Tau (K18) Wild-Type Pre-formed Fibrils

Human Recombinant Tau (K18) Wild-Type PFFs

Catalog No. SPR-525

0 out of 5 based on 0 customer ratings
Reviews (0) | Datasheet
Expression System E. coli
Tags No tag
SKU: SPR-525 Category:

Clear
Bulk Quote
SPR-525_Tau-K18-Wild-Type-Pre-formed-Fibrils-Protein-SDS-Page-1.png
TEM of Tau (K18) Wild-Type Pre-formed Fibrils (SPR-525)Sedimentation assay of Tau (K18) Wild-Type Pre-formed Fibrils (SPR-525)Thioflavin T assay of Tau (K18) Wild-Type Pre-formed Fibrils (SPR-525)TEM of Tau (K18) Wild-Type Pre-formed Fibrils (SPR-525)
Product Name Tau (K18) Wild-Type Pre-formed Fibrils
Description

Human Recombinant Tau (K18) Wild-Type PFFs
Applications WB, SDS-PAGE, In vivo assay, In vitro assay
Concentration 2 mg/mL
Conjugates No tag
Dylight 488
Overview:

  • High fluorescence yield
  • High photostability
  • Less pH-sensitive
  • Excellent batch-to-batch reproducibility
  • Stringently QC tested
  • Molecular weight: 1011 g/mol

Dylight 488 Datasheet

 Dylight 488 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 493 nm

λem = 518 nm

εmax = 7.0×104

Laser = 488 nm

 

APC/Cy7
Overview:

  • High quantum yield
  • Excellent batch-to-batch reproducibility
  • Stringently QC tested

APC-Cy7 Datasheet

 

 ACP-Cy7 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 652 nm

λem = 790 nm

Laser = 594 or 633 nm

 

 

  Dylight 350
Overview:

  • High fluorescence intensity
  • High photostability
  • Less pH-sensitive
  • Excellent solubility in water
  • Stringently QC tested
  • Excellent batch-to-batch reproducibility
  • Molecular weight: 874 g/mol

Dylight 350 Datasheet

 Dylight 350 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 353 nm

λem = 432 nm

εmax = 1.5×104

 

 

  Dylight 405
Overview:

  • High fluorescence intensity
  • High photostability
  • Less pH-sensitive
  • Excellent batch-to-batch reproducibility
  • Stringently QC tested
  • Molecular weight: 793 g/mol

Dylight 405 Datasheet

 Dylight 405 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 400 nm

λem = 420 nm

εmax = 3.0×104

Laser = 405 nm

 

Dylight 594
Overview:

  • High fluorescence yield
  • High photostability
  • Less pH-sensitive
  • Excellent batch-to-batch reproducibility
  • Stringently QC tested
  • Molecular weight: 1078 g/mol

Dylight 594 Datasheet

 Dylight 594 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 593 nm

λem = 618 nm

εmax = 8.0×104

Laser = 526 nm

 

 Dylight 633
Overview:

  • High fluorescence yield
  • High photostability
  • Less pH-sensitive
  • Excellent batch-to-batch reproducibility
  • Stringently QC tested
  • Molecular weight: 1066 g/mol

Dylight 633 Datasheet

 Dylight 633 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 638 nm

λem = 658 nm

εmax = 1.7×105

Laser = 633 nm

 

 PerCP 
Overview:

  • Peridinin-Chlorophyll-Protein Complex
  • Small phycobiliprotein
  • Isolated from red algae
  • Large stokes shift (195 nm)
  • Molecular Weight: 35 kDa
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

PerCP Datasheet

  PerCP Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 482 nm

λem = 677 nm

εmax = 1.96 x 106

Laser = 488 nm

 

 PE/ATTO 594
PE/ATTO 594 is a tandem conjugate, where PE is excited at 535 nm and transfers energy to ATTO 594 via FRET (fluorescence resonance energy transfer), which emits at 627 nm.
Overview:

  • High fluorescence yield
  • High photostability
  • Very hydrophilic
  • Excellent solubility in water
  • Very little aggregation

PE/ATTO 594 Datasheet

 PE-ATTO 594 Fluorophore Conjugate Excitation and Emission Spectra Optical Properties:

λex = 535 nm

λem = 627 nm

Laser = 488 to 561 nm

 

  FITC (Fluorescein)
Overview:

  • Excellent fluorescence quantum yield
  • High rate of photobleaching
  • Good solubility in water
  • Broad emission spectrum
  • pH dependent spectra
  • Molecular formula: C20H12O5
  • Molar mass: 332.3 g/mol
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

FITC-Fluorescent-conjugate

 FITC Fluorescein Fluorophore Excitation and Emission Spectra Optical Properties:

λex = 494 nm

λem = 520 nm

εmax = 7.3×104

Φf = 0.92

τfl = 5.0 ns

Brightness = 67.2

Laser = 488 nm

Filter set = FITC

 

 ATTO 700
Overview:

  • High fluorescence yield
  • Excellent thermal and photostability
  • Quenched by electron donors
  • Very hydrophilic
  • Good solubility in polar solvents
  • Zwitterionic dye
  • Molar Mass: 575 g/mol

ATTO 700 Datasheet

  ATTO 700 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 700 nm

λem = 719 nm

εmax = 1.25×105

Φf = 0.25

τfl = 1.6 ns

Brightness = 31.3

Laser = 676 nm

Filter set = Cy®5.5

 

 ATTO 680
Overview:

  • High fluorescence yield
  • Excellent thermal and photostability
  • Quenched by electron donors
  • Very hydrophilic
  • Good solubility in polar solvents
  • Zwitterionic dye
  • Molar Mass: 631 g/mol

ATTO 680 Datasheet

  ATTO 680 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 680 nm

λem = 700 nm

εmax = 1.25×105

Φf = 0.30

τfl = 1.7 ns

Brightness = 37.5

Laser = 633 – 676 nm

Filter set = Cy®5.5

 

 ATTO 655
Overview:

  • High fluorescence yield
  • High thermal and photostability
  • Excellent ozone resistance
  • Quenched by electron donors
  • Very hydrophilic
  • Good solubility in polar solvents
  • Zwitterionic dye
  • Molar Mass: 634 g/mol

ATTO 655 Datasheet

 ATTO 655 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 663 nm

λem = 684 nm

εmax = 1.25×105

Φf = 0.30

τfl = 1.8 ns

Brightness = 37.5

Laser = 633 – 647 nm

Filter set = Cy®5

 

 ATTO 633
Overview:

  • High fluorescence yield
  • High thermal and photostability
  • Moderately hydrophilic
  • Good solubility in polar solvents
  • Stable at pH 4 – 11
  • Cationic dye, perchlorate salt
  • Molar Mass: 652.2 g/mol

ATTO 633 Datasheet

 ATTO 633 Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 629 nm

λem = 657 nm

εmax = 1.3×105

Φf = 0.64

τfl = 3.2 ns

Brightness = 83.2

Laser = 633 nm

Filter set = Cy®5

 

 ATTO 594
Overview:

  • High fluorescence yield
  • High photostability
  • Very hydrophilic
  • Excellent solubility in water
  • Very little aggregation
  • New dye with net charge of -1
  • Molar Mass: 1137 g/mol
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

ATTO 594 Datasheet

  ATTO 594 Fluorophore Excitation and Emission Spectrum Optical Properties:

λex = 601 nm

λem = 627 nm

εmax = 1.2×105

Φf = 0.85

τfl = 3.5 ns

Brightness = 102

Laser = 594 nm

Filter set = Texas Red®

 

 ATTO 565
Overview:

  • High fluorescence yield
  • High thermal and photostability
  • Good solubility in polar solvents
  • Excellent solubility in water
  • Very little aggregation
  • Rhodamine dye derivative
  • Molar Mass: 611 g/mol

ATTO 565 Datasheet

  ATTO 565 Fluorophore Excitation and Emission Spectra Optical Properties:

λex = 563 nm

λem = 592 nm

εmax = 1.2×105

Φf = 0.9

τfl = 3.4 n

Brightness = 10

Laser = 532 nm

Filter set = TRITC

 

  ATTO 488
Overview:

  • High fluorescence yield
  • High photostability
  • Very hydrophilic
  • Excellent solubility in water
  • Very little aggregation
  • New dye with net charge of -1
  • Molar Mass: 804 g/mol
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications. 

ATTO 488 Datasheet

   ATTO 488 Fluorophore Excitation and Emission Spectra Optical Properties:

λex = 501 nm

λem = 523 nm

εmax = 9.0×104

Φf = 0.80

τfl = 4.1 ns

Brightness = 72

Laser = 488 nm

Filter set = FITC

 

  ATTO 390
Overview:

  • High fluorescence yield
  • Large Stokes-shift (89 nm)
  • Good photostability
  • Moderately hydrophilic
  • Good solubility in polar solvents
  • Coumarin derivate, uncharged
  • Low molar mass: 343.42 g/mol
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications. 

ATTO 390 Datasheet

 ATTO 390 Fluorescent Dye Excitation and Emission Spectra Optical Properties:

λex = 390 nm

λem = 479 nm

εmax = 2.4×104

Φf = 0.90

τfl = 5.0 ns

Brightness = 21.6

Laser = 365 or 405 nm

 

APC (Allophycocyanin)
Overview:

  • High quantum yield
  • Large phycobiliprotein
  • 6 chromophores per molecule
  • Isolated from red algae
  • Molecular Weight: 105 kDa
  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

APC Datasheet

  APC Fluorophore Absorption and Emission Spectrum Optical Properties:

λex = 650 nm

λem = 660 nm

εmax = 7.0×105

Φf = 0.68

Brightness = 476

Laser = 594 or 633 nm

Filter set = Cy®5

 

Streptavidin

Properties:

  • Homo-tetrameric protein purified from Streptomyces avidinii which binds four biotin molecules with extremely high affinity
  • Molecular weight: 53 kDa
  • Formula: C10H16N2O3S
  • Applications: Western blot, immunohistochemistry, and ELISA

Streptavidin Datasheet

BiotinBiotin Conjugate Structure

Properties:

  • Binds tetrameric avidin proteins including Streptavidin and neuravidin with very high affinity
  • Molar mass: 244.31 g/mol
  • Formula: C10H16N2O3S
  • Applications: Western blot, immunohistochemistry, and ELISA*

*The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

Biotin Datasheet

HRP (Horseradish peroxidase)

Properties:

  • Enzymatic activity is used to amplify weak signals and increase visibility of a target
  • Readily combines with hydrogen peroxide (H2O2) to form HRP-H2O2 complex which can oxidize various hydrogen donors
  • Catalyzes the conversion of:
    • Chromogenic substrates (e.g. TMB, DAB, ABTS) into coloured products
    • Chemiluminescent substrates (e.g. luminol and isoluminol) into light emitting products via enhanced chemiluminescence (ECL)
    • Fluorogenic substrates (e.g. tyramine, homovanillic acid, and 4-hydroxyphenyl acetic acid) into fluorescent products
  • High turnover rate enables rapid generation of a strong signal
  • 44 kDa glycoprotein
  • Extinction coefficient: 100 (403 nm)
  • Applications: Western blot, immunohistochemistry, and ELISA*
    • *The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

HRP Datasheet

AP (Alkaline Phosphatase)

Properties:

  • Broad enzymatic activity for phosphate esters of alcohols, amines, pyrophosphate, and phenols
  • Commonly used to dephosphorylate the 5’-termini of DNA and RNA to prevent self-ligation
  • Catalyzes the conversion of:
    • Chromogenic substrates (e.g. pNPP, naphthol AS-TR phosphate, BCIP) into coloured products
    • Fluorogenic substrates (e.g. 4-methylumbelliferyl phosphate) into fluorescent products
  • Molecular weight: 140 kDa
  • Applications: Western blot, immunohistochemistry, and ELISA

AP Datasheet

  R-PE (R-Phycoerythrin)
Overview:

  • Broad excitation spectrum
  • High quantum yield
  • Photostable
  • Member of the phycobiliprotein family
  • Isolated from red algae
  • Excellent solubility in water
  • Molecular Weight: 250 kDa

 

  • Applications: The listed applications provide a general overview of potential uses for conjugated antibodies. However, they do not guarantee that every antibody-conjugate combination has been tested or validated for these specific applications.

R-PE Datasheet

  R-PE Fluorophore Excitation and Emission Spectra Optical Properties:

λex = 565 nm

λem = 575 nm

εmax = 2.0×106

Φf = 0.84

Brightness = 1.68 x 103

Laser = 488 to 561 nm

Filter set = TRITC

 
Nature Recombinant
Species Human
Expression System E. coli
Amino Acid Sequence MSRLQTAPVPMPDLKNVKSKIGSTENLKHQPGGGKVQIINKKLDLSNVQSKCGSKDNIKHVPGGGSVQIVYKPVDLSKVTSKCGSLGNIHHKPGGGQVEVKSEKLKDFDRVQSKIGSLDNITHVPGGGNKKIETHKLTFRE
Purity >95%
Other Resources Sonication Protocol
Protein Length 141 amino acids
Protein Size 15.18 kDa
Field of Use Not for use in humans. Not for use in diagnostics or therapeutics. For in vitro research use only.

Properties

Storage Buffer 10 mM HEPES pH 7.4, 100 mM NaCl
Storage Temperature -80ºC
Shipping Temperature Dry Ice. Shipping note: Product will be shipped separately from other products purchased in the same order.
Purification Ion-exchange Purified
Cite This Product Human Recombinant Tau (K18) Wild-Type Pre-formed Fibrils (StressMarq Biosciences | Victoria, BC CANADA | Catalog# SPR-525)
Certificate of Analysis Certified > 95% pure via SDS-PAGE and A260/A280 ratio
Other Relevant Information Product is wildtype equivalent of Catalog No. SPR-330. Corresponding monomer is SPR-524.

Biological Description

Alternative Names Tau, Microtubule-associated Tau, Microtubule-associated protein Tau, MAPT, MAP, Tau-441, Tau-412, Tau-381, Tau-352, Paired Helical Filament-Tau, PHF-Tau, Neurofibrillary Tangle Tau, G Beta/Gamma Subunit-Interacting Factor 1, Isoform 4, Tubulin-associated unit
Research Areas Alzheimer's Disease, Neurodegeneration, Neuroscience, Tangles & Tau
Swiss Prot P10636
Scientific Background Tauopathies are a class of neurodegenerative diseases characterized by the pathological aggregation of tau protein into insoluble fibrils that disrupt neuronal function. The K18 fragment, which includes the four microtubule-binding repeat domains of tau, is frequently used in experimental models due to its propensity to form fibrillar aggregates. Kumar & Udgaonkar (2022) observed that tau K18 wildtype fibrils exhibit distinct structural features compared to mutant forms, with the wildtype fibrils catalyzing aggregation of monomeric tau more efficiently. StressMarq’s Human Recombinant Tau (K18) Wild-Type Pre-Formed Fibrils have been demonstrated to seed monomers in an in-vitro ThT seeding assay.
References Boyarko, B., & Hook, V. (2021). Human tau isoforms and proteolysis for production of toxic tau fragments in neurodegeneration. Frontiers in Neuroscience, 15, 702788. https://doi.org/10.3389/fnins.2021.702788
Kumar, H., & Udgaonkar, J. B. (2022). Elongation of fibrils formed by a tau fragment is inhibited by a transient dimeric intermediate. The Journal of Physical Chemistry B, 126(18), 3385–3397. https://doi.org/10.1021/acs.jpcb.1c10752
Zeng, Y., Yang, J., Zhang, B., Gao, M., Su, Z., & Huang, Y. (2020). The structure and phase of tau: From monomer to amyloid filament. Cellular and Molecular Life Sciences, 78, 1873–1886. https://doi.org/10.1007/s00018-020-03681-x
Zhang, X., Wang, J., Zhang, Z., & Ye, K. (2024). Tau in neurodegenerative diseases: Molecular mechanisms, biomarkers, and therapeutic strategies. Translational Neurodegeneration, 13(40). https://doi.org/10.1186/s40035-024-00429-6

Product Images

<p>SDS-PAGE analysis of the starting material used for fibrillization, purified Human Tau (K18) Wild-Type Monomers, on a 12% Bis-Tris gel.</p>

SDS-PAGE analysis of the starting material used for fibrillization, purified Human Tau (K18) Wild-Type Monomers, on a 12% Bis-Tris gel.

<p>Representative TEM image of Tau (K18) Wild-Type Pre-formed Fibrils, 200nm scale. Negative stain transmission electron microscopy images of SPR-525 acquired at 80 Kv on carbon coated 400 mesh copper grids using phosphotungstic acid and uranyl acetate stain.</p>

Representative TEM image of Tau (K18) Wild-Type Pre-formed Fibrils, 200nm scale. Negative stain transmission electron microscopy images of SPR-525 acquired at 80 Kv on carbon coated 400 mesh copper grids using phosphotungstic acid and uranyl acetate stain.

<p>Sedimentation assay on Tau (K18) Wild-Type Pre-formed Fibrils. Samples were spun down at 15,000 x g, washed, and then spun down again. Fibril samples are prepared in denaturing conditions prior to running on the gel. SDS-PAGE analysis on a 12% Bis-Tris gel shows that the majority of the fibril is insoluble.</p>

Sedimentation assay on Tau (K18) Wild-Type Pre-formed Fibrils. Samples were spun down at 15,000 x g, washed, and then spun down again. Fibril samples are prepared in denaturing conditions prior to running on the gel. SDS-PAGE analysis on a 12% Bis-Tris gel shows that the majority of the fibril is insoluble.

<p>In vitro seeding activity of Tau (K18) Wild-Type Pre-formed Fibrils in a ThT assay. The fibrils (SPR-525) seed fibril formation of Tau (K18) Wild-Type Monomers (SPR-524) over 72 hours. Reactions (100uL) shaken at 600 rpm in Greiner-Bio 96 Well Non-Binding Cell Culture Microplates, Black (Greiner-Bio Catalog #655900) at 37oC in the presence of 25 uM ThT and read with an XPS Microplate Reader set at 450nmex/485nmem.</p>

In vitro seeding activity of Tau (K18) Wild-Type Pre-formed Fibrils in a ThT assay. The fibrils (SPR-525) seed fibril formation of Tau (K18) Wild-Type Monomers (SPR-524) over 72 hours. Reactions (100uL) shaken at 600 rpm in Greiner-Bio 96 Well Non-Binding Cell Culture Microplates, Black (Greiner-Bio Catalog #655900) at 37oC in the presence of 25 uM ThT and read with an XPS Microplate Reader set at 450nmex/485nmem.

<p>Representative TEM image of Tau (K18) Wild-Type Pre-formed Fibrils, 500nm scale. Negative stain transmission electron microscopy images of SPR-525 acquired at 80 Kv on carbon coated 400 mesh copper grids using phosphotungstic acid and uranyl acetate stain.</p>

Representative TEM image of Tau (K18) Wild-Type Pre-formed Fibrils, 500nm scale. Negative stain transmission electron microscopy images of SPR-525 acquired at 80 Kv on carbon coated 400 mesh copper grids using phosphotungstic acid and uranyl acetate stain.

Reviews

Reviews

There are no reviews yet.

Be the first to review “Tau (K18) Wild-Type Pre-formed Fibrils”

Your email address will not be published. Required fields are marked *