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A FRAPPIER

Publications and source records attributed to A FRAPPIER.

At least 19 recordsLinked to original sources
PubMed1964

DIFFERENTIATION BY IMMUNODIFFUSION AND BY QUANTITATIVE IMMUNOFLUORESCENCE BETWEEN 5-FLUOROURACIL-TREATED AND NORMAL CELLS FROM A TOXINOGENIC STAPHYLOCOCCUS AUREUS STRAIN.

De Repentigny, J. (University of Montreal, Montreal, Quebec, Canada), S. Sonea, and A. Frappier. Differentiation by immunodiffusion and by quantitative immunofluorescence between 5-fluorouracil-treated and normal cells from a toxinogenic Staphylococcus aureus strain. J. Bacteriol. 88:444-448. 1964.-Immunodiffusion and quantitative immunofluorescence can both detect antigenic changes produced by 5-fluorouracil (FU) in Staphylococcus aureus Wood 46 strain. When FU is added to the cultures in their logarithmic phase of growth, a number of bacterial antigens are no longer detectable by immuno-diffusion and the intensity of the total immuno-fluorescence of bacteria is diminished; thus, these antigens are either profoundly modified or no longer synthesized. Uracil and, less effectively, thymine can reverse the FU inhibitory effect on the synthesis of antigens, and the number of precipitin lines remains closer to controls. The immunochemical approach provides a new way of obtaining information on the action of this pyrimidine analogue on metabolic processes in pathogenic bacteria. Microscopic quantitative immunofluorescence seems to be adaptable to give indirect information on changes in the metabolism or synthesis or antigens of a single bacterial cell.

Antigens↗
PubMed1962

Changes in immunodiffusion patterns and in nucleic acid content of Staphylococcus aureus grown in the presence of a nucleic acid fluorochrome.

Sonea, S. (University of Montreal, Montreal, Canada), J. de Repentigny, and A. Frappier. Changes in immunodiffusion patterns and in nucleic acid content of Staphylococcus aureus grown in the presence of a nucleic acid fluorochrome. J. Bacteriol. 84:1056-1060. 1962.-When grown in the presence of acridine orange, coagulase-positive Staphylococcus aureus exhibits changes in the number and the shape of its precipitin bands; these are more pronounced with commercial horse staphylococcal antitoxin than with normal human gamma-globulin. Simultaneously, there is an increase in the content of nucleic acids, especially deoxyribonucleic acid. Consequently, when grown in the presence of this nucleic acid fluorochrome, pathogenic staphylococci become similar to nonpathogenic strains in their antigenic structure and nucleic acid content. The bacterial population becomes a mixture of red and green fluorescing cells of different sizes. After centrifugation, most of the large and red fluorescing cells are found in the top layer, which shows more changes in antigenic composition and in nucleic acid content than the bottom layer. In subcultures grown in the absence of acridine orange, the cells revert to the original composition of the pathogenic strains.

Acridines↗