Constructing energy maps of metabolic cycles

The original equation of Kharash takes into account only the bond types, while the modified one also takes into consideration functional groups (Biochemical Education 23, 83-85, 1995). Kharash equation: H = 220k + 105l (2) Modified equation: H = 220h + 105l +185 li + 60m 340 n- 20p (3) where h represents the number of double boundsk and l are the same as in eqn 2, and m, n and p stand for oxo, hydroxy and carboxyl groups, respectively. In eqns 2 and 3, k is the number of C-C, C-H bonds and l is the number of C-N and H-N bonds. However, in eqn 3 the number (185) belonging to l is different from that in eqn 2, where it is 105. The modified eqn 3 correctly is: H = 280h + 220k + 105 l + 60m + 40n - 20p