WASHINGTON (AP) — The top GOP aide to a House committee investigating Solyndra Inc. once worked for a lobbying firm that helped the now-bankrupt solar company apply for a half-billion-dollar federal loan.Gary Andres, staff director of the House Energy and Commerce Committee, was a vice chairman at Dutko Worldwide until last December, when he was appointed to his current post by GOP Rep. Fred Upton of Michigan, chairman of the energy panel. The committee is investigating Solyndra, which received a $528 million Energy Department loan in 2009. The company later went bankrupt and laid off 1,100 workers.The Kalamazoo Gazette reported Monday that Solyndra paid Dutko $30,000 in 2008 to handle its application for the federal loan. Alexa Marrero, a spokeswoman for the committee, said Andres never worked on behalf of Solyndra.