sentences:  4-coumaroyl-CoA and three units of malonyl-CoA are converted into three molecules of carbon dioxide, four molecules of coenzyme A and one unit of naringenin chalcone.CHS exists as a homodimeric protein with each monomer approximately 42-45 kDa in size.Each monomer possesses a β-keto synthase (KS) activity that catalyzes the sequential head to tail incorporation of two-carbon acetate units into a growing polyketide chain.