These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Multiple conformations of the metal-bound pyoverdine PvdI, a siderophore of Pseudomonas aeruginosa: a nuclear magnetic resonance study. Author: Wasielewski E, Tzou DL, Dillmann B, Czaplicki J, Abdallah MA, Atkinson RA, Kieffer B. Journal: Biochemistry; 2008 Mar 18; 47(11):3397-406. PubMed ID: 18298082. Abstract: Under iron-deficient conditions, the Gram-negative bacterium Pseudomonas aeruginosa ATCC 15692 secretes a peptidic siderophore, pyoverdine PvdI, composed of an aromatic chromophore derived from 2,3-diamino-6,7-dihydroxyquinoline and a partially cyclized octapeptide, d-Ser- l-Arg- d-Ser- l-FoOHOrn-( l-Lys- l-FoOHOrn- l-Thr- l-Thr), in which the C-terminal carboxyl group forms a peptidic bond with the primary amine of the l-Lys side chain. In aqueous solution at room temperature, the (1)H NMR spectrum of pyoverdine PvdI-Ga(III) showed clear evidence of exchange broadening. At 253 K, two distinct conformations were observed and the measurement of structural constraints was possible. The three-dimensional structures of the two PvdI-Ga(III) conformers were determined, and analysis of the structures indicates that the observed conformational exchange involves a stereoisomerization of the metal binding coordination accompanied by a change in the global shape of the siderophore. This conformational transition was further characterized by heteronuclear relaxation experiments. The possible implications of this dynamic behavior for siderophore recognition by the receptor FpvAI are discussed.[Abstract] [Full Text] [Related] [New Search]