The Atlanta office of Cushman & Wakefield will join Lincoln Property Co. Southeast in co-marketing and leasing 55 Allen Plaza, a 350,000-square-foot, Class-A office tower in downtown Atlanta that recently achieved LEED Gold certification.

Cushman & Wakefield is a longtime tenant of the building, which Lincoln Property Company Southeast has managed and leased since purchasing it on behalf of a pension fund client in 2011. The building opened in 2007.

Andy Sumlin, a Cushman & Wakefield agent who will join Lincoln Property Co. Southeast’s Leigh Braswell and Sabrina Altenbach on the 55 Allen Plaza leasing team, oversaw the leasing of the building several years ago while at Barry Real Estate Cos.

Overlooking the Downtown Connector on downtown Atlanta’s northern edge, 55 Allen Plaza is part of the Allen Plaza mixed-use development. The building is surrounded by amenities including restaurants, the W-Atlanta Downtown Hotel & Residences, retail and Centennial Olympic Park.

The Bread Box, a café that will serve breakfast, lunch and Starbucks coffee and also feature fresh-baked bread, will open in the building in October.

Carlyle’s Catering, a well-known Atlanta-based firm, will operate the café.

They join office tenants in the building including Ernst & Young, Skanska and the design firm ASD.

Lincoln Property Co. Southeast is overseeing the construction of three spec suites totaling 8,600 square feet. The suites are slated for completion by the end of the year and will offer clients space that is move-in ready, Braswell said.