German TV operator ProSiebenSat.1 (FRA: PSM) has bought 25.1 percent of AutoPlenum.de, a car portal launched last year by publisher Holtzbrinck’s eLab and founder Malte Krüger. The acquisition price wasn’t disclosed but ProSiebenSat.1 has secured an option to take a 50.1 percent majority stake later on. AutoPlenum.de comprises editorial erviews and reports from a range of sources as well as user-contributed reports and car reviews.