▍Backgound
Fibroblast growth factor-19 (FGF19) belongs to the large FGF family which has at least 23 members. All FGF family members are heparin binding growth factors with a core 120 amino acid (a.a.) FGF domain that allows for a common tertiary structure. FGFs are expressed during embryonic development and in restricted adult tissues. Four distinct but related classes of FGF receptors, FGF R1, 2, 3, and 4 exist. Unlike most FGFs which bind to and activate more than one FGF receptor, FGF19 is a specific ligand for FGF R4.
▍Source
Recombinant Human FGF-19 is expressed from Escherichia coli. It contains AA Leu 25 - Lys 216. The protein has a calculated MW of 24.2 kDa. This protein carries a polyhistidine tag at the N-terminus.
▍Endotoxin
Less than 1.0 EU per μg by the LAL method.
▍AA Sequence
MRPLAFSDAG PHVHYGWGDP IRLRHLYTSG PHGLSSCFLR IRADGVVDCA RGQSAHSLLE IKAVALRTVA IKGVHSVRYL CMGADGKMQG LLQYSEEDCA FEEEIRPDGY NVYRSEKHRL PVSLSSAKQR QLYKNRGFLP LSHFLPMLPM VPEEPEDLRG HLESDMFSSP LETDSMDPFG LVTGLEAVRS PSFEK
▍Purity
Purity >95% as determined by SDS-PAGE.
▍Formulation
Lyophilized from 0.22 μm filtered solution in PBS, 0.3 M NaCl, 0.3 M Arginine, pH7.4. Normally trehalose is added as protectant before lyophilization.
▍Reconstitution
Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at < -20°C. Further dilutions should be made in appropriate buffered solutions.
▍Storage
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
This product is stable after storage at:
-20°C to -70°C for 12 months in lyophilized state;
-70°C for 3 months under sterile conditions after reconstitution.
▍SDS-PAGE
Human FGF-19, His Tag on SDS-PAGE under reducing (R) condition. The gel was stained overnight with Coomassie Blue. The purity of the protein is greater than 95%.