Science funding agencies in the United States should make a broad push to improve the science of understanding sugars in order to enable widespread advances in medicine, energy, and materials. That’s the conclusion of a new report out today by the National Research Council of the U.S. National Academies.
The report’s authors, led by David Walt, a chemist at Tufts University in Medford, Massachusetts, note that the role of sugars in living organisms is widely underappreciated. They are the fourth major class of biological macromolecules, along with nucleic acids, proteins, and lipids. Sugar polymers, called glycans, are universal in living organisms, and play a role in virtually all major human diseases. The molecules are the primary component of plant cell walls, and as a result could serve as one of the biggest reservoirs for sopping up excess atmospheric carbon; they could also serve as a nonfossil source of fuel and novel materials.
The problem is that glycans are hard to study and manipulate in a systematic way. Unlike DNA and proteins, which can be sequenced and synthesized, that’s not an easy task with sugars. The difficulty lies in the way individual units connect together. In nucleic acids and proteins, the individual chemical units -- nucleotide bases in the case of DNA and RNA, and amino acids in the case of proteins -- are all linked by the same type of chemical bond. That’s not the case with glycans. Instead, a wide variety of individual sugar units are connected in multiple ways by a diverse family of enzymes. That makes for a wider diversity of sugar chains and increases the types of functional roles they play. “However, these characteristics also pose challenges to probing glycan structure and function and to being able to control and manipulate them in research,” the report concludes.