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M P STARR

Publications and source records attributed to M P STARR.

At least 19 recordsLinked to original sources
PubMed1964

PIGMENTATION AND TAXONOMY OF THE GENUS XANTHOMONAS.

Starr, Mortimer P. (University of California, Davis), and William L. Stephens. Pigmentation and taxonomy of the genus Xanthomonas. J. Bacteriol. 87:293-302. 1964.-The colonies formed by phytopathogenic bacteria of the genus Xanthomonas are typically yellow in color. This chromogenesis stems from the presence in all yellow xanthomonads of a particular carotenoid pigment. This unique "Xanthomonas-carotenoid," which has not been found in any yellow nonxanthomonad, is characterized herein to the extent required for its recognition by relatively simple screening procedures. In general, the occurrence of a carotenoid "alcohol" with absorption maxima at 418, 437, and 463 mmu (petroleum ether)-in a gram-negative, polarly-flagellated, oxidative, rod-shaped bacterium-would suggest placement of that microorganism in the genus Xanthomonas.

Bacteria↗
PubMed1963

LOCALIZATION OF CAROTENOID PIGMENT IN THE CYTOPLASMIC MEMBRANE OF XANTHOMONAS JUGLANDIS.

Stephens, William L. (University of California, Davis), and Mortimer P. Starr. Localization of carotenoid pigment in the cytoplasmic membrane of Xanthomonas juglandis. J. Bacteriol. 86:1070-1074. 1963.-The kinetics of release of carotenoid pigment from cells of Xanthomonas juglandis, disrupted by sonic or ballistic treatment, showed the pigment to be localized in the cell envelope. Cells subjected to ballistic disintegration released carotenoid at a rate identical to that of a membrane component (reduced nicotinamide adenine dinucleotide oxidase) and at a slightly higher rate than a wall component (hexosamine). Thus, the membrane portion of the cell envelope is the most probable locus of the unique carotenoid pigment of X. juglandis.

Carotenoids↗
PubMed1962

Eliminative split of pectic substances by phytopathogenic soft-rot bacteria.

Culture filtrates of Erwinia carotovora and Bacillus polymyxa split pectic substances to yield a product that absorbs at 230 mmicro, and which reacts with thiobarbituric acid to form a substance that absorbs at 547 mmicro. This product is believed to be a C-4,5-unsaturated oli-gouronide. The preferred substrate is polygalacturonic acid rather than pectin; the enzyme, provisionally named polygalacturonic-trans-eliminase, is activated by calcium.

Bacillus↗