Assignment of phycocyanobilin in HMPT using triple resonance experiments

Magn Reson Chem. 2011 Sep;49(9):543-8. doi: 10.1002/mrc.2776. Epub 2011 Aug 4.

Abstract

A complete assignment of all resonances of a small organic molecule is a prerequisite for a structure determination using NMR spectroscopy. This is conventionally obtained using a well-established strategy based on COSY, HMQC and HMBC spectra. In case of phycocyanobilin (PCB) in HMPT this strategy was unsuccessful due to the symmetry of the molecule and extreme signal overlap. Since (13)C and (15)N labeled material was available, an alternative strategy for resonance assignment was used. Triple resonance experiments derived from experiments conventionally performed for proteins are sensitive and easy to analyze. Their application led to a complete and unambiguous assignment using three types of experiments.

Keywords: assignment; phycocyanobilin; triple resonance experiments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon Isotopes
  • Hempa / chemistry
  • Magnetic Resonance Spectroscopy / methods*
  • Molecular Structure
  • Nitrogen Isotopes
  • Phycobilins / chemistry*
  • Phycobilins / isolation & purification
  • Phycocyanin / chemistry*
  • Phycocyanin / isolation & purification
  • Spirulina / chemistry
  • Tetrapyrroles / chemistry*
  • Tetrapyrroles / isolation & purification

Substances

  • Carbon Isotopes
  • Nitrogen Isotopes
  • Phycobilins
  • Tetrapyrroles
  • Phycocyanin
  • phycocyanobilin
  • Hempa