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Biomedical subjects

J W FOSTER

Publications and source records attributed to J W FOSTER.

At least 19 recordsLinked to original sources
PubMed1963

DITERMINAL OXIDATION OF LONG-CHAIN ALKANES BY BACTERIA.

Kester, A. S. (The University of Texas, Austin) and J. W. Foster. Diterminal oxidation of long-chain alkanes by bacteria. J. Bacteriol. 85:859-869. 1963.-A corynebacterial organism capable of growing in mineral salts with individual pure alkanes as carbon sources produces a series of acids from the C(10)-C(14) alkanes. They have been isolated in pure form and identified as monoic, omega-hydroxy monoic, and dioic acids containing the same number of carbon atoms as the substrate alkane. Oxidation took place at both terminal methyl groups-"diterminal oxidation." Appropriate labeling experiments indicate that omega oxidation of fatty acids occurs in this organism and that an oxygenation with O(2) occurs.

Alkanes↗
PubMed1963

METHYL KETONE METABOLISM IN HYDROCARBON-UTILIZING MYCOBACTERIA.

Lukins, H. B. (University of Texas, Austin) and J. W. Foster. Methyl ketone metabolism in hydrocarbon-utilizing mycobacteria. J. Bacteriol. 85: 1074-1087. 1963.-Species of Mycobacterium especially M. smegmatis 422, produced the homologous methyl ketones during the oxidation of propane, n-butane, n-pentane, or n-hexane. A carrier-trapping experiment demonstrated the formation of 2-undecanone, as well as 1,11-undecanedioic acid, during the oxidation of undecane-1-C(14). Aliphatic alkane-utilizing mycobacteria were able to grow at the expense of several aliphatic methyl ketones as sole sources of carbon. Other ketones which did not support growth were oxidized by resting bacterial suspensions. M. smegmatis 422 cells grown on propane or acetone were simultaneously adapted to oxidize both substrates, as well as n-propanol. n-Propanol cells were unadapted to propane or acetone. Acetone produced from propane in a medium enriched in D(2)O contained a negligible quantity of D, presumably eliminating propylene as an intermediate in the oxidation. Cells grown at the expense of alkanes or methyl ketones in the presence of O(2) (18) had a higher content of O(18) than did cells grown on terminally oxidized compounds, e.g., primary alcohols or fatty acids. An oxygenase reaction is postulated for the attack on methyl ketones. Acetol was isolated and characterized as an oxidation product of acetone by M. smegmatis 422. Acetol-grown cells had a higher O(18) content than did n-propanol cells, and its utilization appears to involve at least one oxygenase reaction. Acetol produced from acetone in the presence of O(2) (18) was not enriched in the isotope, indicating the occurrence of exchange reactions or of oxygenation reactions at a later stage in the assimilation of acetone and acetol.

1-Propanol↗
PubMed1962

Electron microscopy of spores of Bacillus megaterium with special reference to the effects of fixation and thin sectioning.

Resting spores of Bacillus megaterium appear uniformly opaque and undifferentiated under the electron microscope. Germinated spores and spores which have lost their dipicolinic acid underwent characteristic changes in structure. Spores fixed with KMnO(4) lose their dipicolinic acid. Spores fixed with OsO(4) under certain conditions retain their dipicolinic acid. When conventional sectioning procedures are used with either method of fixation, abnormal spore structure is produced as a result of the solution of cellular constitutents. Dry sections of unfixed spores embedded in methacrylate reveal the spore structure in a more normal state. Indirect evidence has been obtained for the existence of a penetration barrier at or near the outer edge of the cortex.

Bacillus megaterium↗
PubMed1962

Rupture of bacteria by explosive decompression.

Foster, John W. (University of Georgia, Athens), Robert M. Cowan, and Ted A. Maag. Rupture of bacteria by explosive decompression. J. Bacteriol. 83:330-334. 1962.-A device is described for instantaneously rupturing bacteria and other cells in a closed system under controlled conditions by explosive decompression. With this device, 31 to 59% of Serratia marcescens, ranging up to 20 mg (dry wt) of cells per ml, were ruptured after nitrogen saturation at 1740 psi. Under similar conditions, 10 to 25% of Brucella abortus and Staphylococcus aureus were ruptured. Rupture of these organisms produced readily separable cell walls. Centrifugation in linear glycerol gradients was applied to further separate cell walls from debris. Mycoplasma gallinarum, Leptospira pomona, and Eimeria tenella (avian coccidia) oöcysts were also broken up by the decompression chamber. Pressure and duration of saturation of cells with gas affected rupture efficiency. Within the limits of this study, concentration of organisms and volume of suspensions did not have a definite effect.

Bacteria↗
PubMed1962

Immunological role of Brucella abortus cell walls.

Foster, John W. (University of Georgia, Athens) and Edgar Ribi. Immunological role of Brucella abortus cell walls. J. Bacteriol. 84:258-268. 1962-Cell walls and protoplasm were prepared from organisms disrupted in a refrigerated pressure cell. Cell walls were purified by sedimentation in a linear glycerol gradient. Antigens capable of protecting mice against infection with Brucella abortus and of reacting with antiserum prepared against whole cells were present chiefly in the cell wall; substances lethal to mice and responsible for primary inflammation of rabbit skin were also associated with the cell wall. Limited activity of protoplasm in these biological tests may or may not be due to contamination with cell-wall material. A substance extracted from whole cells with aqueous ether possessed an immunizing potency superior to that of killed whole cells or cell walls.

Animals↗