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Biomedical subjects

G B Cox

Publications and source records attributed to G B Cox.

136 records · Page 8Linked to original sources
PubMed1969

Biosynthesis of ubiquinone in Escherichia coli K-12: location of genes affecting the metabolism of 3-octaprenyl-4-hydroxybenzoic acid and 2-octaprenylphenol.

Two genes (ubiB and ubiD) concerned with two successive reactions in ubiquinone biosynthesis in Escherichia coli were mapped and found to be closely linked. Mutant strains of E. coli carrying the ubiB(-) and ubiD(-) alleles were shown to accumulate 2-octaprenylphenol and 3-octaprenyl-4-hydroxybenzoic acid, respectively. These compounds were isolated and identified by using nuclear magnetic resonance and mass and infrared spectroscopy. Cell extracts from the mutant strain carrying the ubiD(-) allele lack 3-octaprenyl-4-hydroxybenzoate decarboxylase activity.

Benzoates↗
PubMed1968

Mutant strains of Escherichia coli K-12 unable to form ubiquinone.

A strain of Escherichia coli was isolated which was unable to form ubiquinone. This mutant was obtained by selecting strains unable to grow on malate as sole source of carbon. Such strains were further screened by examination of the quinone content of cells grown on a glucose medium. A mutant unable to form vitamin K was also isolated by this procedure. A genetic analysis of the ubiquinoneless strain showed that it possessed two mutations affecting ubiquinone biosynthesis.

Chromatography↗
PubMed1966

The role of shikimic acid in the biosynthesis of vitamin K2.

1. Shikimic acid was shown to be a precursor of vitamin K(2) (MK-8) in Escherichia coli. 2. The benzene ring of the naphthaquinone arises from shikimic acid. 3. The methyl group of methionine is incorporated into vitamin K(2). 4. A scheme relating the biosynthesis of vitamin K(2) and ubiquinone to the general pathway of aromatic biosynthesis is proposed.

Acetates↗