Authorities said on Saturday decision was taken in order to recover multi-billion dollar debts owed by the clan in the wake of a major bank scandal.
The Savings and Deposits Insurance Fund did not say how many companies it was taking over. Anatolia news agency quoted a senior official as saying about 200 institutions were seized.
The Fund said the Uzans had failed to repay 7.5 thousand billion Turkish lira ($5.6 billion) to authorities after the seizure of their flagship bank Imar last year for large-scale fraud.
A subsequent investigation into the bank revealed a huge deficit, establishing also that the company hid the real number of its clients and sold non-existing treasury bonds.
The government has drawn up a plan to reimburse the bank's
The Fund said the Uzans failed to present any plan on how they would now repay their debt to authorities and shied away from any talks on the issue.
The Uzans' interests range from media to telecommunication and construction materials.