No abstract

No abstract

Think zinc: We have developed a new preparation method for generating the apo‐enzyme of IMP‐1 metallo‐β‐lactamase (apo‐IMP‐1) with the combination of a chelating agent (EDTA) and desalting column chromatography. An advantage of this method is that enzymatic activity of the apo‐enzyme comparable to that observed with the native enzyme could be restored upon addition of ZnII ions (see scheme).

A calix[4]arene carboxylate resin was prepared by calix[4]arene carboxylate on polymer matrices of polyallylamine to investigate the resin's adsorption behavior for some metal ions including lead ion. The selectivity sequence among the base metal ions on the resin is as follows:Pb bb Cu bb Zn 6 Ni 6 CoThe origin of the selectivity sequence is attributed not to amino groups of the polymer matrices but to the functional groups of calix[4]arene carboxylate introduced. Although maximum loading capacity for lead ion on the resin was not very high, it shows high lead selectivity and the separation of trace amount of lead from large excess of zinc was completely achieved.

No abstract