Cobalt(III), a probe of metal binding sites of Escherichia coli alkaline phosphatase.

Metal specificity is correlated with two crucial active site residues in Escherichia coli alkaline phosphatase.

Escherichia coli alkaline phosphatase exhibits maximal activity when Zn(2+) fills the M1 and M2 metal sites and Mg(2+) fills the M3 metal site. When other metals replace the zinc and magnesium, the catalytic efficiency is reduced by more than 5000-fold. Alkaline phosphatases from organisms such as Thermotoga maritima and Bacillus subtilis require cobalt for maximal activity and function poorly ...

Nucleotide sequence of the gene for alkaline phosphatase of Thermus caldophilus GK24 and characteristics of the deduced primary structure of the enzyme.

The gene encoding Thermus caldophilus GK24 (Tca) alkaline phosphatase was cloned into Escherichia coli. The primary structure of Tca alkaline phosphatase was deduced from its nucleotide sequence. The Tca alkaline phosphatase precursor, including the signal peptide sequence, was comprised of 501 amino acid residues. Its molecular mass was determined to be 54¿ omitted¿760 Da. On the alignment of ...

Studies on the active center of alkaline phosphatase of E. coli.

Alkaline phosphatase of E. coli is a zinc metalloenzyme,' and the activity of the enzyme can be reversibly abolished and restored by the removal and addition of zinc ions at the active site.3 The metal has also been thought to stabilize the structure of the enzyme.4 When assayed in 1 M Tris buffer, pH 8.0, the activity, measured by formation of p-nitrophenol from p-nitrophenylphosphate, is sign...

Escherichia coli alkaline phosphatase. Metal binding, protein conformation, and quaternary structure.

Altering of the metal specificity of Escherichia coli alkaline phosphatase.

Analysis of sequence alignments of alkaline phosphatases revealed a correlation between metal specificity and certain amino acid side chains in the active site that are metal-binding ligands. The Zn(2+)-requiring Escherichia coli alkaline phosphatase has an Asp at position 153 and a Lys at position 328. Co(2+)-requiring alkaline phosphatases from Thermotoga maritima and Bacillus subtilis have a...