PuSH - Publication Server of Helmholtz Zentrum München

Weiss, D.* ; Lütz, C. ; Lütz-Meindl, U.*

Photosynthesis and heat response of the green alga Micrasterias denticulata (Desmidiaceae).

Z. Naturforsch. C 54, 508-516 (1999)
Open Access Green as soon as Postprint is submitted to ZB.
Cells of the green alga Micrasterias denticulata cultivated at 15 degrees C, 20 degrees C or 25 degrees C were exposed to heat shocks at different temperatures (30-40 degrees C) for varying duration (5-90 min). Cell pattern formation, division rate as well as photosynthesis and respiration by measuring oxygen production and consumption have been studied. The degree of cell shape malformations was found dependent on the preceding cultivation temperature along with the mode of the heat shock. Cells cultivated at 15 degrees C and 20 degrees C could counteract a 90 min heat shock at 35 degrees C much better than those cultivated at 25 degrees C, which was seen by a less reduced young semicell. Cells cultivated at 15 degrees C and 25 degrees C reveal a reduced division activity compared to those grown at 20 degrees C even with a marked retardation when affected by a preceding heat shock. Photosynthesis and the level of plastid pigments (carotenoids, chlorophylls, beta-carotene, lutein) of controls determined by HPLC analysis reached a plateau after about 26 days when starting with 22-day old cultures. Photosynthesis and respiration were determined in a range between 15 degrees C and 40 degrees C in defined Micrasterias cell cultures of about this age (cultivation temperature 15 degrees C, 20 degrees C or 25 degrees C). Both processes rose steadily with increasing temperature starting with 15 degrees C and reached peaks between 30 degrees C and 32 degrees C, followed by a considerable drop when increasing the incubation temperature up to 40 degrees C. The experiments reveal that primary processes of energy formation and consumption are much less affected by temperature influences than cell shape formation and division rate.
Additional Metrics?
[➜Log in]
Edit extra informations Login
Publication type Article: Journal article
Document type Scientific Article
Keywords heat shock; Micrasterias; photosynthesis; pigments; temperature; ULTRASTRUCTURE; TEMPERATURE
ISSN (print) / ISBN 0939-5075
Journal Zeitschrift für Naturforschung - Section C
Quellenangaben Volume: 54, Issue: 7-8, Pages: 508-516 Article Number: , Supplement: ,
Publisher Verl. der Zeitschrift für Naturforschung
Reviewing status Peer reviewed
Institute(s) Research Unit Environmental Simulation (EUS)