 strains of Neisseria caviae, expressed in terms of mole per cent guanine plus cytosine ranged from 47.7 to 50.4, with an average of 49.2. This compared closely with the values obtained for DNA from two strains of N. perflava, which were 49.2 and 50.5%, as well as with published values for most other Neisseria species. The values obtained for five strains of N. catarrhalis, however, ranged from 42.3 to 45.7%. These results suggest that N. caviae may be more closely related to Neisseria spp. other than N. catarrhalis.

Chromatography, Paper↗

Free Amino Acids in Serine-Antagonized Cells of Tetrahymena pyriformis.

Wragg, June B. (Agricultural Research Service, Beltsville, Md.), Howard Reynolds, and Michael J. Pelczar, Jr. Free amino acids in serine-antagonized cells of Tetrahymena pyriformis. J. Bacteriol. 90:748-754. 1965.-Growth inhibition of Tetrahymena pyriformis by l-serine in a chemically defined medium was reversed by l-arginine in a manner which resembled competitive antagonism. Composition of the free amino acid pools from cells grown in either a balanced amino acid mixture or a mixture with serine concentrations which inhibited growth suggested an antagonism by serine with energy-yielding reactions. Growth in media with excess serine resulted in the accumulation of higher concentrations of free cellular amino acids and an apparent increase in the rate of conversion of arginine to ornithine, as compared with growth in the balanced medium. The results suggested that serine or a metabolic product of serine interferes with the formation of pyruvic acid. In the presence of high levels of serine, arginine appeared to be metabolized more rapidly and to be spared when alanine, aspartic acid, or glutamic acid was added to the unbalanced medium.

Journal Article↗