MW = 6.2 kDa calculated. GB1 (Immunoglobulin G-binding protein G, IgG-binding protein G) expressed in E. coli. The protein consists β-1 Immunoglobulin Binding Domain of Protein G, residues 303-357 (UniProtKB accession P19909), with the mutation T303Q (T2Q). This mutation reduces the cleavage of the N-terminal Met residue.
310 320 330 340 350 M-QYKLILNG KTLKGETTTE AVDAATAEKV FKQYANDNGV DGEWTYDDAT KTFTVTE
> 95% by SDS-PAGE. The protein is observed, in denaturing conditions, as a single band migrating at molecular weight below 14.4 kDa.
1 mg/mL solution in sodium phosphate 20 mM, pH 7. The concentration is calculated by the analysis of the absorbance at 280 nm (ε280= 9970 M-1cm-1 calculated).
Under the above described conditions, to avoid precipitation or protein aggregation, the product can be concentrated up to 3 mM.
-20°C. The protein is stable at 4°C for months at 25°C for at least two weeks. Avoid repeated freeze/thaw cycles.
NMR USE: after the experiments return the sample at 4°C.
Frericks Schmidt, H.L. et al. J. Phys. Chem. B 111 (51), 14362-14369 (2007).
Franks, W.T. et al. J. Am. Chem. Soc. 127 (35), 12291-12305 (2005).