Two types of 4,5-dioxovalerate reductases (NADPH) were partially purified and characterized from green alga, Chlorella regularis. The enzyme was separated by DEAE-Sephacel chromatography into two peaks: type I (first peak) and type II (second peak). The activity ratio of the type II to type I enzyme varied between 5 to 7 with a starting cell material. Both enzymes had the same pH optimum at 6.0 and pI value of 4.9. The molecular weight estimated by gel filtration was 33,000 for type I and 99,000 for type II enzyme. Both enzymes used only NADPH, but were not specific for 4,5-dioxovaleric acid (DOVA). Type I enzyme reduced glyoxylate 68-fold faster than DOVA, whereas type II enzyme acted more specifically on a variety of aldehydes than DOVA. It is suggested that these enzymes may not function primarily as NADPH-DOVA reductases in the metabolic pathway of DOVA.
|Number of pages||8|
|Journal||Plant and Cell Physiology|
|Publication status||Published - Jan 1986|
All Science Journal Classification (ASJC) codes
- Plant Science
- Cell Biology