Turkish energy firm Energy Exchange Istanbul (EXIST) held onto the top spot on Fortune magazine’s top 500 Turkish companies list in terms of net sales. EXIST's sales last year totaled 839 billion Turkish liras ($36.1 billion), up 4.9% at an annualized pace, according to a statement issued by the magazine on Monday. Energy firm TUPRAS, also keeping its place at number two on the list, saw 686.5 billion liras ($29.6 ...