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Sandbox Reserved 773
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| This Sandbox is Reserved from Sep 25, 2013, through Mar 31, 2014 for use in the course "BCH455/555 Proteins and Molecular Mechanisms" taught by Michael B. Goshe at the North Carolina State University. This reservation includes Sandbox Reserved 299, Sandbox Reserved 300 and Sandbox Reserved 760 through Sandbox Reserved 779. |
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Histidine Decarboxylase
Histidine Decarboxylase (HDC) is an enzyme that is responsible for converting histamine from amino acid L-histidine. This enzyme belongs in the group II pyridoxal-5-phosphate (PLP)-dependent decarboxylase family. As the name suggested, this enzyme catalyzes the production of histamine by the removal of carboxylate group from the amino acid L-histidine whilst utilize pyridoxal phosphate as a cofactor. The mammalian Histamine decarboxylase is originated from HDC gene which encodes a 74kDa precursor polypeptide. However, the enzyme becomes active when its C-terminal is truncated into 54kDa during post-translation process. [1] [2] [3]
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General Information
Histidine Decarboxylase
Symbol: HDC
Gene Name: HDC gene
Organism: Homo sapiens
Classification: Lyase
Length: 481 residues [4]
Chains: A, B, C, D, E, F [4]
Molecular Weight: 54314.8 kDa per chain [4]
Isoelectric Point: 5.4 (mouse HDC) [5] [2]
Km: 0.1 mM (human)[6] [7], 0.29mM (mouse stomach)[5], 0.26mM (mouse mastocytoma P-815 cells) [2]
Vmax: 1880 nmol/min/mg
Sequence and Structure
Histidine Decarboxylase is considered to be a homo-dimer when one observe its biological assembly. A homo-dimer is a quaternary structure (link) formed by, usually non-covalently bound, identical monomers or protein chains. In human, three human HDC (hHDC) homo-dimers can be joined together to form a trimer asymmetric unit. [6], [8]
