Catalyzes the phosphorylation of pantothenate (Pan), the first step in CoA biosynthesis. Cannot utilize a phosphoryl donor other than ATP. (R)-pantothenate + ATP = (R)-4'-phosphopantothenate + ADP + H(+) Monovalent cations. Ammonium or potassium. Not regulated by feedback inhibition by CoA and its thioesters as described for many other pantothenate kinases. Not inhibited by N-pentylpantothenamide (N5-Pan), and this compound cannot act as a substrate either. Cofactor biosynthesis; coenzyme A biosynthesis; CoA from (R)-pantothenate: step 1/5. Homodimer. Belongs to the type III pantothenate kinase family.