Functional Impact of the N-terminal Arm of Proline Dehydrogenase from Thermus thermophilus
AbstractProline dehydrogenase (ProDH) is a ubiquitous flavoenzyme that catalyzes the oxidation of proline to Δ1-pyrroline-5-carboxylate. Thermus thermophilus ProDH (TtProDH) contains in addition to its flavin-binding domain an N-terminal arm, consisting of helices αA, αB, and αC. Here, we report the biochemical properties of the helical arm truncated TtProDH variants ΔA, ΔAB, and ΔABC, produced with maltose-binding protein as solubility tag. All three truncated variants show similar spectral properties as TtProDH, indicative of a conserved flavin-binding pocket. ΔA and ΔAB are highly active tetramers that rapidly react with the suicide inhibitor N-propargylglycine. Removal of the entire N-terminal arm (ΔABC) results in barely active dimers that are incapable of forming a flavin adduct with N-propargylglycine. Characterization of V32D, Y35F, and V36D variants of ΔAB established that a hydrophobic patch between helix αC and helix α8 is critical for TtProDH catalysis and tetramer stabilization. View Full-Text
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Huijbers, M.M.E.; van Alen, I.; Wu, J.W.; Barendregt, A.; Heck, A.J.R.; van Berkel, W.J.H. Functional Impact of the N-terminal Arm of Proline Dehydrogenase from Thermus thermophilus. Molecules 2018, 23, 184.
Huijbers MME, van Alen I, Wu JW, Barendregt A, Heck AJR, van Berkel WJH. Functional Impact of the N-terminal Arm of Proline Dehydrogenase from Thermus thermophilus. Molecules. 2018; 23(1):184.Chicago/Turabian Style
Huijbers, Mieke M.E.; van Alen, Ilona; Wu, Jenny W.; Barendregt, Arjan; Heck, Albert J.R.; van Berkel, Willem J.H. 2018. "Functional Impact of the N-terminal Arm of Proline Dehydrogenase from Thermus thermophilus." Molecules 23, no. 1: 184.
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