Glycine cleavage H-protein | |||||||||
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refined structures at 2 angstroms and 2.2 angstroms of the two forms of the h-protein, a lipoamide-containing protein of the glycine decarboxylase | |||||||||
Identifiers | |||||||||
Symbol | GCV_H | ||||||||
Pfam | PF01597 | ||||||||
Pfam clan | CL0105 | ||||||||
InterPro | IPR002930 | ||||||||
SCOP | 1htp | ||||||||
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Glycine cleavage T-protein, Aminomethyltransferase folate-binding domain | |||||||||
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crystal structure of a component of glycine cleavage system: t-protein from pyrococcus horikoshii ot3 at 1.5 a resolution | |||||||||
Identifiers | |||||||||
Symbol | GCV_T | ||||||||
Pfam | PF01571 | ||||||||
Pfam clan | CL0289 | ||||||||
InterPro | IPR006222 | ||||||||
SCOP | 1pj5 | ||||||||
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Glycine cleavage T-protein C-terminal barrel domain | |||||||||
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crystal structure of t-protein of the glycine cleavage system | |||||||||
Identifiers | |||||||||
Symbol | GCV_T_C | ||||||||
Pfam | PF08669 | ||||||||
InterPro | IPR013977 | ||||||||
SCOP | 1pj5 | ||||||||
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The glycine cleavage system is also known as the glycine decarboxylase complex or GCS. The system is a series of enzymes that are triggered in response to high concentrations of the amino acid glycine.[1] The glycine cleavage system is composed of four proteins: the T-protein, P-protein, L-protein, and H-protein. They do not form a stable complex,[2] so it is more appropriate to call it a "system" instead of a "complex"
Contents |
Name | EC number | Function |
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T-protein (GCST or AMT) | EC 2.1.2.10 | aminomethyltransferase |
P-protein (GLDC) | EC 1.4.4.2 | glycine dehydrogenase (decarboxylating) or just glycine dehydrogenase. |
L-protein (GCSL or DLD) | EC 1.8.1.4 | known by many names, but most commonly dihydrolipoyl dehydrogenase |
H-protein (GCSH) | is modified with lipoic acid and interacts with all other components in a cycle of reductive methylamination (catalysed by the P-protein), methylamine transfer (catalysed by the T-protein) and electron transfer (catalysed by the L-protein).[2] |
In plants the glycine cleavage system is coupled to serine hydroxymethyltransferase to give an overall reaction of:
This reaction, and by extension the glycine cleavage system, is required for photorespiration in C3 plants. Together the proteins involved in these reactions comprise about half the proteins in mitochondria from spinach and pea leaves.[2]
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