Worldpay suffers reversal of fortune
Shares in Worldpay slumped 8.8% after news broke that it was being taken over by US rival Vantiv.
Earlier in the day, the company had been leading the FTSE 100 for the second day running, following a rise of 25% on Tuesday.
Tesco was the biggest riser, up 3.8% after wholesaler Booker reported strong sales figures. Tesco's deal to buy Booker awaits approval from regulators.
Overall, the FTSE 100 closed up 10.37 points or 0.14% at 7,367.60.
Housebuilder Persimmon rose 2.4% on the strength of solid first-half results.
The company said sales rose by 7% year-on-year in the period, unaffected by general election jitters.
Persimmon's performance lifted the sector, with rivals Barratt and Taylor Wimpey also trading higher.
On the currency markets, the pound was up 0.11% against the dollar at $1.2933 and also up 0.11% against the euro at 1.1399 euros.