2OO9 – 2O1O - Faculty of Dentistry - University of Otago

NICHOLAS HENG
BSc (Hons) PhD (Otago)
Oral Sciences
Senior Lecturer
Dr Heng’s primary research expertise is in the field of
molecular microbiology specialising in bacterial genetics
and gene expression networks/pathways. His current
research activities include whole genome sequencing
(oral bacteria), oral metagenomics (characterisation of
the microbial composition from the oral cavity), and
bioinformatics, all in relation to oral biology.
Research and Collaboration
The scope of research conducted by Dr Heng’s group
during 2009-2010 included:
(1) Microbial (bacterial) diversity of the human oral cavity
in health and disease (periodontal disease and dental
caries) using the GS-FLX Titanium high-throughput
DNA sequencing system;
(2) Completing the genome of Streptococcus salivarius,
one of the more prominent bacterial species
inhabiting the oral cavity. The group wishes to reveal
the genetic secrets that allow S. salivarius to be such a
successful oral coloniser; and
(3) Characterisation of potential mutations conferring
triclosan resistance in oral bacteria.
Within the Faculty of Dentistry, he currently has ongoing
collaborations with Professor G.J. Seymour and Associate
Professor M.P. Cullinan (Discipline of Periodontics), and
Associate Professor B.K. Drummond (Discipline of
Paediatric Dentistry) in relation to the metagenomic
projects. In addition, he collaborates with Professor J.R.
Tagg (Department of Microbiology & Immunology, Otago
School of Medical Sciences) in the field of bacteriallyderived
antimicrobial proteins (bacteriocins), focusing
on the genetic aspects. Among the aims of the genome
sequencing projects are: (a) uncovering new antimicrobial
proteins produced by S. salivarius which could be useful in
the development of new oral probiotic preparations and
(b) determining whether there are any virulence factors
encoded by the genomes, in order to verify the “safety” of
the species for use as probiotics. The triclosan resistance
project is an ongoing international collaboration with Dr
P.S. Bird (University of Queensland, Australia).
32 FACULTY OF DENTISTRY RESEARCH REPORT 2009-2010
Recent Publications
Seymour GJ, Cullinan MP, Heng NCK. Methods in Molecular
Biology, Vol. 666: Molecular techniques and applications in
oral biology. Humana Press, U.S.A. (2010).
Heng NCK, Stanton JL. Oral bacterial genome sequencing
using the high-throughput Roche Genome Sequencer
FLX system, pp.197-218, In G.J. Seymour, M.P. Cullinan
and N.C.K. Heng (eds.), Methods in Molecular Biology, Vol.
666: Molecular techniques and applications in oral biology.
Humana Press, U.S.A. (2010).
Swe PM, Heng NCK, Cook GM, Tagg JR, Jack RW.
Identification of DysI, the immunity factor of the
streptococcal bacteriocin dysgalacticin. Applied and
Environmental Microbiology 76: 7885-7889 (2010).
Wescombe PA, Heng NCK, Burton JP, Tagg JR. Something old
and something new: an update on the amazing repertoire of
bacteriocins produced by Streptococcus salivarius. Probiotics
and Antimicrobial Proteins 2: 37-45 (2010).