Active site properties of monomeric triosephosphate isomerase (monoTIM) as deduced from mutational and structural studies

  title={Active site properties of monomeric triosephosphate isomerase (monoTIM) as deduced from mutational and structural studies},
  author={Wolfgang Schliebs and Narmada Thanki and Ram{\'o}n Eritja and Rik K. Wierenga},
  journal={Protein Science},
MonoTIM is a stable monomeric variant of the dimeric trypanosomal enzyme triose phosphate isomerase (TIM) with less, but significant, catalytic activity. It is known that in TIM, three residues, Lys 13 (loop 1), His 95 (loop 4), and Glu 167 (loop 6) are the crucial catalytic residues. In the wild‐type TIM dimer, loop 1 and loop 4 are very rigid because of tight interactions with residues of the other subunit. Previous structural studies indicate that Lys 13 and His 95 have much increased… 
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