Merck
CN
All Photos(2)

Documents

P6635

Sigma-Aldrich

Phosphorylase b from rabbit muscle

lyophilized powder, ≥20 units/mg protein, 2× crystallization

Sign Into View Organizational & Contract Pricing
All Photos(2)
Synonym(s):
α-Glucan Phosphorylase, 1,4-α-D-Glucan:orthophosphate α-D-glucosyltransferase, Glycogen Phosphorylase
CAS Number:
9012-69-5
Enzyme Commission number:
2.4.1.1 (BRENDA, IUBMB)
EC Number:
232-737-0
MDL number:
MFCD00131905

biological source

rabbit muscle

form

lyophilized powder

specific activity

≥20 units/mg protein

mol wt

97,200 Da by calculation

purified by

2× crystallization

storage condition

(Keep container tightly closed in a dry and well-ventilated place)

technique(s)

mass spectrometry (MS): suitable

impurities

~0.01 μmol/mg protein 5′-AMP (This low level will not interfere with phosphorylase and phosphorylase kinase assays.)

UniProt accession no.

A0A5F9CLZ9
A0A5F9CRR0
A0A5F9D1C4
A0A5F9DLL9

foreign activity

phosphoglucomutase ≤1.0%
phosphorylase a ≤10%
phosphorylase kinase ≤0.5%
phosphorylase phosphatase, debrancher enzyme, AMPase and ATPase ≤0.1%

storage temp.

−20°C

Looking for similar products? Visit Product Comparison Guide

General description

Research area: Cell Signaling

Glycogen phosphorylase (PG), a specialized complex allosteric enzyme has an evolutionarily conserved gene sequence. GP contains a family of three isozymes such as muscle GP (mGP), liver GP (lGP), and brain GP (bGP) in humans.

Application

Phosphorylase b from rabbit muscle has been used:
  • in the calibration of Sepharose C1-6B columns while studying the molecular weight of methylamine dehydrogenase subunits
  • in ion mobility-mass spectrometry studies of phosphorylase B ions that have been generated with supercharging reagents, in the charge-reducing buffer
  • for the preparation of p32 labeled phosphorylase A using phosphorylase kinase and [32P]ATP
  • in phosphorylase phosphatase assay
  • in enzyme assay as a positive control to ensure the reaction system for the activity determination was adopted

Biochem/physiol Actions

Phosphorylase b is a non-active form and is present in resting muscles. Phosphorylase b kinase activity increases significantly when the Mg2+:ATP ratio exceeds 1. The breakdown of ATP during muscle contraction is thought to trigger in vivo conversion of phosphorylase b into a. Phosphorylase b is activated by inosine monophosphate. Glycogen phosphorylase (PG) enzyme plays a vital role in the first step of glycogenolysis. In the initial stage of glycogenolysis, glycogen phosphorylase(GP) breaks α-1,4- -glycosidic bonds, releasing the glucose-1-phosphate (G1P)molecule. When incubated with the proper concentrations of glucose-1-phosphate without the addition of primer, rabbit muscle phosphorylase B was found to be capable of forming protein-bound alpha-1,4 glucosyl chains.

Packaging

Package size based on protein content.

Unit Definition

One unit will form 1.0 μmole of α-D-glucose 1-phosphate from glycogen and orthophosphate in the presence of 5′-AMP, 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 approx. 45 Cori units.)

Physical form

Lyophilized powder containing lactose, 5′-AMP, and Mg(OAc)2 (10 μmole per 100 mg protein)

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

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Documents related to the products that you have purchased in the past have been gathered in the Document Library for your convenience.

Visit the Document Library

Difficulty Finding Your Product Or Lot/Batch Number?

Product numbers are combined with Pack Sizes/Quantity when displayed on the website (example: T1503-25G). Please make sure you enter ONLY the product number in the Product Number field (example: T1503).

Example:

T1503
Product Number
-
25G
Pack Size/Quantity

Additional examples:

705578-5MG-PW

PL860-CGA/SHF-1EA

MMYOMAG-74K-13

1000309185

enter as 1.000309185)

Having trouble? Feel free to contact Technical Service for assistance.

Lot and Batch Numbers can be found on a product's label following the words 'Lot' or 'Batch'.

Aldrich Products

  • For a lot number such as TO09019TO, enter it as 09019TO (without the first two letters 'TO').

  • For a lot number with a filling-code such as 05427ES-021, enter it as 05427ES (without the filling-code '-021').

  • For a lot number with a filling-code such as STBB0728K9, enter it as STBB0728 without the filling-code 'K9'.

Not Finding What You Are Looking For?

In some cases, a COA may not be available online. If your search was unable to find the COA you can request one.

Request COA

  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.

  3. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  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. 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.

  6. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

Cécile Mathieu et al.
The FEBS journal, 284(4), 546-554 (2016-10-27)
Glycogen phosphorylase (GP) is the key enzyme that regulates glycogen mobilization in cells. GP is a complex allosteric enzyme that comprises a family of three isozymes: muscle GP (mGP), liver GP (lGP), and brain GP (bGP). Although the three isozymes
Y Kida et al.
The Journal of clinical investigation, 89(2), 610-617 (1992-02-01)
Insulin-stimulated glycogen synthase activity in human muscle is reduced in insulin-resistant subjects. Insulin regulation of human muscle glycogen synthase may require activation of a type-1 protein phosphatase (PP-1). We investigated the change of phosphorylase phosphatase and glycogen synthase activities in
The conversion of lobster muscle phosphorylase a to b and phosphorylase b to a.
R W COWGILL
The Journal of biological chemistry, 234, 3154-3157 (1959-12-01)
J Tandecarz et al.
Molecular and cellular biochemistry, 16(2), 141-148 (1977-07-05)
Rabbit muscle phosphorylase b was found to be capable of forming protein bound alpha-1,4 glucosyl chains upon incubation of the enzyme with appropriate concentrations of glucose-1-phosphate with no primer addition (unprimed synthesis). This activity would only be present in a
Shanshan Qin et al.
Frontiers in plant science, 7, 1315-1315 (2016-09-16)
Two isoforms of starch phosphorylase (PHO; EC 2.4.1.1), plastidic PHO1 and cytosolic PHO2, have been found in all plants studied to date. Another starch phosphorylase-like gene, PHO3, which is an ortholog of Chlamydomonas PHOB, has been detected in some plant
View All Related Papers

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service