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J B DAVIS

Publications and source records attributed to J B DAVIS.

At least 19 recordsLinked to original sources
PubMed1964

MICROBIAL INCORPORATION OF FATTY ACIDS DERIVED FROM N-ALKANES INTO GLYCERIDES AND WAXES.

When n-alkanes with 13 to 20 carbon atoms were fed to a Nocardia closely related to N. salmonicolor, the produced cellular triglycerides and aliphatic waxes invariably contained fatty acids with an even or an odd number of carbon atoms subject to this feature of the n-alkane substrate. Beta-oxidation and C(2) addition are both operative, as evidenced by the spectra of fatty acids incorporated into the cellular lipid components. There is no distinction in the rate of microbial incorporation of the odd-or even-numbered carbon chains. The fatty acids are apparently directly derived from the long chain n-alkanes, rather than synthesized via the classic C(2)-condensation route. The alcohol component of waxes produced by the Nocardia is invariably of the same chain length as the n-alkane substrate.

Alcohols↗
PubMed1964

CELLULAR LIPIDS OF A NOCARDIA GROWN ON PROPANE AND N-BUTANE.

Lipid fractions of propane- and n-butane-grown nocardial cells each contain a chloroform-soluble, ether-insoluble polymer not observed previously in liquid n-alkane-grown cells. The polymer in propane-grown cells is poly-beta-hydroxybutyrate. The polymer in n-butane-grown cells apparently contains unsaturation in the molecule, and is identified tentatively as a co-polymer of beta-hydroxybutyric and beta-hydroxybutenoic (specifically 3-hydroxy 2-butenoic) acids. The other major component of the lipid fraction consists of triglycerides containing principally palmitic and stearic acids. There seems to be little qualitative distinction in the glycerides of propane- or n-butane-grown cells. Oxidative assimilation of n-butane is described.

Butanes↗
PubMed1964

ATMOSPHERIC NITROGEN FIXATION BY METHANE-OXIDIZING BACTERIA.

Davis, J. B. (Socony Mobil Oil Co., Inc., Dallas, Tex.), V. F. Coty, and J. P. Stanley. Atmospheric nitrogen fixation by methane-oxidizing bacteria. J. Bacteriol. 88:468-472. 1964.-Methane-oxidizing bacteria capable of fixing atmospheric nitrogen were isolated from garden soil, pond mud, oil field soil, and soil exposed to natural gas, indicating a rather wide prevalence in nature. This may explain the high concentration of organic nitrogen commonly found in soils exposed to gas leakage from pipelines or natural-gas seeps. Added molybdenum was a requirement for growth in a nitrogen-free mineral salts medium. All nitrogen-fixing, methane-oxidizing bacteria isolated were gram-negative, nonsporeforming, usually motile rods. Colonies were light yellow, yellow, or white. The most common isolate, which formed light-yellow colonies, is referred to as Pseudomonas methanitrificans sp. n., and is distinguished from Pseudomonas (Methanomonas) methanica by nitrogen-fixing ability and a preponderance of poly-beta-hydroxybutyrate in the cellular lipid fraction.

Bacteria↗
PubMed1961

Oxidation of alkyl-substituted cyclic hydrocarbons by a Nocardia during growth on n-alkanes.

Nocardia 107-332, a soil isolate, oxidizes short-chain alkyl-substituted cyclic hydrocarbons to cyclic acids while growing on n-alkanes. Cyclic acids are produced also from relatively long-chain alkyl-substituted cyclics such as n-nonylbenzene or n-dodecylbenzene which alone support growth in a mineral-salts medium. omega-Oxidation of the alkyl substituents is followed by beta-oxidation. It is of particular interest that cyclic acids such as cyclohexaneacetic and phenylacetic with C(2) residual carboxylic acid substituents are resistant to further oxidation by the nocardia but cyclic acids with C(1) or C(3) substituents are readily oxidized and utilized for growth. The specificity of microbial oxidations is demonstrated by the conversion of p-isopropyltoluene (p-cymene) to p-isopropylbenzoic acid in n-alkane, growth-supported nocardia cultures.

Alkanes↗
PubMed1958

Open fractures.

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Fractures, Bone↗