The Activity of the Peroxidase System in the Course of Stress-Induced CAM Development

The Activity of the Peroxidase System in the Course of Stress-Induced CAM Development The activity of the peroxidase system in Mesembryanthemum crystallinum L. plants in relation to the shift from C3 to CAM photosynthesis was studied. In detached leaves of the fourth and fifth stories treated with NaCl (0.3 M), a rapid (after 30 min) transient induction of the ionically bound peroxidase (the first maximum) was observed followed by a second weak increase in the enzyme activity (90 min after salt treatment). In the leaves of intact plants, which received a longer treatment with NaCl, a two-phase change in the enzyme activity was also observed. It was most pronounced at the early stages of the NaCl-induced plant shift from C3 to CAM photosynthesis. In this case, in both detached and intact leaves of juvenile plants, the activity of soluble peroxidase was at a low steady-state level. The situation changed dramatically when M. crystallinum plants transitioned to the reproductive developmental phase and photosynthesis switched from C3 to CAM. The time dependence of the activities of both peroxidase types, the soluble ones in particular, was characterized by marked diurnal oscillations (light–dark), which coincided with the fluctuations of the total titratable acidity. In this case, the activity of the soluble enzyme was several orders of magnitude higher than the activity of the ionically bound peroxidase, even though the optimum pH for both isoforms was similar (pH 5.0). Three acid isoforms of soluble peroxidases, which operated more actively when the cytoplasm had a higher acidity, were distinguished by isoelectrofocusing. Their activity increased under salinity. Alkaline and neutral components were predominant in more than 30 molecular forms of the soluble peroxidase detected. We concluded that the operation of the peroxidase system changed substantially when plants shifted from the juvenile to the reproductive state and switched from C3 to CAM photosynthesis: the activity of stress-induced ionically bound peroxidase was drastically inhibited with a concurrent increase in the activity of soluble peroxidase and a change in the spectrum of its molecular forms. Russian Journal of Plant Physiology Springer Journals

The Activity of the Peroxidase System in the Course of Stress-Induced CAM Development

Loading next page...
Kluwer Academic Publishers-Plenum Publishers
Copyright © 2002 by MAIK “Nauka/Interperiodica”
Life Sciences; Plant Sciences
Publisher site
See Article on Publisher Site


You’re reading a free preview. Subscribe to read the entire article.

DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches


Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.



billed annually
Start Free Trial

14-day Free Trial