Threonine is an uncharged, polar amino acid whose three letter code is 'Thr' and single letter code is 'T'. It interacts with other polar molecules using hydrogen bonds. Its hydroxyl group is polar and its R group is uncharged and is C2H5O.
1. Lodish, H et al, 2008, Molecular Cell Biology, Sixth edition, 42-43, New York,NY:WH Freeman and Company.