Barracuda Networks has acquired start-up Purewire in an effort to expand its footprint in the market for Web security services.Hottest tech M&A deals of 2009Launched last year, Purewire offers a managed security service to detect and block malware. Barracuda Networks, which offers content-security appliances to guard against threats involving e-mail, Web and instant messaging, says the acquisition of Purewire will allow it to expand into the Web security software-as-a-service (SaaS) market.Purewire\u2019s co-founders will assume management positions at Barracuda. Mike Van Bruinisse, Purewire\u2019s CEO, will join Barracuda as vice president of enterprise sales. CTO Paul Judge will become vice president of cloud services and chief research officer.Judge will be in charge of combining the Purewire and Barracuda Labs research teams to identify and track threats, says Dean Drako, president and CEO of Barracuda, based in Campbell, Calif. Current plans call for Purewire to remain in Atlanta.\u201cWe have need for more senior management,\u201d Drako says, adding that Purewire\u2019s co-founders have done a great job developing a new platform at the start-up and have considerable industry experience.\u201cUnder their leadership, Purewire has helped to shape the Web security SaaS market in a very short period of time,\u201d Drako says.Today about 85,000 organizations make use of Barracuda\u2019s security products. Some customers deploy the appliances on their own, and others opt to use them in conjunction with cloud-based services, including backup services. The addition of Purewire promises to expand Barracuda\u2019s services portfolio. Drako also notes that the Purewire service should benefit from Barracuda\u2019s extensive sales and marketing group.The companies did not disclose the value of the deal.