Recombinant Human ST8SIA4 Protein, CF

R&D Systems | Catalog # 7027-GT

R&D Systems
100% Guarantee

Key Product Details

  • R&D Systems CHO-derived Recombinant Human ST8SIA4 Protein (7027-GT)
  • Quality control testing to verify active proteins with lot specific assays by in-house scientists
  • All R&D Systems proteins are covered with a 100% guarantee

Source

CHO

Accession Number

Q92187

Applications

Enzyme Activity
View all ST8 alpha-2,8-Sialyltransferase 4/ST8SIA4 Proteins and Enzymes »

Product Specifications

Source

Chinese Hamster Ovary cell line, CHO-derived human ST8 alpha-2,8-Sialyltransferase 4/ST8SIA4 protein
Gly40-Gln359, with an N-terminal 6-His tag

Purity

>95%, by SDS-PAGE under reducing conditions and visualized by Colloidal Coomassie® Blue stain at 5 μg per lane.

Endotoxin Level

<1.0 EU per 1 μg of the protein by the LAL method.

N-terminal Sequence Analysis

His

Predicted Molecular Mass

37 kDa

SDS-PAGE

55-66 kDa, reducing conditions

Activity

Measured by its ability to transfer sialic acid from CMP-NeuAc to Recombinant Human NCAM‑1/CD56 120 isoform (Catalog # 2408-NC).
The specific activity is >30 pmol/min/μg, as measured under the described conditions.

Formulation, Preparation, and Storage

7027-GT
Formulation Supplied as a 0.2 μm filtered solution in Tris, NaCl and Brij-35.
Shipping The product is shipped with dry ice or equivalent. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 6 months from date of receipt, -70 °C as supplied.
  • 3 months, -70 °C under sterile conditions after opening.

Background: ST8 alpha-2,8-Sialyltransferase 4/ST8SIA4

Polysialic acid (PSA), a glycan abundant on the neural cell adhesion molecule (NCAM) during embryonic development, negatively modulates the adhesive properties of NCAM (1). Following birth, PSA expression decreases promptly and becomes restricted to the hippocampus, hypothalamus, and olfactory bulb-areas of the brain that require continuous cell migration and synaptic plasticity (2). Expression of PSA in cancer cells has been suggested to increase tumor invasiveness and promote tumor growth (3). The temporal regulation of PSA is dependent on the expression of two polysialyltransferases, ST8SIA4 and ST8SIA2 (4, 5). While ST8SIA2 shows strict preference for NCAM (6), ST8SIA4 is also active on other glycoproteins, such as fetuin, in vitro (7). Unlike ST8SIA2, ST8SIA4 can catalyze both the initiation and polymerization of PSA. A combination of ST8SIA2 and ST8SIA4 cooperatively polysialylate NCAM, resulting in PSA with longer chains than when the enzymes are used individually (8). Disruption of ST8SIA4 in mice leads to impaired long-term potentiation and long-term depression of synapses of the adult hippocampus, similar to the phenotypes observed in NCAM‑deficient mice (9). Like most glycosyltransferases, ST8SIA4 may be a Golgi‑resident type II membrane protein. The activity of this enzyme has been measured with a phosphatase-coupled method (10).

References

  1. Scheidegger, E.P. et al. (1995) J. Biol. Chem. 270:22685.
  2. Rutishauser, U. (2008) Nat. Rev. Neurosci. 9:26.
  3. Seidenfaden, R. et al. (2003) Mol.Cell. Biol. 23:5908.
  4. Angata, K. et al. (1997) J. Biol. Chem. 272:7182.
  5. Ong, E. et al. (1998). Glycobiology 8:415.
  6. Korima, N. et al. (1996) J. Biol. Chem. 271:19457.
  7. Nakayama, J. and Fukuda, M. (1996) J. Biol. Chem. 271:1829.
  8. Angata, K. and Fukuda, M. (2002) J. Biol. Chem. 277:36808.
  9. Eckhardt, M. et al. (2000) J. Neurosci. 20:5234.
  10. Wu, Z.L. et al. (2011) Glycobiology 21:727.

Long Name

ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 4

Alternate Names

PST1, SIAT8-D, ST8SIAIV

Entrez Gene IDs

7903 (Human); 20452 (Mouse)

Gene Symbol

ST8SIA4

UniProt

Q92187

Additional ST8 alpha-2,8-Sialyltransferase 4/ST8SIA4 Products

Product Documents for Recombinant Human ST8SIA4 Protein, CF

Certificate of Analysis

To download a Certificate of Analysis, please enter a lot or batch number in the search box below.

Note: Certificate of Analysis not available for kit components.

Download SDS

Product Specific Notices for Recombinant Human ST8SIA4 Protein, CF

For research use only

Related Research Areas

Glycobiology-related Enzymes

Citations for Recombinant Human ST8SIA4 Protein, CF

Customer Reviews for Recombinant Human ST8SIA4 Protein, CF

There are currently no reviews for this product. Be the first to review Recombinant Human ST8SIA4 Protein, CF and earn rewards!

Have you used Recombinant Human ST8SIA4 Protein, CF?

Submit a review and receive an Amazon gift card!

$25/€18/£15/$25CAN/¥2500 Yen for a review with an image

$10/€7/£6/$10CAN/¥1110 Yen for a review without an image

Submit a review
Amazon Gift Card

Protocols

View specific protocols for Recombinant Human ST8SIA4 Protein, CF (7027-GT):

Materials
  • Assay Buffer: 100 mM MES, 10 mM MnCl2 (supplied in kit), pH 7.0
  • Recombinant Human alpha -2,8-Sialyltransferase 4/ST8SIA4 (rhST8SIA4) (Catalog # 7027-GT)
  • Donor Substrate: CMP-Sialic Acid (Sigma, Catalog # C8271), 10 mM stock in deionized water
  • Acceptor Substrate: Recombinant Human NCAM-1/CD56 120 isoform (rhNCAM-1) (Catalog # 2408-NC)
  • Sialyltransferase Activity Kit (R&D Systems, Catalog # EA002)
  • 96-well Clear Plate (Costar, Catalog # 92592)
  • Plate Reader (Model: SpectraMax Plus by Molecular Devices) or equivalent
  1. Dilute 1 mM Phosphate Standard by adding 40 µL of the 1 mM Phosphate Standard to 360 µL of Assay Buffer for a 100 µM stock.
  2. Prepare standard curve by performing six one-half serial dilutions of the 100 µM Phosphate stock in Assay Buffer. The standard curve has a range of 0.078 to 5 nmol per well.
  3. Reconstitute lyophilized rhNCAM-1/CD56 to 500 μg/mL in deionized water, 80 μg is needed for this protocol (do not reconstitute in PBS).
  4. Dilute CMP-Sialic Acid to 2.78 mM in Assay Buffer.
  5. Dilute Coupling Phosphatase 2 to 22.2 µg/mL in Assay Buffer.
  6. Prepare reaction mixture by combining 45 µL of 2.78 mM CMP-Sialic Acid, 45 µL of 22.2 µg/mL Coupling Phosphatase 2, and 160 µL of 500 μg/mL rhNCAM-1/CD56. (Volume is sufficient to test 10 wells.)
  7. Dilute rhST8SIA4 to 20 µg/mL in Assay Buffer.
  8. Load 50 µL of each dilution of the standard curve into a plate. Include a curve blank containing 50 μL of Assay Buffer.
  9. Load 25 µL of the 20 µg/mL rhST8SIA4 into the plate. Include a Control containing 25 µL of Assay Buffer.
  10. Start the reaction by adding 25 µL of reaction mixture to the wells, excluding the standard curve.
  11. Cover the plate with parafilm or a plate sealer and incubate at 37 °C for 20 minutes.
  12. Add 30 µL of the Malachite Green Reagent A to all wells.  Mix briefly.
  13. Add 100 µL of deionized water to all wells. Mix briefly.
  14. Add 30 µL of the Malachite Green Reagent B to all wells.  Mix and incubate for 20 minutes at room temperature.
  15. Read plate at 620 nm (absorbance) in endpoint mode.
  16. Calculate specific activity:

     Specific Activity (pmol/min/µg) =

 Phosphate released* (nmol) x (1000 pmol/nmol)
Incubation time (min) x amount of enzyme (µg)

     *Derived from the phosphate standard curve using linear or 4-parameter fitting and adjusted for Control.

Per Reaction:

  • rhST8SIA4: 0.5 μg
  • Coupling Phosphatase 2: 0.1 μg
  • rhNCAM-1/CD56: 8 μg
  • CMP-Sialic Acid: 0.25 mM

FAQs

No product specific FAQs exist for this product.

View all FAQs for Proteins and Enzymes