The owners of Yum Yum Donut Shops have purchased the assets of East Coast Bagel, which include East Coast Bagel and Sonoma Valley Bagel cafes, according to an East Coast Bagel spokeswoman. Details of the transaction were not disclosed, though the spokeswoman said the acquisition price exceeded $2million. The new company will be called East Coast Sonoma and will consist of 23 cafes. East Coast Bagel filed for bankruptcy protection March 9 but continued to operate. The shops currently employ more than 276 people in California. Although Yum Yum owners Frank and Lincoln Watase have no plans to close any locations or terminate workers, they do expect to expand the menu in 1999, according to East Coast. The father-and-son owners will serve as co-chairmen of the new company. Currently, Santa Monica-based East Coast Bagel has stores in seven California counties, including five in Los Angeles, five in Orange and one in San Diego. Industry-based Yum Yum Donuts operates 75 shops in California. The sale is to be finalized this month. Both companies are privately held.