SAN DIEGO -- Pharmaceutical giant Pfizer Inc. announced Monday that it plans to consolidate its research and development operations to five locations, including one in La Jolla.

Following its $68 billion acquisition of rival Wyeth last month, Pfizer plans to close six of its 20 research and development facilities and layoff an undisclosed number of employees. In addition to the five research and development hubs, Pfizer will also operate nine specialized units around the world.

The company's five main research and development centers will be located in Cambridge, Mass.; Groton, Conn.; Pearl River, N.Y.; Sandwich, U.K.; and La Jolla.

"By focusing our R&D operations in these centers, we are building the world's premier biopharmaceutical R&D enterprise," said Mikael Dolsten, president of Pfizer's BioTherapeutics Research & Development. "This new structure puts Pfizer in the best position to conduct cutting-edge research within and beyond our own laboratories and to deliver a portfolio of high-impact medicines to patients."

The restructuring will reduce Pfizer's global research and development square footage by 35 percent.

Gov. Arnold Schwarzenegger applauded Pfizer for including La Jolla as one of its global research and development hubs.

"California has always been a leader in biotech research and innovation and Pfizer's announcement that it will establish California as one (of) the five hubs of its worldwide R&D network is fantastic news for our state," Schwarzenegger said in a statement. "Today's announcement will not only ensure that our state continues as a leader in this growing field, but it will also help stimulate our economy and save and create jobs when we need them most."