Phosphoglycerate mutase

Phosphoglycerate mutase
Phosphoglycerate mutase 1 (B type) dimer (human) according to PDB  1YFK
Properties of human protein
Mass / length primary structure	253/252/254/270 amino acids
Secondary to quaternary structure	Homodimer
Identifier
Gene names	PGAM1  ; PGAM2 ; PGAM4 ; PGAM5
Enzyme classification
EC, category	5.4.2.1 ,  isomerase
Response type	Rearrangement
Substrate	2-phosphoglycerate
Products	3-phosphoglycerate
Occurrence
Parent taxon	Creature

Phosphoglycerate mutases (PGAM) are enzymes that catalyze the rearrangement of the phosphate group in phosphoglycerate from the 2- to 3-position and vice versa . This reaction is a sub-step in glycolysis , the utilization of carbohydrates in the metabolism of all living things, which takes place in every cell . In mammals , additional alleles of the PGAM1 gene called PGAM2, PGAM4 and PGAM5 have formed by copying . PGAM2 is only produced in the muscles. Mutations in the PGAM2 gene lead to a form of muscular dystrophy .

Catalyzed reaction

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2-phosphoglycerate is rearranged to 3-phosphoglycerate and vice versa. The catalysis takes place through the interim formation of a phosphohistidine residue in the PGAM. It should be noted that an additional phosphate residue is attached to C2 and thus the intermediate product 2,3-BPG is created.

${\displaystyle \mathrm {{\text{Enz-His-Phosphat}}+{\text{3-Phosphoglycerat}}\rightleftharpoons } }$ ${\displaystyle \mathrm {{\text{Enz-His}}+{\text{2,3-Bisphosphoglycerat}}} }$

Only then is the phosphate residue at C3 removed and the mutase receives the phosphoryl group back in order to regenerate the phosphohistidine residue.

${\displaystyle \mathrm {{\text{Enz-His}}+{\text{2,3-Bisphosphoglycerat}}\rightleftharpoons } }$ ${\displaystyle \mathrm {{\text{Enz-His-Phosphat}}+{\text{2-Phosphoglycerat}}} }$

The enzyme requires catalytic amounts of 2,3-bisphosphoglycerate in order to keep the histidine residue in the active site in phosphorylated form.

More functions

The PGAM isoforms also have weak activity as bisphosphoglycerate mutase ( EC  5.4.2.4 ) and as bisphosphoglycerate phosphatase ( EC  3.1.3.13 ).

PGAM1 is produced in excess in cancer cells. PGAM1 binds to the core of the hepatitis C virus in vitro . Patients with autoimmune hepatitis produce increased levels of PGAM1 antibodies.

PGAM5 is transported to the outer membrane of mitochondria , where it binds Keap1 and Nrf2 .

Web links

Wikibooks: Biochemistry and Pathobiochemistry: Phosphoglycerate Mutase  - Learning and Teaching Materials

Individual evidence

1. ↑ Jeremy M. Berg, John L. Tymoczko, Lubert Stryer, Gregory J. Gatto, Jr.: Stryer Biochemistry . Springer-Verlag, 2014, ISBN 978-3-8274-2988-9 , pp. 467 ( limited preview in Google Book search).
2. ↑ F. Lu et al .: Serum proteomic-based analysis for the identification of a potential serological marker for autoimmune hepatitis. Biochem Biophys Res Commun . 367/2/ 2008 : 284-90. PMID 18154727
3. ↑ HX Su et al .: Screening cellular proteins binding to the core region of hepatitis C virus RNA genome with digoxin-labeled nucleic acids. Intervirology. 50/4/ 2007 : 303-9. PMID 17622790
4. ↑ LJ Huang et al .: Proteomic analysis of secreted proteins of non-small cell lung cancer. Ai Zheng. 25/11/ 2006 : 1361-7. PMID 17094902
5. ↑ SC Lo and M. Hannink: PGAM5 tethers a ternary complex Containing Keap1 and Nrf2 to the mitochondria. Exp Cell Res . 314/8/ 2008 : 1789-803. PMID 18387606