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B L Horecker

Publications and source records attributed to B L Horecker.

At least 199 records · Page 11Linked to original sources

Activation of rabbit liver fructose diphosphatase by coenzyme A and acyl carrier protein.

The catalytic activity of rabbit liver fructose diphosphatase is enhanced more than fourfold by treatment with coenzyme A or acyl carrier protein. Other sulfhydryl compounds, such as glutathione or cysteine, are without effect. Activation is reversed by reduced glutathione or cysteine, indicating that the enzyme and activator are linked by disulfide bridges. The activated enzyme derivative can be formed by a disulfide exchange reaction at alkaline pH or by an oxidation reaction which proceeds at neutral pH. The latter process requires O(2) and Cu(++), and is inhibited by EDTA.

Animals↗

Biosynthesis of the O antigen from Citrobacter 139.

The biosynthesis of the O antigen of Citrobacter 139 (Escherichia coli 3 Zurich 4,5,12:z(20)) was shown to proceed through a series of lipid-linked intermediates, similar to those involved in O-antigen synthesis in Salmonella. Galactose was the first sugar incorporated, followed by rhamnose and mannose. Abequose was incorporated from cytidine diphosphate (CDP)-abequose only when all three of the other nucleotide sugars (uridine diphosphate galactose, guanosine diphosphate mannose, and thymidine diphosphate rhamnose) were present. Rhamnosyl-galactosyl 1-phosphate and mannosyl-rhamnosyl-galactosyl 1-phosphate were identified as the products of mild alkaline hydrolysis of the lipid-linked intermediates.

Antigens↗