Oxygen‐dependent H2O2 production by Rubisco

• Published in: FEBS letters Vol. 571; no. 1-3; pp. 124 - 128
• Main Authors: Kim, Kangmin, Portis, Archie R
• Format: Journal Article
• Language: English
• Published: England 30.07.2004
• Subjects: Carbon metabolism; Chlamydomonas reinhardtii; Hydrogen Peroxide - metabolism; KABP, 3′-ketoarabinitol-1,5-bisphosphate; Kinetics; Oxidation; Oxygen - metabolism; Oxygenases - metabolism; PDBP, d-glycero-2,3-pentodiulose-1,5-bisphosphate; Photosynthesis; Rhodospirillum rubrum; Ribulose-Bisphosphate Carboxylase - metabolism; Rubisco, ribulose-1,5-bisphosphate carboxylase/oxygenase; RuBP, d-ribulose-1,5-bisphosphate; Spinacia oleracea; Spinacia oleracea - enzymology; XuBP, d-xylulose-1,5-bisphosphate
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2004.06.064

Oxygen and ribulose‐1,5‐bisphosphate dependent, H2O2 production was observed with several wild type Rubisco enzymes using a sensitive assay. H2O2 and d‐glycero‐2,3‐pentodiulose‐1,5‐bisphosphate, a known and potent inhibitor of Rubisco activity, are predicted products arising from elimination of H2O2 from a peroxyketone intermediate, specific to oxygenase activity. Parallel assays using varying CO2 and O2 concentrations revealed that the partitioning to H2O2 during O2 consumption by spinach Rubisco was constant at 1/260–1/270. High temperature (38 °C), which reduces Rubisco specificity for CO2 versus O2, increased the rates of H2O2 production and O2 consumption, resulting in a small increase in partitioning to H2O2 (1/210). Two Rubiscos with lower specificity than spinach exhibited greater partitioning to H2O2 during catalysis: Chlamydomonas reinhardtii (1/200); and Rhodospirillum rubrum (1/150).