Structural analysis of cytochrome f from the psychrophillic alga Chlamydomonas subcaudata

摘要

The psychrophillic green alga C. subcaudata was collected from the ice-covered Antarctic Lake Bonney, where it grows 15-17 m below ice cover under a unique combination of extremely low light (less than 50 mu mol m~(-2) s~(-1)), low temperature (between 0 deg C to 6 deg C) and high salinity (0.7M) (Lizotte & Priscu, 1992). C. subcaudata differs from the mesophillic green alga C. reinhardtii in pigment composition, light utilization, LHCI:LHCII ratios, enhanced capacity for cyclic electron flow aroundPSI and is unable to undergo state transitions (Morgan et al., 2001). Thus, it was suggested that C. subcaudata is a natural state transition mutant. In addition, cyt f from C. subcaudata exhibits a lower apparent molecular mass than that from C. reinhardtii.