TMP, uridine 2', 3', or 5' monophosphates, or deoxyuridine 3' or 5' monophosphates + H2O => thymidine or (deoxy)uridine + orthophosphate [NT5C]

Cytosolic 5'3'-nucleotidase (NT5C) catalyzes the hydrolysis of uridine 2', 3', and 5' monophosphates, dexoyuridine 3' and 5' monophosphates, and thymidine monophosphate to yield the corresponding (deoxy)nucleosides and orthophosphate. The active form of the enzyme is a homodimer, with an absolute requirement for Mg++ (Hoglund and Reichard 1990; Rampazzo et al. 2000). This enzyme appears to play a central role in the "substrate cycles" that regulate cytosolic deoxynucleotide levels (Gazziola et al. 2001).

细胞质5'3'-核苷酸酶(NT5C)催化尿苷2',3'和5'单磷酸、脱氧尿苷3'和5'单磷酸以及胸苷单磷酸的水解反应，生成相应的(脱氧)核苷和正磷酸。该酶的活性形式为同源二聚体，对Mg++有绝对需求（Hoglund和Reichard 1990；Rampazzo等2000）。此酶似乎在调节细胞质脱氧核苷酸水平的“底物循环”中扮演核心角色（Gazziola等2001）。