3'-iodo-L-thyronine + iodide + A + H(+) <=> 3',5'-diiodo-L-thyronine + AH2
3'-iodo-l-thyronine + iodide + a + h(+) <=> 3',5'-diiodo-l-thyronine + ah2
3'-iodo-L-thyronine + iodide + A + H(+) <=> 3',5'-diiodo-L-thyronine + AH2
3'-iodo-l-thyronine + iodide + a + h(+) <=> 3',5'-diiodo-l-thyronine + ah2