Chicago private equity firm GTCR has purchased Vocus Inc.

Vocus, headquartered in Beltsville, Md., provides cloud-based public relations and marketing software. The software automates and integrates communications functions to help organizations manage relationships with reporters and the public. The purchase price is about $447 million. The deal was announced on May 30.

GTCR plans to combine Vocus with Cision, another provider of cloud-based public relations software in which the firm bought a majority stake in April. Combined, the business should offer new software tools, content and services to clients. 

GTCR was named Mergers & Acquisitions Private Equity Firm of the Year for 2013. GTCR managing director Phil Canfield (pictured) said in March that the firm has grown "modestly and sustainably." In March, the firm's portfolio company, Sterigenics, made a $727 million deal for Noridion Inc., which provides services to the health science market. In February, the firm bought Callcredit, which provides consumer credit data services, software and analytics. 

Deutsche Bank Securities Inc. is acting as financial adviser to GTCR, while Latham & Watkins provided legal advice. Stifel is Vocus' financial adviser, while Skadden Arps Slate Meagher & Flom acted as legal counsel.