US STOCKS-Wall St notches fourth straight advance as energy gains

Wall Street gained for a fourth straight session on Tuesday, its longest winning streak since January, buoyed by the energy sector as oil prices rebounded from early declines. Oil prices were initially lower on concerns a deal between Iran and six global powers would result in more supply, but turned higher after it became apparent sanctions on Tehran's crude exports would not be removed immediately. The S&P energy sector advanced 0.8 percent, led by a 0.8 percent gain in Exxon Mobil Corp to $83