Abstract
A pinky strain was obtained from the culture of Rhodobacter sphaeroides R26.1, a carotenoidless mutant, which we have been depositing in a freezer (hereafter, call these the pinky strain and "R26.1"). The pinky strain started to grow in the culture of "R26.1", when exposed to white light. Carotenoids extracted from the pinky strain were analyzed by an HPLC apparatus equipped with a diode-array detector. The electronic absorption spectra of a set of carotenoids showed that the pinky strain contained several different carotenoids with the number of conjugated double bonds, n=10, 11 and 12, the major component being carotenoids with n=11. This type of carotenoid composition has never been found either in Rhodobacter sphaeroides or in other purple bacteria. We are now trying (1) to determine the structures of carotenoids extracted from the pinky strain, and (2) to sequence the 16S rDNAs from the pinky strain, "R26.1",and the authentic R26.1.
