Use less protein and accelerate the process of crystallizing membrane proteins using the new patent-pending Memb-PASS™ (Prompt Assay of Size and Stability) technology, developed by Dr. Michael Wiener and members of his laboratory at the University of Virginia.

The Memb-PASS™ Differential Filtration Detergent Assay (DFDA) consists of 94 carefully selected and non-denaturing detergents which are used in combination with the Memb-PASS™ High and Low MWCO Filtration Plates to rapidly screen your integral membrane proteins for proper detergent selection in the preparation for crystallization trials.

The membrane protein of interest is first bound to an affinity matrix and aliquoted into a 96-well microplate. Each well containing the immobilized protein is then washed extensively in the new detergent and finally eluted in that new detergent into a collection plate. Protein that is not stable in the new detergent is precipitated on the resin and not present in the elutions. Half of the elution is passed through an Memb-PASS™ High MWCO Filtration Plate and the other half through an Memb-PASS™ Low MWCO Filtration Plate. Protein amounts of both elution plates are quantified e.g. by Western Blot. The high MWCO provides readout on stability while the ratio of the low/high MWCO plate provides information on the relative protein detergent complex (PDC) size.
Once the protein is exchanged into a new suitable detergent, the Memb-PASS™ Solubility Screen should be set up to determine the proper protein concentration for crystallization.

The Memb-PASS™ product line is specifically designed to work together and helps you significantly reduce the amount of protein, reagents and time spent on the crystallization of membrane proteins.

Flyer Memb-PASS^TM (PDF, 1.1 MB)

   Memb-PASS™ Differential Filtration Detergent Assay Manual

Nonsaleable to USA!

[1] Vergis et al. (2010) A high-throughput differential filtration assay to screen and select detergents for membrane proteins. Anal. Biochem. 407:1.
[2] Vergis et al. (2011) The variable detergent sensitivity of proteases that are utilized for recombinant protein affinity tag removal. Prot. Expr. Purif. 78:139.

Please contact xtals@jenabioscience.com with questions or inquiries.