RT Journal Article
SR Electronic
T1 Bistablity in Fluorescence from a purple non-sulfur bacteria
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 132498
DO 10.1101/132498
A1 Anirban Bose
A1 Sufi O Raja
A1 Sanhita Ray
A1 Anjan Kr Dasgupta
YR 2017
UL http://biorxiv.org/content/early/2017/06/04/132498.abstract
AB Bistable optical emission has been observed for photosynthetic purple non-sulfur bacteria Rhodobacter capsulatus SB1003. The microbes respond to UV excitation (at 395nm) in two different manners, one in which fluorescence emission in the range 590-685nm is amplified with respect to time, and the other state corresponds to diminishing fluoresence. This switching can be observed at room temperature 298K when fluorophore (or bacterial) concentration is gradually increased. If temperature is lowered a steady quenching of fluorescence is observed. However presence of a weak magnetic field of the order of (less than 0.5 T) is introduced. We propose that aggregation of bacterial porphyrin induced by photon excitation may lead to such bistablity. Possibility of photon driven cellular communication through such porphyrin aggregation is suggested.