Image courtesy of BioMed Realty

BioMed Realty is joining the procession of life science developers to Boston’s Seaport District with the acquisition of the former John Hancock headquarters at 601 Congress St.

The San Diego life science specialist said it’s converting the 482,000-square-foot office building, which was originally completed in 2004, into lab-ready space available in the second half of 2022.

“We see the Seaport as an area that’s going to interact very well with our Boston-Cambridge footprint. We’re 100 percent leased for the Cambridge portfolio, so we’re really in need of space to grow,” said Colleen O’Connor, vice president of leasing for BioMed Realty.

The ground lease which expires in 2096 was transferred from John Hancock Real Estate for $362 million, according to a Suffolk County Registry of Deeds filing. The parcel is owned by Massport.

BioMed plans to convert the second through 12th floors of the building into a 50-50 split of office and lab space, O’Connor said, while retaining offices on the 13th and 14th floors. The building’s robust mechanicals and utility capacity made it suitable for a lab conversion, BioMed said.

The transaction follows BioMed’s blockbuster December acquisition of a 2.3 million-square-foot life science portfolio in East Cambridge for $3.45 billion. The transaction was the biggest-ticket real estate deal in the U.S. since November 2019, according to research by brokerage Avison Young.

BioMed also completed its $93.7 million acquisition on Dec. 23 of a life science development site on Middlesex Avenue in Somerville, where it’s planning 1.6 million square feet of commercial space.

601 Congress St. has been available since 2018, when John Hancock opted to consolidate its office space in Back Bay at 200 Berkeley St. and 197 Clarendon St.

The Seaport District’s growing identity as a life science hub was a critical factor in BioMed’s interest in the property, O’Connor said. Vertex Pharmaceuticals was the first major corporate tenant to relocate from Cambridge in 2014, and is expanding with a second R&D site at the Innovation Square development at 6 Tide St. Cambridge-based Foundation Medicine is planning to relocate to a 580,000-square-foot build-to-suit headquarters under construction at 400 Summer St., and CRISPR Therapeutics of Cambridge leased 263,500 square feet in July at 105 West First St., a partnership between Tishman Speyer and Bellco Capital.

With the 601 Congress acquisition, BioMed owns nearly 5.9 million square feet in Greater Boston, comprising more than half of its 11.4 million-square-foot portfolio in the U.S. and United Kingdom.