Premium
EFFECTS OF LIGHT AND GLYCEROL ON THE ORGANIZATION OF THE PHOTOSYNTHETIC APPARATUS IN THE FACULTATIVE HETEROTROPH PYRENOMONAS SALINA (CRYPTOPHYCEAE) 1
Author(s) -
Lewitus Alan J.,
Caron David A.,
Miller Kenneth R.
Publication year - 1991
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1111/j.0022-3646.1991.00578.x
Subject(s) - biology , thylakoid , heterotroph , photosynthesis , glycerol , phycoerythrin , chlorophyll a , photosynthetic pigment , ultrastructure , botany , autotroph , chlorophyll , photosystem , chloroplast , biophysics , photosystem ii , biochemistry , bacteria , flow cytometry , genetics , gene
The marine cryptophyte Pyrenomonas salina Santore is capable of autotrophic and heterotrophic nutrition. We studied the physiological and ultrastructural changes that accompany the shift between these nutritional modes. The addition of glycerol to batch cultures of P. salina, grown at an irradiance limiting for photoautotrophic growth, increased its growth rate and induced specific biochemical and structural changes in its photosynthetic system. Results from extracted pigment analyses, thin‐section electron microscopy, and freeze‐fracture electron microscopy indicated that glycerol addition reduced the cell phycoerythrin content, phycoerythrin to chlorophyll a ratio, degree of thylakoid packing, number of thylakoids · cell −1 , and PSII particle size. These properties were reduced to a similar extent in cells grown photoautotrophically under an irradiance saturating for growth. These results are consistent with the hypothesis that enhancement of heterotrophic potential occurs at the expense of light‐harvesting ability in glycerol‐grown P. salina .