Magic-angle spinning (31)P NMR spectroscopy of condensed phosphates in parasitic protozoa: visualizing the invisible.
We report the results of a solid-state (31)P nuclear magnetic resonance (NMR) spectroscopic investigation of the acidocalcisome organelles from Trypanosoma brucei (bloodstream form), Trypanosoma cruzi and Leishmania major (insect forms). The spectra are characterized by a broad envelope of spinning sidebands having isotropic chemical shifts at approximately 0, -7 and -21 ppm. These resonances are assigned to orthophosphate, terminal (alpha) phosphates of polyphosphates and bridging (beta) phosphates of polyphosphates, respectively. The average polyphosphate chain length is approximately 3.3 phosphates. Similar results were obtained with whole L. major promastigotes. (31)P NMR spectra of living L. major promastigotes recorded under conventional solution NMR conditions had spectral intensities reduced with respect to solution-state NMR spectra of acid extracts, consistent with the invisibility of the solid-state phosphates. These results show that all three parasites contain large stores of condensed phosphates which can be visualized by using magic-angle spinning NMR techniques.
Departments of Chemistry and Biophysics, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA.
Benjamin
B
Moreno
Claudia O
CO
Rodrigues
Brian N
BN
Bailey
Julio A
JA
Urbina
Silvia N J
SN
Moreno
Roberto
R
Docampo
Eric
E
Oldfield
D000818:Animals; D018320:Leishmania major / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015388:Organelles / Q000737:chemistry; D010759:Phosphorus Isotopes; D011122:Polyphosphates / Q000032:analysis*; D014346:Trypanosoma brucei brucei / Q000737:chemistry*; D014349:Trypanosoma cruzi / Q000737:chemistry*
D010759:Phosphorus Isotopes; D011122:Polyphosphates