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The membrane lipids of Halobacterium halobium.

ABSTRACT: The lipid content of the cell membrane of Halobacterium halobium increased from about 15% to 21% during exponential growth of the organism. Total lipid phosphorus more than doubled during the growth cycle. The mixture of membrane lipids from stationary-phase organisms was similar to lipid mixtures from whole cells of other halobacteria inasmuch as 80% of the lipid phosphorus occurred in a diether analogue of phosphatidylglycerophosphate and an additional 7.5% occurred in the ether analogue of phosphatidylglycerol. The lipid mixture was more complex than those reported for other halophils, however, 12 components being recognized in the acetone-insoluble fraction and 17 in the acetone-soluble fraction. There were major changes in the proportions of some minor components of the acetone-insoluble fraction during a growth cycle. Three nitrogenous lipids were recognized in the acetone-insoluble fraction, but all were present in relatively low proportion. One, which was not a phospholipid, contained a bound peptide. Of the 17 acetonesoluble compounds, 15 were pigments. The major carotenoids were alpha- and beta-bacteriorubrin. The carotenoid pigments occurred at maximal concentration after 6-7 days' growth.

SUBMITTER: Marshall CL

PROVIDER: S-EPMC1187370 | biostudies-other | 1968 Dec

REPOSITORIES: biostudies-other

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Biological properties of carotenoids extracted from Halobacterium halobium isolated from a Tunisian solar saltern.

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| S-EPMC3853157 | biostudies-literature

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| S-EPMC1162019 | biostudies-other

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| S-EPMC332751 | biostudies-other

Fermentative arginine degradation in Halobacterium salinarium (formerly Halobacterium halobium): genes, gene products, and transcripts of the arcRACB gene cluster.

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| S-EPMC178278 | biostudies-other

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| S-EPMC176715 | biostudies-other

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Project description:This study was conducted to identify the genes involved in the synthesis of membrane-spanning lipids in Thermoanaerobacter ethanolicus JW 200.

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Biosynthesis of membrane-spanning ether lipids in Thermotoga maritima

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