Lysine transporters in human trypanosomatid pathogens

INBARL E - CANEPA GE; CARRILLO C; GLASSERA F; SUTER-GROTEMEYERD M; RENTSCH D; ZILBERSTEIN D; PEREIRA CA

AMINO ACIDS

SPRINGER

Año: 2012 vol. 42 p. 347 - 360

0939-4451

In previous studies we characterized arginine transporter genes fromTrypanosoma cruzi and Leishmania donovani, the etiological agents of chagas diseaseand kala azar, respectively, both fatal diseases in humans. Unlike arginine transportersin higher eukaryotes that transport also lysine, these parasite transporters translocateonly arginine. This phenomenon prompted us to identify and characterize parasite lysinetransporters. Here we demonstrate that LdAAP7 and TcAAP7 encode lysine-specificpermeases in L. donovani and T. cruzi, respectively. These two lysine permeases areboth members of the large amino acid/auxin permease family and share certainbiochemical properties, such as specificity and Km. However, we evidence that LdAAP7and TcAAP7 differ in their regulation and localization, such differences likely a reflectionof the dissimilar L. donovani and T. cruzi life cycles. Failed attempts to delete bothalleles of LdAAP7 support the premise that this is an essential gene that encodes theonly lysine permeases expressed in L. donovani promastigotes and T. cruziepimastigotes, respectively.