“…Studies in this field revealed that the efficiency of crowding agents might depend on the ratio between the hydrodynamic dimensions (or occupied volumes) of the crowder and the test molecule, with the most effective conditions being those where the crowder and the test molecule occupy similar volumes ( Chen et al, 2011 ; Minton, 1993 ; Tokuriki et al, 2004 ). Typically, high concentrations of inert crowders have significant effects on conformational stability and structural properties of some proteins ( Christiansen et al, 2010 ; Engel et al, 2008 ; Kuznetsova, Turoverov & Uversky, 2014 ; Mittal & Singh, 2013 ), and may affect various biological processes, such as protein folding, binding of small molecules, enzymatic activity, protein-nucleic acid interactions, protein-protein interactions, protein chaperone activity, pathological protein aggregation, and extent of amyloid formation ( Chebotareva et al, 2015a ; Chebotareva, Filippov & Kurganov, 2015b ; Hatters, Minton & Howlett, 2002 ; Kuznetsova, Turoverov & Uversky, 2014 ; Kuznetsova et al, 2015 ; Minton, 2000a ; Morar et al, 2001 ; Shtilerman, Ding & Lansbury, 2002 ; Uversky et al, 2002 ). For example, we recently conducted a large-scale analysis of the effect of two traditional macromolecular crowders, PEG-8000 and Dextran-70, on the urea-induced unfolding of eleven globular proteins belonging to different structural classes ( Stepanenko et al, 2016a ).…”