Mattress Source, an independent chain of more than a dozen stores in the Midwest, has filed for bankruptcy and will shutter some unprofitable locations, the St. Louis Post-Dispatch reported today. St. Louis-based Jamat LLC, which does business as the Mattress Source, filed for chapter 11 protection on Friday. It has 13 local stores in Missouri and Illinois. In its filing, the chain said that both its assets and estimated liabilities range between $1 million and $10 million.