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P1261

Sigma-Aldrich

Phosphorylase a from rabbit muscle

lyophilized powder, 20-30 units/mg protein

Synonym(s):

1,4-α-D-Glucan:orthophosphate α-D-glucosyltransferase

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About This Item

CAS Number:
Enzyme Commission number:
EC Number:
MDL number:
UNSPSC Code:
12352204
NACRES:
NA.54

biological source

rabbit muscle

Quality Level

form

lyophilized powder

specific activity

20-30 units/mg protein

purified by

2× crystallization

composition

Protein, 30-60% E1%/280

foreign activity

AMP-phosphatase, ATP-phosphatase, debrancher enzyme and phosphorylase phosphatase ≤0.1%
phosphoglucomutase ≤0.25%
phosphorylase b ≤30%

storage temp.

−20°C

Related Categories

General description

Phosphorylase A is the active form of glycogen phosphorylase which converts glycogen and orthophosphate (Pi) to glucose 1-phoshate (G-1-P).

Application

Phosphorylase a from rabbit muscle has been used to mix with glycogen for the preparation of limit dextrin. It has also been used to probe the array in oligosaccharide microarray analysis of phosphorylase activity.
Phosphorylase from rabbit muscle has been used in a study to assess the molecular mechanisms of oleanolic acid. It has also been used in a study to describe the conversion of phosphorylase B to A, through a conversion enzyme in the presence of 32P-ATP.

Biochem/physiol Actions

Dimeric phosphorylase b is converted to the more active tetramer, phosphorylase a, by the action of phosphorylase kinase.
Phosphorylase A can be inhibited by these compounds: Polychlorinated biphenyls, polychlorinated biphenylols and polybrominated biphenyls.
Phosphorylase participates in glycogenolysis. Deficiency of phosphorylase leads to several glycogen storage diseases with hepatomegaly.

Unit Definition

One unit will form 1.0 μmole of α-D-glucose 1-phosphate from glycogen and orthophosphate per min at pH 6.8 at 30 °C, measured in a system containing phosphoglucomutase, NADP, and glucose-6-phosphate dehydrogenase. (One μmolar unit is equivalent to ~45 Cori units.)

Physical form

Lyophilized powder containing β-glycerophosphate and EDTA

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Regulatory Information

动植物源性产品

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  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

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  4. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  5. How is Phosphorylase A, Product P1261, prepared?

    To prepare Phosphorylase A (P1261), Sigma uses a method similar to the one described in the J. Biol.Chem., 231, 65 (1958).

  6. What is the final buffer Phosphorylase A, Product P1261, is in prior to lyophilization?

    The final buffer Phosphorylase A (P1261) is in prior to lyophilization is 0.1MB-glycerophosphate and 4 mM EDTA.

  7. What is the solubility of Phosphorylase A, Product P1261?

    Sigma tests solubility of Phosphorylase A (P1261) in water at a concentration of 1 mg/ml.

  8. What is the molecular weight of Phosphorylase A, Product P1261?

    The molecular weight of Rabbit Phosphorylase A (tetramer) is 370,000 per Biochemistry 6 (1967) p. 3315 (which was determined by sedimentation and "experiments in a variety of buffers, temperatures, and ionic strength").  The molecular weight by sequence analysis (Proc. Natl. Acad. Sci. USA, 74, 4762-4766) is 97,412.

  9. What is the pI of Phosphorylase A, Product P1261?

    The pI of Phosphorylase A (P1261) is 5.6 - 5.8.

  10. Has the amino acid sequence of phosphorylase from rabbit muscle been published?

    The sequence has been published. The amino acid composition is:Asp5l, Asn45, Thr35, Ser29, Glu64, Gln31, Pro36, Gly48, Ala63, Cys9, Val62, Met2l, Ile49, Leu79, Tyr36, Phe38, Trp12, Lys48, HiS22, and Arg63. Reference for the sequence and amino acid composition: K. Titani et al., Proc. Nat. Acad. Sci., USA, 74, 4762-4766 (1977) (see attached pdf).Product P1261 is phosphorylase a, which is the tetrameric form. Products P4649 and P6635 are phosphorylase b, the dimeric  form. The sequence information of the subunit would be the same for both forms.

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R C Mead et al.
Biochimica et biophysica acta, 701(2), 173-179 (1982-02-18)
Polychlorinated biphenyls, polychlorinated biphenylols and polybrominated biphenyls inhibited both rabbit muscle phosphorylase a and phosphorylase b (1,4-alpha-D-glucan:orthophosphate alpha-d-glucosyltransferase, EC 2.4.1.1). The degree of inhibition was dependent upon the relative hydrophobicity of the compounds and steric hinderance. 2,4,5,2',4',5'-Hexabromobiphenyl and Firemaster BP-6
Glycogen Phosphorylase Structures and Function
Fletterick, R. and S. Sprang
Accounts of Chemical Research, 15, 361-369 (1982)
Ian J Tetlow et al.
The Plant cell, 16(3), 694-708 (2004-02-20)
Protein phosphorylation in amyloplasts and chloroplasts of Triticum aestivum (wheat) was investigated after the incubation of intact plastids with gamma-(32)P-ATP. Among the soluble phosphoproteins detected in plastids, three forms of starch branching enzyme (SBE) were phosphorylated in amyloplasts (SBEI, SBEIIa
T C Chang et al.
Plant physiology, 80(2), 534-538 (1986-02-01)
A protein, starch phosphorylase inhibitor, was purified from the root of sweet potato (Ipomoea batatas [L.] Lam. cv Tainon 65). It had a molecular weight of 250,000 and could be composed of five identical subunits. The isoelectric point of the
Hypoglycemia in the toddler and child
Pediatric Endocrinology, Diabetes, and Metabolism, 920-955 (2014)

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