Photosynthesis, lipids and proteins in the cyanobacteriumSynechocystis PCC 6803 as affected by temperature

Abstract

The cyanobacteriumSynechocystis PCC 6803 was grown photoautotrophically in an inorganic medium at constant growth temperatures of 20, 38 (control) or 43°C for 9 h. The up and down-shift of cultivation temperature decreased the growth as measured by culture absorbance and chlorophylla content. However, high temperature slightly increased the oxygen evolution while temperature lower than control inhibited oxygen evolution during the whole incubation period. The protein synthesis studied by14C-labeled protein declined under low temperature by about 50%. The fatty acid pattern is characterized as lacking in C20/C22 acids but containing large amounts of C16 and C18 polyunsaturated fatty acids, 16:2 and 18:3 in particular. The lower temperature increased the percentage of monounsaturated fatty acids while higher temperature increased the saturated fatty acid content in total lipids and lipid classes studied.