(Reuters) - United States Trustee Tracy David filed a motion with a bankruptcy court late Sunday night seeking the appointment of a Chapter 11 trustee in the ongoing Dynegy Holdings bankruptcy proceeding. In her motion, David said, "The mismanagement of the debtors by their current management to the financial detriment of the debtors' creditors provides cause for the appointment of an independent fiduciary to manage the affairs of these debtors. ...