ホスホグルコムターゼ

Phosphoglucomutase-1

グリコーゲン代謝で重要。α配置のグルコースリン酸を変換する。欠損は糖原病14型
Short name=PGM 1
EC=5.4.2.2

Alternative name(s):

Glucose phosphomutase 1

Gene names

Name: PGM1

Function

This enzyme participates in both the breakdown and synthesis of glucose.

Catalytic activity

Alpha-D-glucose 1-phosphate = alpha-D-glucose 6-phosphate.

Cofactor

Binds 1 magnesium ion per subunit.

Subunit structure

Monomer.

Subcellular location

Isoform 1: Cytoplasm.

Polymorphism

Many polymorphic variants of PGM1 exist. 8 different alleles are known: PGM1*1+, PGM1*1-, PGM1*2+, PGM1*2-, PGM1*3+, PGM1*3-, PGM1*7+ and PGM1*7-. The sequence of PGM1*1+ is shown here.

Involvement in disease

Defects in PGM1 are the cause of glycogen storage disease type 14 (GSD14) [MIM:612934]. A metabolic disorder resulting in a myopathy characterized by exercise-induced intolerance with episodes of rhabdomyolysis, normal elevation of lactate, and hyperammonemia on a forearm-exercise test. Ref.16

Sequence similarities

Belongs to the phosphohexose mutase family.

Sequence caution

The sequence AAH90856.1 differs from that shown. Reason: Erroneous initiation.

ホスホグルコムターゼ２

リン酸化５炭糖を基質とする。
Short name=PGM 2
EC=5.4.2.2
Alternative name(s):
Glucose phosphomutase 2
Phosphodeoxyribomutase
Phosphopentomutase
EC=5.4.2.7

Function

Catalyzes the conversion of the nucleoside breakdown products ribose-1-phosphate and deoxyribose-1-phosphate to the corresponding 5-phosphopentoses. May also catalyze the interconversion of glucose-1-phosphate and glucose-6-phosphate. Has low glucose 1,6-bisphosphate synthase activity. Ref.8

Catalytic activity

Alpha-D-glucose 1-phosphate = alpha-D-glucose 6-phosphate.
Alpha-D-ribose 1-phosphate = D-ribose 5-phosphate.
2-deoxy-alpha-D-ribose 1-phosphate = 2-deoxy-alpha-D-ribose 5-phosphate.

Cofactor

Binds 1 magnesium ion per subunit By similarity.

Pathway

Carbohydrate degradation; 2-deoxy-D-ribose 1-phosphate degradation; D-glyceraldehyde 3-phosphate and acetaldehyde from 2-deoxy-alpha-D-ribose 1-phosphate: step 1/2.

Subcellular location

Cytoplasm By similarity.

Sequence similarities

Belongs to the phosphohexose mutase family.

Biophysicochemical properties

Kinetic parameters:
KM=45.7 µM for alpha-D-ribose 1-phosphate Ref.8
KM=4.1 µM for 2-deoxy-alpha-D-ribose 1-phosphate
KM=114 µM for alpha-D-glucose 1-phosphate
Vmax=104.3 µmol/min/mg enzyme with alpha-D-ribose 1-phosphate as substrate
Vmax=20.8 µmol/min/mg enzyme with 2-deoxy-alpha-D-ribose 1-phosphate as substrate
Vmax=22.8 µmol/min/mg enzyme with alpha-D-glucose 1-phosphate as substrate

Phosphoacetylglucosamine mutase

リン酸化GlcNAcを基質とする。UDP-GlcNAc、UDP-GalNAc合成経路に関与する。
Short name=PAGM
EC=5.4.2.3

Alternative name(s):

Acetylglucosamine phosphomutase
N-acetylglucosamine-phosphate mutase
Phosphoglucomutase-3
Short name=PGM 3

Gene names

Name: PGM3
Synonyms: AGM1

Function

Interconverts GlcNAc-6-P and GlcNAc-1-P.

Catalytic activity

N-acetyl-alpha-D-glucosamine 1-phosphate = N-acetyl-D-glucosamine 6-phosphate.

Cofactor

Binds 1 magnesium ion per subunit By similarity.

Pathway

Nucleotide-sugar biosynthesis; UDP-N-acetyl-alpha-D-glucosamine biosynthesis; N-acetyl-alpha-D-glucosamine 1-phosphate from alpha-D-glucosamine 6-phosphate (route I): step 2/2.

Tissue specificity

Found in many tissues except lung. Relatively high expression in pancreas, heart, liver, and placenta, and relatively low expression in brain, skeletal muscle and kidney.

Sequence similarities

Belongs to the phosphohexose mutase family.

Sequence caution

The sequence BAB14652.1 differs from that shown. Reason: Erroneous initiation.
The sequence CAI22635.1 differs from that shown. Reason: Erroneous gene model prediction.
The sequence CAI42427.1 differs from that shown. Reason: Erroneous gene model prediction.