Reentrant condensation of proteins in solution induced by multivalent counterions.
Negatively charged globular proteins in solution undergo a condensation upon adding trivalent counterions between two critical concentrations C and C, C <C. This reentrant condensation behavior above C is caused by short-ranged electrostatic interactions between multivalent cations and acidic residues, mechanistically different from the case of DNA. Small-angle x-ray scattering indicates a short-ranged attraction between counterion-bound proteins near C and C. Monte Carlo simulations (under these strong electrostatic coupling conditions) support an effective inversion of charge on surface side chains through binding of the multivalent counterions.
Zhang
F
F
Institut für Angewandte Physik, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
Skoda
M W A
MW
Jacobs
R M J
RM
Zorn
S
S
Martin
R A
RA
Martin
C M
CM
Clark
G F
GF
Weggler
S
S
Hildebrandt
A
A
Kohlbacher
O
O
Schreiber
F
F
D002412:Cations / Q000737:chemistry; D003198:Computer Simulation; D007811:Lanthanum / Q000737:chemistry; D008956:Models, Chemical; D009010:Monte Carlo Method; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D053838:Scattering, Small Angle; D012996:Solutions; D055672:Static Electricity; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry*
D002412:Cations; D011506:Proteins; D012996:Solutions; C028521:lanthanum chloride; D014867:Water; C064782:yttrium chloride; D015019:Yttrium; D007811:Lanthanum