ISSN:
1432-072X
Keywords:
Algal heating damage
;
Anacystis nidulans
;
Cyanobacterial pigments
;
Phycobilin bleaching
;
Phycobilisomes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Exposure of blue-green or red algal cells to temperatures exceeding 60–65°C for several minutes resulted in bleaching of all phycobilin absorption in the visible range, with virtually no alteration in chlorophyll or carotenoid absorption. Difference spectra of non-bleached vs bleached cells appeared identical to absorption spectra of purified phycobilisomes isolated from the same cell culture in high phosphate medium. All phycobilin chromophores were bleached at approximately the same rate during heating. There were no changes in apparent molecular weights or relative amounts of the phycobilisome apoproteins during chromophore bleaching. Phycobilisomes in cell extracts from Anacystis nidulans resisted bleaching when suspended in medium of high phosphate concentration, but were bleached at 60–65°C within a few minutes when placed in diluted medium. The results indicate that phycobilisomes in vivo are stabilized by a mechanism other than high osmotic and ionic strength. This represents a rapid and quantitative method to characterize the phycobiliprotein content of cyanobacteria and red algae in vivo.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00446927
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