Glycobiology - the study of carbohydrates in biology - combines
expertise in synthetic and analytical chemistry and carbohydrate
biochemistry, as well as molecular and cellular biology, to unravel the
structural complexity, chemistry, biosynthesis, and biological
functions of sugar-bearing biomolecules. Over the past three decades,
complex carbohydrates have become widely recognized as more than just
an energy source .
Indeed, glycosylation has been established as a ubiquitous
post-translational modification in higher organisms that enables one
protein (or lipid) to function as many, and provides structural
diversity that offers an explanation for the unexpectedly low number of
genes in the human genome .
Complex sugars are major players in numerous biological processes,
including developmental biology, the immune response and inflammatory
disease, cell proliferation and apoptosis, the pathogenesis of
infectious agents including prions, viruses, and bacteria, and a wide
range of diseases ranging from rare congenital disorders to diabetes
The incredible complexity of a cell's glycosylation machinery and its final products, a vast array of oligosaccharides (Figure 1),
provides a research challenge in urgent need of high-throughput,
large-scale technologies. Unfortunately, methods for studying and
manipulating complex carbohydrates lag behind the tremendous advances
made for nucleic acids and proteins .
Progress has been sluggish, in part because many biologists were slow
to recognize the importance of sugars. But even when prescient
researchers sought to uncover the role of glycosylation they were often
frustrated by the difficulty of characterizing carbohydrates and the
near impossibility of manipulating them with precision in living cells.
In this article, we give a brief overview of the overriding factor
hindering glycobiology - the incredible complexity of carbohydrates -
before describing current technologies available for studying
glycosylation and concluding with a guarded, but optimistic, prediction
that glycobiology will catch up with other areas of biochemistry and
molecular biology largely by virtue of promising large-scale
technologies that are now on the horizon.