Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Ubiquitin-like modifier-activating enzyme 6 is a protein that in humans is encoded by the UBA6 gene. Proteins (also known as polypeptides) are organic compounds made of amino acids arranged in a linear chain and folded into a globular form. The amino acids in a polymer are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues. The sequence of amino acids in a protein is defined by the sequence of a gene, which is encoded in the genetic code.