Kolusheva et al. describe a colorimetric assay for identifying peptides with antimicrobial activity (see p. 225). They found that assemblies of phospholipids and polymerized polydiacetylene would change colors quite strikingly upon interacting with certain peptides. The ability of these peptides to produce the structural perturbations that led to the color change correlated with their antimicrobial activity, providing a more rapid way of screening peptides for this activity.

Oocyte enucleation is a critical parameter affecting the efficiency of cloning by nuclear transfer. It is currently performed by aspirating the cytoplasm just below the first polar body, followed by Hoechst staining to confirm the removal of DNA. In this issue, Keefe and colleagues describe a noninvasive technique for spindle imaging and oocyte enucleation using a new microscope, termed the Pol-Scope (p. 223). They show that they can achieve an enucleation efficiency of 100%, and that the reconstituted rodent oocytes develop normally.