Catalyzes the phosphorylation of pantothenate (Pan), the first step in CoA biosynthesis. (R)-pantothenate + ATP = (R)-4'-phosphopantothenate + ADP + H(+) Not regulated by feedback inhibition by CoA and its thioesters as described for many other pantothenate kinases. Competitively inhibited by N-pentylpantothenamide (N5-Pan) and N-heptylpantothenamide (N7-Pan), although these compounds can also act as substrates, being converted to inactive CoA analogs which inhibit a number of cellular targets, especially fatty acid biosynthesis. Cofactor biosynthesis; coenzyme A biosynthesis; CoA from (R)-pantothenate: step 1/5. Homodimer. Belongs to the type II pantothenate kinase family.