Iodotyrosine deiodinase: a unique flavoprotein present in organisms of diverse phylaElectronic supplementary information (ESI) available: NCBI accession numbers for IYD homologs chosen for expression; optimized conditions for expressing IYD homologs; SDS-PAGE gel images of purified IYD homologs; identification of active IYD from hydra (hmIYD); deiodination rate dependence on DIT concentration for IYD homologs. See DOI: 10.1039/c3mb70398c
Royal Society of Chemistry Gold Collection excluding archive 2021 New Customers
Iodide is required for thyroid hormone synthesis in mammals and other vertebrates. The role of both iodide and iodinated tyrosine derivatives is currently unknown in lower organisms, yet the presence of a key enzyme in iodide conservation, iodotyrosine deiodinase (IYD), is suggested by genomic data from a wide range of multicellular organisms as well as some bacteria. A representative set of these genes has now been expressed, and the resulting enzymes all catalyze reductive deiodination of diiodotyrosine with
values within a single order of magnitude. This implies a physiological presence of iodotyrosines (or related halotyrosines) and a physiological role for their turnover. At least for Metazoa, IYD should provide a new marker for tracing the evolutionary development of iodinated amino acids as regulatory signals through the tree of life.
Pervasive distribution of a reductive deiodinase originally associated with thyroid function.