Polyoxyethylene detergents, also known as Alkyl PEGs, have the general formula CnEm. One of the main advantages of the polyoxyethylene detergents is the ability to vary both the chain length (Cn) and the headgroup size (Em). This allows researchers to easily compare protein behavior across the family of detergents, similar to glucosides and maltosides, where either the headgroup or tailgroup is a repeat of some moiety. Polyoxyethylene detergents with shorter tail lengths (e.g. C6E3 – PN T330) tend to be harsher, have a lower CMC, and form larger micelles than detergents with longer tail lengths (e.g. C12E8 – PN O330), which is a gentler detergent with a higher CMC and smaller micelle size.
These detergents have a history of long use in membrane protein biochemistry. The detergent, C8E4 (T350), has been primarily used in a number of bacterial outer membrane β-barrel proteins, including the E. coli FimD translocation channel(1) and the vitamin B12 transporter BtuB(2). Other structures determined using polyoxyethylene detergents include the 7 TM helix Ste24p CaaX protease(3), which was purified and crystallized using C12E7 (PN H370); the 12 TM helix multidrug ABC transporter SAV1866(4), which was purified and crystallized in C12E8 (PN O330); and the 5 TM helix Nitrate Reductase A(5), which was purified and crystallized using C12E9 (PN APO129). The full family of all of the Alkyl PEG detergents offered by Anatrace is also available as part of the detergent panel in the Analytic Selector Kit, a high throughput assay for the selection of detergents for crystallization studies.
New Anatrace Alkyl PEGS
1. Phan, G. et al. (2011) Nature 474, 49-53 (PDB: 3OHN).
2. Chimento, D. P. et al. (2003) Nature Structural Biology 10, 394-401 (PDB: 1NQE).
3. Pryor Jr., E. E. et al. (2013) Science 339, 1600-1604 (PDB: 4IL3).
4. Dawson, R. J., Locher, K. P. (2006) Nature 443, 180-185 (PDB: 2HYD).
5. Bertero, M. G. et al. (2003) Nature Structural Biology 10 681-687 (PDB: 1Q16).