A Deutsche Bank AG unit was sued by a trustee for mortgage-bond investors over $183 million in defective loans backing the securities, Bloomberg News reported yesterday. DB Structured Products breached promises about the quality of the loans that were pooled and packaged into securities, trustee HSBC Bank said in a court filing yesterday in New York State Supreme Court in Manhattan. A review of loans indicate problems "may be pervasive and systemic across the loan portfolio," HSBC said. The bank seeks an order requiring DB Structured Products to repurchase loans, according to the filing.