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Alkaline phosphatase (EC 3.1.3.1) (ALP) [1] is a zinc and magnesium-containing metalloenzyme which hydrolyzes phosphate esters, optimally at high pH. It is found in nearly all living organisms, with the exception of some plants. In Escherichia coli, ALP (gene phoA) is found in the periplasmic space. In yeast it (gene PHO8) is found in lysosome-like vacuoles and in mammals, it is a glycoprotein attached to the membrane by a GPI-anchor.

In mammals, four different isozymes are currently known [2]. Three of them are tissue-specific: the placental, placental-like (germ cell) and intestinal isozymes. The fourth form is tissue non-specific and was previously known as the liver/bone/kidney isozyme.

Streptomyces' species involved in the synthesis of streptomycin (SM), an antibiotic, express a phosphatase (EC 3.1.3.39) (gene strK) which is highly related to ALP. It specifically cleaves both streptomycin-6-phosphate and, more slowly, streptomycin-3"-phosphate.

A serine is involved in the catalytic activity of ALP. The region around the active site serine is relatively well conserved and can be used as a signature pattern.

June 1994 / Text revised.

PROSITE method (with tools and information) covered by this documentation:

ALKALINE_PHOSPHATASE, PS00123; Alkaline phosphatase active site  (PATTERN)

Consensus pattern: [IV]-x-D-S-[GAS]-[GASC]-[GAST]-[GA]-T S is the active site residue Sequences known to belong to this class detected by the pattern: ALL Other sequence(s) detected in Swiss-Prot: 3

• Retrieve an alignment of Swiss-Prot true positive hits:   Clustal format, color, condensed view  / Clustal format, color  / Clustal format, plain text  / Fasta format • Retrieve the sequence logo from the alignment • Taxonomic tree view of all Swiss-Prot/TrEMBL entries matching PS00123 • Retrieve a list of all Swiss-Prot/TrEMBL entries matching PS00123 • Scan Swiss-Prot/TrEMBL entries against PS00123 • view ligand binding statistics

Matching PDB structures: 1AJA 1AJB 1AJC 1AJD ... [ALL]

1	Authors	Trowsdale J., Martin D., Bicknell D., Campbell I.
	Title	Alkaline phosphatases.
	Source	Biochem. Soc. Trans. 18:178-180(1990).
	PubMed ID	2379681

2	Authors	Manes T., Glade K., Ziomek C.A., Millan J.L.
	Title	Genomic structure and comparison of mouse tissue-specific alkaline phosphatase genes.
	Source	Genomics 8:541-554(1990).
	PubMed ID	2286375

3	Authors	Mansouri K., Piepersberg W.
	Title	Genetics of streptomycin production in Streptomyces griseus: nucleotide sequence of five genes, strFGHIK, including a phosphatase gene.
	Source	Mol. Gen. Genet. 228:459-469(1991).
	PubMed ID	1654502

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