[Formation of free radicals at photoreduction of allophycocyanin B].
A photoinduced ESR signal is detected in the presence of 10(-2) M of dithionine in phycobilisomes and in fractions enriched in allophycocyanin B. The signal is characterized by the line width of 12G and g-factor of 2.004. It is demonstrated that the appearance of the free radicals is related to photoreduction of allophycocyanin B.