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Biomedical subjects

B J Abbott

Publications and source records attributed to B J Abbott.

At least 55 records · Page 3Linked to original sources
PubMed1973

Growth of Acinetobacter calcoaceticus on ethanol.

A soil microorganism, identified as Acinetobacter calcoaceticus, was cultivated on ethanol as a sole source of carbon. This organism grew with a maximum specific growth rate of 0.7/h. The pH optimum for growth was between 6.5 and 7.5, and the temperature optimum was between 32 and 35 C. Ethanol metabolism by this organism was inducible by ethanol, and the presence of acetate led to the repression of ethanol dehydrogenase. At higher cell densities the cessation of growth on ethanol was accompanied by the accumulation of acetate or acetaldehyde, or both. These accumulations were attributed to a reduction in the magnesium or sulfur content of the medium and a lack of feedback inhibition by acetate of alcohol dehydrogenase.

Acetates↗
PubMed1973

Oxidation of 1-alkenes to 1,2-epoxyalkanes by Pseudomonas oleovorans.

Resting cells of Pseudomonas oleovorans PO-1R that had been grown on octane oxidized 1-alkenes containing 6 to 12 carbon atoms and 1,7-octadiene to their corresponding 1,2-epoxides. The microorganism was capable of growing on 1-octene but not on 1,7-octadiene as a sole carbon source. The optimal temperature, pH, and 1-octene concentration for 1,2-epoxyoctane production by the resting cells were 34 to 40 C, pH 7 to 8, and 1.5 mg of 1-octene per ml, respectively. Epoxide concentration reached a maximum after 150 min of incubation and subsequently declined. In the absence of 1-octene, the epoxide was metabolized readily by the resting cells. The amount of 1,2-epoxyoctane produced was dependent on the initial cell concentration. With larger cell populations, the amount of epoxide present after 60 min of incubation was less than the amount observed at lower population densities after the same time period. This relationship was attributed to the rapid depletion of 1-octene at high biomass concentrations and the resultant early initiation of epoxide degradation by the resting cells.

Alkanes↗
PubMed1968

Oxidation of alkanes to internal monoalkenes by a Nocardia.

A suspension of glucose-grown resting cells of Nocardia salmonicolor PSU-N-18 oxidized hexadecane to a mixture of internal monohexadecenes. The latter exhibited a cis configuration, and the mixture consisted of the following: 7-hexadecene, 80%; 8-hexadecene, 18%; and 6-hexadecene, 2%. Alkanes other than hexadecane also were unsaturated by the resting cells, and the composition of the monoalkenes resulting from octadecane dehydrogenation was 9-octadecene, 91%; 8-octadecene, 2 to 3%; 7-octadecene, 1 to 2%; and 6- and 5-octadecenes, trace amounts. Only minute quantities of unsaturated hydrocarbons accumulated during growth on hexadecane and during resting-cell incubation of hexadecane-grown cells with hexadecane. The dehydrogenation of hydrocarbons did not appear to be related to the formation of unsaturated fatty acids. It is postulated that double bond insertion may represent an early step in a new pathway of aliphatic hydrocarbon degradation.

Alkanes↗