Continuing our research on the development of nucleopeptides as ODN analogs for biomedical and bioengineering applications, here we report the synthesis and the chemical physical characterization of a homoadenine hexamer based on a l-diaminobutyric acid (l-DABA) backbone (dabPNA), and its binding studies with a complementary aegPNA.
Direct binding studies with a recombinant receptor binding fragment (RBF) from rat alpha1M and murine macrophages demonstrate two classes of binding sites of apparent Kd = 90 pM (1500 sites/cell) and 40 nM (60,400 sites/cell).
The subsequent binding studies with the lectin Con A revealed a clear trend that binding affinity increases with increasing sugar content and a minimum of 10% of d-mannosylated chains is required for an effective and detectible aggregation.
This is consistent with plasma binding studies with m-THPC that shows an unusual initial protein-binding pattern for a hydrophobic photosensitiser (Hopkinson et al, 1999).
Stability and competitive binding studies with Cu- 5 were performed using an excess of CuSO4, ascorbic acid, or EDTA.
In addition, SR-A is mostly intracellular (21), rendering binding studies with whole cells suboptimal, while lysis increases receptor availability by releasing this intracellular receptor pool.
Binding studies with nucleosomes modified with K36Cme3 revealed that a basic surface on the PWWP domain reinforces K36me3 engagement.
Previous binding studies with the resistant line employed here, showed a 5-fold decrease in the binding affinity of Cry1Ca toxin to brush border membrane vesicles prepared with midguts from the resistant line.
The immunoreactivity of the PEGylated enzyme was compared to a wild type control using in vitro binding studies with both enzyme-specific antibodies, from immunized New Zealand white rabbits, and a single chain antibody library, derived from a human volunteer.
Consistently, binding studies with purified mutant LacY molecules show that of a dozen replacements for Asn272 only mutant N272Q binds NPG with an affinity similar to that of the WT.
