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Autofluorescence Imaging to Evaluate Red Algae Physiology
Published on: February 17, 2023
Protochlorophyll(ide) in a Blue-Green Alga
J Myers1, J R Graham, R T Wang
1Department of Botany, The University of Texas, Austin, Texas 78712.
Plant Physiology
|February 1, 1982
Summary
Anacystis nidulans accumulates protochlorophyllide under far-red light. This pigment was also detected in other algae species exposed to far-red light conditions.
Area of Science:
- Photosynthesis research
- Algal pigment analysis
- Photobiology
Background:
- Chlorophyll is the primary pigment for photosynthesis.
- Far-red light is a specific light spectrum (>650 nm).
- Protochlorophyllide is a precursor to chlorophyll.
Purpose of the Study:
- To investigate protochlorophyllide accumulation in Anacystis nidulans under far-red light.
- To determine if protochlorophyllide is present in other algae species grown under similar light conditions.
Main Methods:
- Cultivating Anacystis nidulans and other algal species (blue-green and red algae) under far-red light (>650 nm).
- Measuring whole cell fluorescence spectra to identify pigments.
- Quantifying protochlorophyllide concentrations relative to chlorophyll.
Main Results:
- Anacystis nidulans accumulated protochlorophyllide to approximately one-tenth the concentration of chlorophyll when grown under far-red light.
- Protochlorophyll(ide) was identified in another blue-green alga and a red alga also grown in far-red light.
Conclusions:
- Far-red light exposure leads to protochlorophyllide accumulation in Anacystis nidulans.
- The presence of protochlorophyllide under far-red light is not unique to Anacystis nidulans, as it was also observed in other algal species.
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