BEIJING, July 10 (Xinhuanet) -- Google said on Monday it would pay 625 million U.S. dollars to buy the online security firm Postini to target large businesses of online security services.

The purchase is expected to close by the end of September.

Postini, an online security firm, specializes in providing Web-hosted security solutions, mostly for email and instant messaging applications.

With Postini's security, Google can beef up its business services such as e-mail, instant messaging, online calendar services and online productivity software.

"We are fundamentally here today because we believe that this is a business that Google should be in," said Dave Girouard, vice president and general manager of Google Enterprise during a conference call.

Google has acquired YouTube for a little more than twice Postini's sticker price and has been in the process of buying Doubleclick roughly five times more than it is spending on Monday morning's deal.

(Agencies)