May play a role in maintaining a redox balance during environmental and functional hypoxia. Exhibits high specificity for taurine and in addition, requires both alpha amino group and C-2 carbon chain length as a critical factor for active site binding of the amino acid. A methyl group in the beta position may be critical for active site binding of the keto acid. In the reverse reaction requires NAD(H) for the activity but not NADP(H). H2O + NAD(+) + tauropine = H(+) + NADH + pyruvate + taurine Subject to substrate inhibition by pyruvate for the reverse reaction but not for the forward reaction of the tauropine dehydrogenase activity. Optimum pH is 8.5 for the forward reaction, and 6.6-7.3 for the reverse reaction. The half-maximal rate is observed at 6.8 for the forward reaction, and at 5.5-7.9 for the reverse reaction. Belongs to the lysopine/nopaline/octopine/opine/vitopine dehydrogenases family.