Table 2. Average r.m.s. differences (Å) between the C^α atoms of Alr_Sas and other alanine racemases.

The numbers in parentheses denote sequence identity with Alr_Sas. Residues from the other structures equivalent to those in Alr_Sas were used for the superpositions.

Alanine racemase	PDB code	Whole monomers†	N-terminal domain‡	C-terminal domain§	Active site¶
AlrGst	1sft	1.34 (44%)	1.25 (44%)	0.71 (48%)	0.48 (70%)
AlrBax	3ha1	1.54 (43%)	1.47 (43%)	0.75 (46%)	0.53 (68%)
AlrMtb	1xfc	1.67 (33%)	1.62 (32%)	1.13 (36%)	0.72 (51%)
DadXPao	1rcq	2.14 (30%)	1.60 (29%)	1.36 (32%)	0.82 (47%)

^†Calculated using monomer A.

^‡Calculated using residues 2–241.

^§Calculated using residues 242–382.

^¶Calculated using residues 37–43, 61–65, 82–86, 101–105, 127–140, 163–171, 198–205, 216–223 and 351–358 from monomer A and residues 263–266, 309–314 and 283–287 from monomer B.