Structural insights into the mechanism defining substrate affinity in Arabidopsis thaliana dUTPase: the role of tryptophan 93 in ligand orientation

Table 1 Comparison of secondary structures and interactions at the ligand-binding site

	A. thaliana	S. cerevisiae	H. sapiens	E. coli	M. tuberculosis
PDB ID	4OOP	3P48	2HQU	1RN8	2PY4
Sequence similarity^a	Self	56.2 %	63.9 %	35.5 %	39.2 %
K _m	0.4 ± 0.1 μM	13.2 ± 0.6 μM	3.6 ± 1.9 μM	0.5 μM (SE 17 %)	0.46 ± 0.2 μM
α helix 1st res	S89	S69	S86	S72	S65
α helix 5th res	W93	V73	A90	H76	T69
α1st–WAT–α5th	Present	Absent	Absent	Absent	Absent
References	This study	Tchigvintsev et al. [19]	Toth et al. [15]	Barabas et al. [11]	Pecsi et al. [17]

α1st–WAT–α5th refers to the presence of an interaction among the first residue of the α helix, a water molecule, and the fifth residue of the α helix
^aSequence similarities between Arabidopsis and each species were calculated by using SIM [28] on the ExPASy server (http://www.expasy.org)

ISSN: 1756-0500