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(+) Inhibited by acetyl-CoA (PubMed:17825826). Inhibited by calcium hopantenate (PubMed:17379144). Activated by palmitoylcarnitine (PubMed:17825826). Cofactor biosynthesis; coenzyme A biosynthesis; CoA from (R)-pantothenate: step 1/5. Homodimer. Single knockout mice show a reduction in pantothenate kinase (PANK) activity of about 30% and 60% in the liver and brain respectively. Pank1 and Pank2 double knockout mice develop progressively severe hypoglycemia and hyperketonemia by postnatal day 10 leading to their death by day 17. A reduction in PANK activity of about 90-95% seen in the liver and brain and hepatocytes show reduced NADH levels. Belongs to the type II pantothenate kinase family. Extended N-terminus. Extended N-terminus.