   4.4.1.29 | physiological function |
sSingle and double mutant strains for lyase subunits cpcSI and cpcU exhibit slower growth rates, reduced apo-phycobiliprotein levels, and impaired assembly of phycobilisomes. A cpcSI cpcU cpcT triple mutant is nearly devoid of apo-phycobiliprotein. The cpcSI and cpcU mutants produce an altered form of the phycocyanin beta-subunit, which has a mass about 588 Da smaller than the wild-type protein. The modified phycobilisomes from the cpcsI, cpcU, and cpcSIcpcU mutant strains carry a phycocyanobilin chromophore at Cys153 of CpcB but not at Cys82. Both CpcSI and CpcU are required for covalent attachment of phycocyanobilin to Cys82 of the phycocyanin subunit |
732032 |
