Intracellular crowding effects on the self-association of the bacterial cell division protein FtsZ

What Macromolecular Crowding Can Do to a Protein

“…Macromolecular crowding was shown to efficiently promote assembly of E. coli 60S ribosomal particles from the isolated 30S and 50S ribosomal subunits and increase a further interaction between 70S particles and form the 100S dimer [ 185 ]. Binding of hepatic aldolase B to the hepatocyte matrix [ 186 ], interaction of rat brain hexokinase with mitochondria from rat liver or yeast [ 187 , 188 ], self-assembly of the bacterial cell division protein FtsZ to dimers [ 189 ], long rod-like linear aggregates [ 190 ] and monomer-thick ribbons [ 191 ], formation of secretory granules, which are the storage place for many protein hormones [ 192 ], the self-assembly of capsid protein CA of human immunodeficiency virus type 1 (HIV-1) in vitro [ 193 ], the formation of a nucleoprotein complex between the bacterial virulence protein VirE2 and single stranded DNA (ssDNA) [ 194 ], binding of monomeric RepA protein encoded in the Pseudomonas pPS10 replicon to DNA [ 195 ], interaction between bovine milk xanthine oxidase and bovine erythrocyte copper, zinc-superoxide dismutase [ 196 ], self-association of polynucleosome chains [ 197 ], interaction of protein p6 from Bacillus subtilis phage phi29 with double-stranded DNA [ 198 ], binding of ligands to a receptor near membranes [ 199 ], formation of encounter complexes [ 200 ], formation of decamers of BPTI [ 201 ], homodimerization of apomyoglobin [ 202 ], polymerization of deoxyhemoglobin S [ 203 ], polymerization of actin [ 204 ], enhanced specific interaction between ubiquitin and UIM1 and between cytochrome c and cytochrome c peroxidase at the expense of nonspecific transient encounter complexes [ 205 ], as well as several other assembly-related processes were influenced by macromolecular crowding. However, high concentrations of PEG 600, PEG 1000, PEG 8000, and dextran 6 did not affect the formation of two high-affinity heterocomplexes (TEM1-β-lactamase with β-lactamase inhibitor protein (BLIP) and barnase with barstar) [ 206 ].…”

Liquid–Liquid Phase Separation of Peptide/Oligonucleotide Complexes in Crowded Macromolecular Media

“…As the cellular interior is a complicated crowding environment with the total concentration of biomolecules up to 400 mg/mL, the MLOs and the LLPS are inevitably affected by the environment via both excluded volume effect and nonspecific interactions. − Excluded volume effect is purely entropic origin, which generally promotes the combination of multimolecules and drives the reactions toward a volume-reduced direction. − Hancock reported that the nucleoli and PML bodies were disassembled when the cell nuclei expanded, while these compartments reassembled and the functions recovered as concentrated macromolecules such as PEG or dextran were presented, which could be reasonably explained by excluded volume effect . Banks et al studied the ensembles of FlgM, an intrinsically disordered protein (IDP), in polymer and protein solutions.…”

Computational Equilibrium Thermodynamic and Kinetic Analysis of K-Ras Dimerization through an Effector Binding Surface Suggests Limited Functional Role

“…12 The latter is presumably due to the increased effective local concentration and the reduced dimensionality of the search space for intermolecular encounter. In addition, intracellular salt and crowding conditions 44 likely have a significant effect on dimerization. Therefore, it is possible that the marginal solution stability of the β 2 dimer suggested by our calculations represents a lower limit of the actual affinity in the cell.…”