Open AccessRegulation of proline oxidase activity by lactate.
Author(s) -
Edward M. Kowaloff,
James M. Phang,
Anne Granger,
Sylvia J. Downing
Publication year - 1977
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.74.12.5368
Subject(s) - proline , gluconeogenesis , biochemistry , lactic acidosis , enzyme , oxidase test , lactic acid , biology , acidosis , chemistry , amino acid , bacteria , endocrinology , genetics
We found that proline oxidase, the first enzyme of the proline degradative pathway, is inhibited by lactate. The Km of the enzyme for proline increases with increasing concentrations of lactate. Since proline can be a source for gluconeogenesis, regulation of proline degradation by lactate may serve as a mechanism for allocation of metabolic fuel sources. The marked inhibition of proline oxidase at levels of lactate that commonly occur in both genetic and acquired lactic acidosis may cause the previously unexplained hyperprolinemia seen in these metabolic disorders.