Athens, Ga. If genes provide the blueprint for life and proteins are the machines that do much of the work for cells, then carbohydrates that are linked to proteins are among the tools that enable cells to communicate with the outside world and each other. But until now, scientists have been unable to determine the structure of a biologically important so-called GAG proteoglycanor even to agree whether these remarkably complex molecules have well-defined structures.
In a paper published in the early online edition of the journal Nature Chemical Biology, however, a team of scientists from the University of Georgia and Rensselaer Polytechnic Institute announced that it has, for the first time, determined the sequence and structure of a glycosaminoglycan, or GAG, proteoglycan.
"The fact that a structure even exists is surprising, because people had the sense that the complexity of these molecules pointed to a randomness," said study co-author Jonathan Amster, professor and head of the department of chemistry in the UGA Franklin College of Arts and Sciences. "There are many different areas in medicine that will be enabled by understanding carbohydrates at this fundamental level."
Modifications to the GAG, or carbohydrate biopolymer, portion of proteoglycans have been associated with the presence and malignancy of certain cancers, for example, and the researchers noted that the identification of carbohydrates that are involved in disease opens the door to the development of drugs that can block their action.
The field of glycobiology is still in its infancy, largely because attempts to sequence proteoglycans have, until now, ended in frustration and failure. A small sample of DNA can be amplified many times, and its sequence, or arrangement of molecules, can be determined quickly with modern tools. DNA is simply a set of instructions for making proteins, so a sample of DNA also can allow scientists to produce copious qua
|Contact: Sam Fahmy|
University of Georgia