sentence: In addition to well-documented substrates , we searched for candidate CK2 substrates based on the presence of the CK2 consensus sequence [ 16 ] , the enzyme – substrate predictions retrieved from NetworKIN database [ 54 ] , the dataset of high confidence CK2 substrates reported by Bian et al. [ 55 ] , and the phosphoproteins that interact with protein kinase CK2 according to the Metascape database [ 56 ] .