O’Reilly Automotive, one of the nation’s largest auto parts retailers, is expanding its Chattanooga presence with a new store even as the company consolidates after buying a rival.

The company is building its 24th store in the region at 5005 Highway 58 in Harrison near Ace Hardware. The 6,800-square-foot store is expected to open in late May with five to seven workers, said Mark Merz, director of investor relations.

The Strauss Co. Inc., the general contractor, expects to finish construction and turn the store over to O’Reilly for opening preparations by May 19, said Kate Gilbert, business manager for Strauss and project manager for the O’Reilly site.

“There’s not been a lot of recent development on Highway 58,” Ms. Gilbert said. “So I get a lot of phone calls from people asking about it.”

The auto parts store is being built near AutoZone and Advance Auto Parts.

O’Reilly on April 1 announced it has signed an agreement to buy rival CSK Auto Corp. for $500 million, plus about $500 million of debt, according to the companies’ Web sites. O’Reilly will become the nation’s third-largest auto parts chain with about 3,200 stores.

The two companies had pro forma revenues last year of about $4.4 billion, the Web sites state. There are no CSK stores in the area, Mr. Merz said.

The O’Reilly store isn’t the only development occurring on Highway 58.

Greg Hurley of GVH & Associates said he is doing site work on a 9-acre parcel across from Sweeney’s Pit Bar-B-Q. Crews are grading a hill on the site and are relocating utilities, and should finish by summer, said Mr. Hurley, the site’s developer. Recent rains have slowed the work.

Plans for the site are incomplete, he said. He may build a shopping center, or may divide the property in six or seven outparcels. Mr. Hurley said he has received expressions of interest from several banks, restaurants and discount retailers.

Highway 58 could become a hot construction zone in the near future, Ms. Gilbert said. A number of real estate agents are placing “for sale” signs on undeveloped parcels on the highway.