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S J AJL

Publications and source records attributed to S J AJL.

At least 19 recordsLinked to original sources
PubMed1964

THE IDENTIFICATION AND ISOLATION OF TWO MOUSE-TOXIC PROTEIN COMPONENTS IN EXTRACTS FROM PASTEURELLA PESTIS.

The toxin activity of Pasteurella pestis cells, strain "Tjiwidej," was found to be associated with two proteins. Using a disc electrophoresis technique in conjunction with mouse lethality, two toxic proteins were isolated exhibiting intraperitoneal LD(50)'s of less than 1.0 to 1.5 microg protein. Each produced a single characteristic precipitin band on agar gel diffusion plates. The slower migrating toxin in gel diffusion or disc electrophoresis was designated as toxin A. It was shown to be sensitive to deoxycholate and digitonin, did not accumulate in 5-fluorotryptophan treated cells, and was associated with the membrane fraction of the cell. The faster migrating toxin B, apparently is resistant to surface-active agents, and is not affected by treatment of cells with 5-fluorotryptophan. Toxin B is associated with the soluble or cytoplasmic fraction of the cell. This evidence suggested that each toxin represented a distinctly different molecular species. The possibility is discussed that toxin B is synonymous with the murine toxin previously isolated by paper curtain electrophoresis which revealed only one antigen band in the Oudin precipitin reaction.

Animals↗
PubMed1964

SELECTIVE INHIBITION BY TRYPTOPHAN ANALOGUES OF MURINE TOXIN SYNTHESIS IN PASTEURELLA PESTIS.

Montie, Thomas C. (Albert Einstein Medical Center, Philadelphia, Pa.), and Samuel J. Ajl. Selective inhibition by tryptophan analogues of murine toxin synthesis in Pasteurella pestis. J. Bacteriol. 88:1467-1475. 1964.-Washed-cell suspensions of Pasteurella pestis, avirulent strain "Tjiwidej," exhibited a preferential inhibition of toxin synthesis relative to total protein formation, when grown in the presence of various tryptophan analogues. Growth was partially inhibited in the presence of methyl analogues. High concentrations of 5-fluorotryptophan induced slight growth-inhibitory effects. However, toxin production was more sensitive to these levels of the analogue. Growth inhibition appeared not to relate to toxin inhibition. Inhibition of toxin synthesis by analogues was reversed by l-tryptophan and indole. Shikimic acid but not anthranilic acid antagonized the action of 4-methyltryptophan on selective toxin synthesis. The formation of tryptophanless protein accounted for continued protein synthesis in tryptophan-depleted cells. Protein resolved by acrylamide gel electrophoresis from crude cell extracts exhibited two toxic protein bands. The synthesis of one toxin-protein band, the less-mobile of the two, appeared to be associated with the membrane fraction of the cell, and was selectively blocked in cells grown in the presence of tryptophan analogues. Cellular tryptophan levels may determine the quantity and quality of proteins made.

Animals↗
PubMed1963

PLAGUE TOXIN: ITS EFFECT IN VITRO AND IN VIVO.

The murine toxin of Pasteurella pestis inhibited the respiration of heart mitochondria from the rat and the mouse but had little or no effect on the respiration of mitochondria from the rabbit, chimpanzee, dog, and monkey. Alterations occurred in tile S-T segments of the electrocardiogramus recorded corded from rats injected with (1/4) to 10 LD(50) of toxin, but not in those from rats dying of hemorrhagic shock, hypoxia, intoxication with glucose, or Escherichia coli endotoxin. No abnormalities were observed in electrocardiograms from rabbits injected with large amounts of toxin.

Animals↗
PubMed1963

ACTION OF PLAGUE MURINE TOXIN ON MITOCHONDRIA FROM RESISTANT AND SUSCEPTIBLE ANIMALS.

Kadis, Solomon (Albert Einstein Medical Center, Philadelphia, Pa.), Samuel J. Ajl, and James H. Rust, Jr. Action of plague murine toxin on mitochondria from resistant and susceptible animals. J. Bacteriol. 86:757-765. 1963.-Purified murine Pasteurella pestis toxin inhibited the respiration of liver mitochondria isolated from both the rat and the rabbit. Toxin had little or no effect on the respiration of rabbit sarcosomes, but when they were disrupted with either sodium deoxycholate or sonic vibration their respiration was inhibited. The respiration of heart mitochondria from rats immunized with toxoid-adjuvant mixtures was inhibited only slightly by the toxin, whereas the respiration of liver mitochondria from immunized rats was inhibited to the same degree as that from nonimmunized animals. Toxin caused the heart mitochondria of the rat to swell, but had little or no effect on the heart mitochondria of the rabbit. Also, brain mitochondria were not swollen by the toxin.

Animals↗
PubMed1963

BETA-ETHYLMALATE SYNTHETASE.

Rabin, Robert (Albert Einstein Medical Center, Philadelphia, Pa.), Henry C. Reeves, and Samuel J. Ajl. beta-Ethylmalate synthetase. J. Bacteriol. 86:937-944. 1963.-Pseudomonas aeruginosa, when grown in an inorganic salts medium with butyrate as the sole carbon source, produced an enzyme which catalyzed the condensation of butyryl coenzyme A (CoA) and glyoxylate to form beta-ethylmalic acid. Maximal activity was found in the 40 to 60% (NH(4))(2)SO(4) fraction of cell-free extracts. Mg(++) was stimulatory, and the optimal pH was 8.0 to 8.5. beta-Ethylmalic acid-C(14) was demonstrable in paper chromatograms when either glyoxylate-1-C(14) or butyryl CoA-3-C(14) was included in complete systems incubated anaerobically. When either glyoxylate, butyryl CoA, or enzyme was omitted, beta-ethylmalate was not detected. Further evidence that beta-ethylmalic acid-C(14) was the product of the condensation of butyryl CoA-3-C(14) and nonlabeled glyoxylate was provided by synthesis of the derivative 5-ethyluracil-C(14). The derivative was recrystallized to constant specific activity and identified by its melting point and spectral properties.

Acyl Coenzyme A↗