Some selenium donor proteins (selenide,water dikase, product of the selD gene, model TIGR00476) are fusion proteins with an N-terminal extension described by model TIGR03169. Members of this family have a C-terminal region similar to yet outside the scope of the SelD model, fused to an N-terminal region similar to but outside the scope of TIGR03169.
Jiyao W et al.(2023). "The conserved domain database in 2023.",