Catalyzes the phosphorylation of pantothenate to generate 4'-phosphopantothenate in the first and rate-determining step of coenzyme A (CoA) synthesis. (R)-pantothenate + ATP = (R)-4'-phosphopantothenate + ADP + H(+) Subject to allosteric regulation, exists in two distinct conformational states, a catalytically incompetent (or open) conformation stabilized by the binding of acetyl(acyl)-CoA, and a catalytically competent (or closed) conformation stabilized by ATP-binding (By similarity). Acetyl-CoA and its thioesters act as allosteric inhibitors and compete with the ATP-binding site (By similarity). Strongly inhibited by acetyl-CoA, malonyl-CoA and palmitoyl CoA and modestly inhibited by CoA (PubMed:16040613). Inhibited by calcium hopantenate (PubMed:17379144). Cofactor biosynthesis; coenzyme A biosynthesis; CoA from (R)-pantothenate: step 1/5. Homodimer. Highly expressed in the liver. Belongs to the type II pantothenate kinase family.