Stereospecificity of sodium borohydride reduction of tyrosine decarboxylase from Streptococcus faecalis.

Stereospecificity of sodium borohydride reduction of tyrosine decarboxylase from Streptococcus faecalis.

Sodium boro[3H]hydride reduction of tyrosine decarboxylase from Streptococcus faecalis followed by complete hydrolysis of the enzyme produces epsilon-[3H]pyridoxyllysine. Degradation of this material to [4'-3H]pyridoxamine and stereochemical analysis with apoaspartate aminotransferase shows that the re side at C-4' of the cofactor is exposed to solvent at pH 5.5 and 7.0. After binding of L-tyro...

Studies on bacterial amino-acid decarboxylases: 2. l(-)-tyrosine decarboxylase from Streptococcus faecalis.

The reduction of cozymase by sodium borohydride.

Cozymase (diphosphopyridine nucleotide, DPN) has been assayed by a variety of biochemical and chemical methods (1). Among the simplest procedures has been the determination of the light absorption of reduced DPN at 340 rnp after reduction by sodium hydrosulfite. Since special precautions are required to remove completely the excess reducing agent which absorbs in this region, it appeared advant...

Sodium/proton antiporter in Streptococcus faecalis.

Streptococcus faecalis, like other bacteria, accumulates potassium ions and expels sodium ions. This paper is concerned with the pathway of sodium extrusion. Earlier studies (D.L. Heefner and F.M. Harold, Proc. Natl. Acad. Sci. USA 79:2798-2802, 1982) showed that sodium extrusion is effected by a primary, ATP-linked sodium pump. I report here that cells grown under conditions in which sodium AT...

Reduction of Chlorophyllides, Chlorophylls and Chlorophyll Derivatives by Sodium Borohydride.

Sodium borohydride is a well known reducing agent. In methanol at room temperature formyl and keto groups are readily reduced to alcohol groups, while ester and carboxyl groups, carbon-carbon and carbon-nitrogen double bonds are only reduced with difficulty (2, 17). Of the groups present in chlorophyll b the C3 formyl and the C9 keto groups should be amenable to reduction, while the C2 vinyl an...