The subunits of the heterodimeric capping protein CapZ possess a molecular mass of 34 kDa (α1 subunit) and 32 kDa (β2 subunit). CapZ binds with high affinity in a Ca++-independent manner to the barbed end of actin filaments (1:1000 M/M).
100 mM KCl, 20 mM Hepes pH 7.4, 1 mM DTT and 3% disaccharides, when reconstituted with 25 µl ultrapure water to obtain a 1.0 mg/ml solution.
Purity & Activity
Purity: >92% by scanning densitometry from Coomassie G-250 stained SDS-Gels.
Capping activity: F-actin (Cat.#: 8101) containing 20% pyrene actin (Cat.#: 8112) was incubated with CapZ and diluted below the critical concentration. Depolymerisation was followed by fluorometry and compared to an actin reference without CapZ.
Complete capping was obtained at a molar ratio of 1 : 1000 (CapZ : Actin). All proteins were used as supplied, i.e. without dialysis. G-Actin stock solutions were pre-spun 1 h, 100.000xg, 4°C.
Purification notes
CapZ has been finally purified by gel filtration on a Superdex 75 column.
Protein concentration
Determined by OD280 (0.1% = 1.234).
Storage instructions
CapZ stored at −70 °C upon arrival will be stable in performance for at least 6 months from the date of purchase. The solubilized protein is kept on ice and should be stored at -20°C in glycerol or CryoProtect (Cat.#: 6011-01). Avoid repeated freeze / thaw cycles.
Shipping conditions
At ambient temperature. Upon delivery store at -70°C.
Remarks
For Use in Research only. Not for Use in Human or Veterinary Diagnostical or Therapeutical Applications.
CAS no.
Proteins and buffers from Hypermol® are made of the ultrapure reagents in Milli-Q™ water, as described in our publications.