Table III. HMGR interactions with substrate.

A. Interactions with CoA
Group	CoA atom	HMGR atom	Distancea
Adenine	N3A	N567 ND2	3.0–3.2
	ring	Y479 side chain	∼3.0–4.0
	C5A or C6A	A564 CB	3.6–3.7
Ribose-3′P	O7A	Y479 OH	2.6
	O9A	R571 NH2	4.0–5.0
Ribose	O2*A (2′OH)	N567 OD1	3.0–3.2
diphosphate	O1A (Pα)	K722 NZ	2.6–2.7
	O4A (Pβ)	K722 NZ	2.6–2.7
		R568 NH1	3.0–3.1
Pantothenate	O9P	S852 OG	2.9–3.0
	O5P	S565 OG	2.7–2.8
	N4P	H866 NE2	2.9–3.8
	N8P	S865 OG	3.1–3.4
B. Interactions with NADP+
Groupb	NADP atom	HMGR atom	Distancea
Adenine	AN6	D653 OD2	3.1–3.4
	AN1	D653 N	2.8–2.9
	ring	F628 side chain	∼3.5
	ring	V805 CG1 and CG2	∼3.8–4.5
Ribose-A-2′P	AOP1	S626 OG	2.5–2.6
		Water	2.6–2.9
	AOP3	R627 NH1	3.1–3.8
		R627 N	2.8–3.1
Ribose-A	AO5*	R871 NH1	3.1–3.2
diphosphate	AO2 (Pα)	N658 ND2	2.9–3.0
		R871 NH1	3.9–3.1
	NO1 (Pβ)	G656 N	2.6–2.8
		M655 N	3.1–3.4
		Water	2.7–2.9
	NO2 (Pβ)	M657 N	3.6–3.7
		M659 N	2.9–3.1
Ribose-N	NO4*	N658 ND2	3.4–3.5
	NO2*	D767 OD2	2.6–2.7
	NO3*	N870 ND2	3.0–3.6
		Water	2.8–3.0
Nicotinamide	NN1	E559 OE1	3.1–3.3
	NN7	N658 OD1	3.2–3.6
	NC4	M657 CG	2.9–3.6
	NO7	R590 NH2	2.4–2.7

C. Interactions of HMG with hHMGRc or pmHMGRd
Group	Atom 1	hHMGR	Distancea	pmHMGR	Distancea
Carboxylate	O3	K735 NZ	2.6–2.7
	O4	S684 OG	2.5–2.6	R261 NH2	2.6
		K692 NZ	3.1–3.3
3-methyl	C6	L853 CD2	3.9	A368 CB	3.7
3-hydroxyl	O7	D690 OD2	2.6–2.8
		R590 NH2	3.0–3.3
Carbonyl	O2	K691 NZ	2.7–2.9	K267 NZ	2.8
		E559 OE2	2.5–2.6	E83 OE2	2.9
		N755 ND2	2.7–2.8	N271 OD1	3.2
	C1	NADP NC4	2.9–3.1	NAD NC4	4.0
hHMGR-D767	OD2	E559 OE1	3.6–3.7	E83 OE1	3.0
(pmHMGR-D283)	OD2	K691 NZ	2.6–2.7	K267 NZ	3.3

^aAll distances are in Å. For human HMGR, distances are taken from the form C structure, and the distance range for the four crystallographically independent molecules is reported.

^bRibose-A corresponds to the ADP ribose, ribose-N to the nicotinamide ribose of NADP.

^chHMGR, human HMGR.

^dpmHMGR, P.mevalonii HMGR (PDB code 1qax).