Research Article

Crystal Structures of the Putative Isocitrate Dehydrogenase from Sulfolobus tokodaii Strain 7 in the Apo and NADP+-Bound Forms

Table 2

Possible hydrogen bonds of the 2-phosphate moiety.

(Å)

ST2166 (open)
 OP3–Lys335 (NZ)2.8
 OP2–Tyr336 (OH)2.8
 OP2–Arg386 (NH1)3.1
ApIDH (open)
 OP2–Tyr349 (OH)3.6
 OP2–Arg400 (NH1)3.1
ApIDH (closed)
 OP1–Lys348 (NZ)4.0
 OP3–Tyr349 (OH)2.5
 OP2–Arg296 (NH1)3.4
 OP2–Gln292 (NE2)3.9
EcIDH (closed)
 OP1–Tyr345 (OH)2.6
 OP3–Tyr391 (OH)2.7
 OP2–Arg395 (NH1)3.0
 OP2–Arg395 (NH2)2.5
 OP2–Arg395 (NH2)2.6

Distances of less than 4.0 Å between hydrogen bond partners of the 2-phosphate moiety of NADP+ and IDH.