Is CuII Coordinated to Patellamides inside Prochloron Cells?

5 years ago

Is CuII Coordinated to Patellamides inside Prochloron Cells?

Martin Seefeld, Gerhard Schenk, Geoffrey Nette, Annika Eisenschmidt, Dirk-Peter Herten, Lawrence R. Gahan, Peter Comba

Dinuclear CuII–patellamide complexes (patellamides are naturally occurring cyclic pseudo-octapeptides) are known to be efficient catalysts for hydrolysis reactions of biological importance, for example, those of phosphatase, carbonic anhydrase, and glycosidase. However, the biological role of patellamides is still unknown. Patellamides were originally extracted from the sea squirt Lissoclinum patella, but are now known to be ribosomally expressed by the blue-green algae Prochloron that live in symbiosis with L. patella. In a further step to unravel the metabolic significance of the patellamide complexes, the question as to whether these are also formed inside Prochloron cells is addressed. In this study, a biocompatible patellamide–fluorescent dye conjugate has been introduced into living Prochloron cells and, by means of flow cytometry and confocal microscopy, it is shown that CuII ions are coordinated to patellamides in vivo. CuII turns off the light: To prove the formation of a CuII–patellamide complex, a fluorescent-tag-labeled patellamide has been introduced into Prochloron to study its CuII-binding behavior (see figure).

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201700895