Ion specific effects on aqueous phase separation of responsive copolymers for sustainable membranes.

Hypothesis: Salt identity and concentration affects the preparation of membranes via the aqueous phase separation approach. The phase inversion process and morphology of the resultant membranes is expected to vary as function of these two parameters.

Experiments: Polymeric membranes based on the responsive copolymer polystyrene-alt-maleic acid (PSaMA) are prepared using the aqueous phase separation approach and the influence of salt identity (NaSO, LiCl, NaCl, NaNO, NHCl, MgCl, CaCl) and concentration on resultant membrane morphology and separation performance is investigated.

Real-time analysis of RAG complex activity in V(D)J recombination.

Single-molecule FRET (smFRET) and single-molecule colocalization (smCL) assays have allowed us to observe the recombination-activating gene (RAG) complex reaction mechanism in real time. Our smFRET data have revealed distinct bending modes at recombination signal sequence (RSS)-conserved regions before nicking and synapsis. We show that high mobility group box 1 (HMGB1) acts as a cofactor in stabilizing conformational changes at the 12RSS heptamer and increasing RAG1/2 binding affinity for 23RSS.