Dr Wilford Lie

Research Interests

Nuclear magnetic resonance spectroscopy

Nuclear magnetic resonance spectroscopy (NMR) has been widely used as one of the most powerful instrumental techniques available for studying molecular structure and molecular dynamic. It relies on magnetic properties possessed by many species of nuclei.

An NMR signal arises from a nuclear property called spin, which is a quantum phenomenon whenever an external magnetic field is present. A model of it imagines a spin being a dipole spinning with its axis sweeping on a conical surface like a tilting top. All nuclear spins are quantised at equilibrium; many of them have only two spinning status, either up or down, notably those of 1H, 13C, 15N, 19F and 31P.

Any locally bonded nuclei and other moving charges surrounding a nuclear generate a local magnetic field, thereby changing slightly the spinning frequency of the nuclear simply because of the difference in chemical environment. This often allows us to identify the nuclear from their distinctively frequency, which is usually converted into a dimensionless quantity called chemical shift in NMR spectra.

Furthermore, nuclear spins can be manipulated by different sequences of pulses to produce different types of NMR spectra in different dimensions, giving us useful structural information of different aspects, including the connections and distances between neighbouring nuclei, etc.

Particular areas of research interest are:

Bio-molecular NMR

The applications of multi-dimensional NMR spectroscopy have been developed rapidly since 2D NMR spectroscopy was proposed [Jeener 1971] and materialised [Ernst 1974, 1975, 1976]. With its fascinating potential to study molecular conformation and the ease of applications using commercially available high-resolution NMR spectrometers, NMR spectroscopy has become one of the most rapidly developed and widely used tools in bio-molecular research. This is marked by an upsurge of multi-dimensional NMR experimental methods, resulting in thousands of NMR-related papers being published in the last few decades. Many of the published evidences have unequivocally proved that NMR spectroscopy is a powerful tool for investigating 3D molecular structure of proteins in solution, which in many cases is complementary to X-ray crystallography. Research on protein folding, protein stability, as well as interactions between protein-chemical, protein-protein, protein-DNA and protein-RNA has also been conducted using NMR spectroscopy. These applications have opened a new era to reason some important properties of bio-molecules at 3D molecular level, such as biological functions of bio-molecules, disease mechanism, and drug designs.

NMR in medical applications

The applications of NMR spectroscopy in medicine have been widely seen as MRI, the magnetic resonance imaging. However, at the molecular level, little has been achieved in routine applications of NMR spectroscopy in solution, although it is potentially attractive. For example, the detection of phospholipids using 31P NMR has shown significant achievement recently in biological applications, which is one of the many areas we can expect to achieve excellent results in our lab.

Representative Publications

Phytochemical studies on Stemona plants: isolation of new tuberostemonine and stemofoline alkaloids. Sastraruji, Thanapat; Jatisatienr, Araya; Issakul, Kritchaya; Pyne, Stephen G.; Ung, Alison T.; Lie, Wilford; Williams, Morwenna C. Natural Product Communications (2006), 1(10), 813-818.

Confirmation of the structure of oxystemokerrin by single crystal X-ray structural analysis and a proposed biosynthesis.Mungkornasawakul, Pitchaya; Matthews, Hayden; Ung, Alison T.; Pyne, Stephen G.; Jatisatienr, Araya; Lie, Wilford; Skelton, Brian W.; White, Allan H. ACGC Chemical Research Communications (2005), 1930-33.

Caerin 4.1, an antibiotic peptide from the Australian tree frog, Litoria caerulea. The NMR-derived solution structure.Chia, Brian C. S.; Carver, John A.; Lindner, Robyn A.; Bowie, John H.; Wong, Herbert; Lie, Wilford. Australian Journal of Chemistry (2000), 53(4), 257-265.

Abbreviated CV

2000-2002: Post-doctoral fellow in Medical Research Centre, University of Canterbury, New Zealand.

2002-2008: NMR Facility Manager, School of Chemistry, University of Wollongong.

2003- 2008 Lecturer for NMR Spectroscopy at School of Chemistry, University of Wollongong, Australia.