Circular clamps are utilised by replicative polymerases to enhance processivity. The topological problem of loading a toroidal clamp onto DNA is overcome by ATP-dependent clamp loader complexes. Different organisms use related protein machines to load clamps, but the mechanisms by which they utilise ATP are surprisingly different. Using mutant clamp loaders that are deficient in either ATP bind...

As a product of protein catabolism, urea is moved around the body and through kidneys for excretion. Although there experimental evidence concentrative transporters, these have not been defined at molecular level. The SLC14 family are facilitative allowing movement down its concentration gradient. Multiple splice variants transporters identified; UT-A in particular, cell-specific expression wit...