CenterPoint Energy Inc. said Thursday it signed an agreement to buy the former Neiman Marcus building in downtown Minneapolis from United Properties.

The purchase price wasn't disclosed and may not be finalized until next year. In addition, the firm will also spend to remodel the four-story, 100,000-square-foot building, said CenterPoint spokeswoman Becca Virden. The building, at 505 Nicollet Mall, has been empty since Neiman Marcus Group of Dallas closed its department store there earlier this year.

Bloomington-based United Properties bought the building, which is separate from the Gaviidae II shopping center, for $5.5 million in a deal that closed in January. It will become the natural gas utility's main downtown location in 2015 after the remodeling, Virden said.

CenterPoint plans to move 255 employees who now work in 67,000 square feet of space in the LaSalle Plaza Building, where the company has a lease that expires in 2016, she said. Those workers have administrative, sales, marketing, call center and IT jobs.

CenterPoint, based in Houston, serves 806,000 natural gas customers in Minnesota. It has 1,300 employees in the state, including about 900 in Minneapolis.

CenterPoint wanted a downtown presence that it can brand with its name and will use it to showcase some energy-saving ideas and services, such as energy-efficient lighting and techniques to improve heating and cooling, Virden said. The building also provides easy access to light-rail and bus lines, and proximity to Minneapolis city officials with whom the company frequently deals, she said.

Its new location along the city's retail spine is also close to some of the most heated development activity downtown.

Across S. 5th Street, Opus Development Corp. is building a $100 million, 26-story, 253-unit luxury apartment tower called Nic on Fifth. On the same block, Xcel Energy Inc. is planning a nine-story corporate campus extension across Nicollet Mall from its headquarters. And Mortenson Development has proposed a 30-story, 262-unit apartment tower called 4Marq at the corner of S. 4th Street and Marquette Avenue.

Next to the Neiman Marcus building, the 510 Marquette building was recently sold to developer Ned Abdul of Swervo Development Corp. for $6.7 million. And, kitty-­corner from the 400 block at S. 5th Street and Marquette Avenue, the 98-year-old Soo Line Building is being converted from offices into 250 luxury apartments by the Michigan-based developer Village Green.

Staff writer Janet Moore contributed to this report.

Steve Alexander • 612-673-4553