Changes of C-phycocyanin in synechococcus 6301 in relation to growth on various sulfur compounds

Abstract

The cyanobacterium Synechococcus 6301 is able to use a lim ited number of sulfur com pounds as the only source of sulfur supply such as sulfate, thiosulfate, thioacetic acid, mercaptoacetic acid, thioacetamide, L-cysteine and glutathione.Com pounds containg thioether linkages such asmethionin or S-m ethylcysteine and all com pounds investigated so far containing sulfonic acid structures do not support growth.Growth inhibiton was observed by addition of am inom ethanesulfonic acid or cysteamine. When non-growth sustaining sulfur com pounds are added as sulfur source, the C-phycocyanin content of the Synechococcus cultures decreased drastically, causing a shift in color from bluegreen to yellow-green.An analysis reveals the degradation of C-phycocyanin whereas chlorophyll formation still proceeds to a certain degree in growing sulfur-starved cells.Supplem entation of a suitable sulfur source induces a period of intense and preferential C-phycocyanin synthesis prior to resumption of normal growth. © 1982, Walter de Gruyter. All rights reserved.