T he proteoglycan bikunin has a defined sequence

This paper shows that proteoglycans are likely composed of specific sequences of glycans by sequencing the proteoglycan bikunin. To sequence bikunin, tandem MS was used in addition to PAGE gels. The authors discovered that odd numbered chains exist in greater abundance and a sulfated and non-sulfated sequence exist within the bikunin sequence. I thought this was an interesting paper because previously proteoglycan sequences were thought to be random, which rarely occurs in biological systems. Ly et al. provide evidence that this is probably not the case and that proteoglycans likely have a defined sequence.