The repressor is a dimer of a 236 amino acid subunit. Each subunit consists of two domains, one of which (the N-terminal) includes the helix-turn-helix motif and binds DNA, while the other is responsible for the formation of dimers. However, the two domains of one subunit can be separated by mild proteolysis.
The purpose of a marriage license is to provide proof that a couple is allowed to enter into a legally recognized marriage. In order to receive a marriage license, couples must provide proof of their eligibility of meeting all state requirements.
But a handful of states still require a blood test for a marriage license. Those states are District of Columbia, Mississippi, Montana (female) . In those states, the county clerk will NOT issue you a marriage license without a blood test. You can get the blood test from any doctor or walk-in clinic.