Inhibitors of PEX14 disrupt protein import into glycosomes and kill Trypanosoma parasites

The parasitic protists of the Trypanosoma genus infect humans and domestic mammals, causing severe mortality and huge economic losses. The most threatening trypanosomiasis is Chagas disease, affecting up to 12 million people in the Americas. We report a way to selectively kill Trypanosoma by blocking glycosomal/peroxisomal import that depends on the PEX14-PEX5 protein-protein interaction. We developed small molecules that efficiently disrupt the PEX14-PEX5 interaction. This results in mislocalization of glycosomal enzymes, causing metabolic catastrophe, and it kills the parasite. High-resolution x-ray structures and nuclear magnetic resonance data enabled the efficient design of inhibitors with trypanocidal activities comparable to approved medications. These results identify PEX14 as an "Achilles' heel" of the Trypanosoma suitable for the development of new therapies against trypanosomiases and provide the structural basis for their development.

Über Reaktionen organischer Radikale mit Palladium- und Platinkomplexen / Reactions of Organic Radicals with Palladium and Platinum Complexes

Preparation, IR- and EPR-spectra of paramagnetic dichloro-porphyrexid-palladium(II) from porphyrexid and sodium-tetrachloropalladate are reported.

The reaction of organic radicals with tetrakis (triphenylphosphine) platinum (O) provides a new type of oxydative addition. Treatment of Pt (PPh3)4 with 1,2-diphenyl-2-picrylhydrazyl yielded diphenylamido-2,4,6-trinitrophenyl-bis (triphenylphosphine) platinum (II). Dibenzoylperoxide yielded cis-dibenzoato-bis (triphenylphosphine) platinum (II), whereas with diaryl- and dialkylnitrogenoxide and tetraarylhydrazine no reaction was observed.