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Manganese is essential for activity of allantoate amidinohydrolase from Chlamydomonas reinhardtii
- Source :
-
Plant Science . Aug2003, Vol. 165 Issue 2, p423. 6p. - Publication Year :
- 2003
-
Abstract
- Allantoicase (allantoate amidinohydrolase, EC 3.5.3.4) from Chlamydomonas reinhardtii catalyses the degradation of allantoate to (−)ureidoglycolate and of (+)ureidoglycolate to glyoxylate, in both cases with urea as the other product. Allantoicase activity purified in buffers without any cations increased after manganese addition to the assay mixture reaching a saturation maximun with 0.25 mM. The allantoicase activity was strongly inhibited after EDTA treatment. The activity of the EDTA-treated enzyme was restored after incubation with Mn2+, whereas the incubation with Cu2+ resulted in a fully inactivated preparation. Others cations tested (Ca2+, Fe2+, Mg2+, Zn2+, Co2+) had no effect on activity. The same results were obtained independently of the substrate used in all the experiments performed. A manganese-depleted allantoicase, obtained by purification with manganese free buffers, bound radioactive manganese in vitro. This binding is strong since enzyme retained the radioactive cation after gel chromatography and SDS-PAGE. Results obtained are the first clear demonstration of manganese binding in vitro to any allantoate-degrading enzyme from a photosynthetic organism and that manganese is essential for allantoicase activity. [Copyright &y& Elsevier]
- Subjects :
- *MANGANESE
*CHLAMYDOMONAS reinhardtii
Subjects
Details
- Language :
- English
- ISSN :
- 01689452
- Volume :
- 165
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- Plant Science
- Publication Type :
- Academic Journal
- Accession number :
- 10119724
- Full Text :
- https://doi.org/10.1016/S0168-9452(03)00203-6