TABLE 2.

Conservation of OTC surface residues whose replacements do not destabilize mutant protein and cause OTC deficiency.

Residue ID	Conservation scorea	Amino acids in OTC from other species
		Mammals	Birds	Reptiles	Amphibians	Fish	Invertebrates
D41	66	D/H	D	D	D/N	H/S	D/H/N/T
N47	52	D/N/T	N	N	D/N/H	D/A	D/G/H/N/Y
G50	40	G/E/A	G/A/T/V	A/P	A	G/A/S/P	G/A/E/K/P/Q/R/S
E52	98	E/D	E	E/D	E/D	E	E/D
K80	99	K	K	K	K	K	K/R/H
T125	68	T/I/M/R/K	I/R	M/S	K/Q/R	T/A/G/V/K/R	I/L/K/R/N/Q/S/Y/P
D136	81	D	N	D	D	D	D
D165	91	D/E	D/N	D	D	D/E	D/E
E181	99	E	E	E	E	E	E/D
K210	97	K	K/Q	K/R	K	K	K/R/P
D249	91	D/E/N	D	D/N/V	D/E	D/E/N	D/N
K289	50	K	K/Q	E/Q	K/Q	K/E/Q/N	K/E/N
E297	72	D/N	N/D	D/G	D/N	D/N/G	D/E/N/H/R
R320	74	R/K/Q	R/Q	K/Q	R/K	R/H/L	R/K/H/N/Q/E

^aConservation scores were determined as percent of 270 OTC homologs that have the same amino acid as human protein at that position.