Nov 19 (Reuters) - Cyber-security company FireEye Inc said on Thursday it will receive a $400 million strategic investment from private equity firm Blackstone and venture capital firm ClearSky. Blackstone and ClearSky will purchase $400 million of FireEye’s convertible preferred stock, at a price of $1,000 per share. The preferred stock will be convertible into shares of FireEye’s common stock at $18.00 per share. Under the deal, FireEye will appoint Viral Patel, senior managing director at Blackstone, to its board. Separately, FireEye said it has bought Respond Software, a cyber-security investigation firm, in a cash-and-stock deal valued at $186 million. FireEye said it intends to use the proceeds from the Blackstone-led investment to support strategic growth initiatives, including the Respond acquisition. Shares of the FireEye were up nearly 10% in extended trading. (Reporting by Ayanti Bera in Bengaluru; Editing by Shailesh Kuber)