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Updated: Jun 24, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
Toward a mechanism for biliprotein lyases: revisiting nucleophilic addition to phycocyanobilin
Jun-Ming Tu1, Ming Zhou, Rainer Haessner
1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, P.R. China.
Abstract:
Biliprotein lyases attach linear-tetrapyrrolic bilins covalently to apoproteins, which is a prerequisite for the assembly of phycobiliproteins into phycobilisomes, the light-harvesting complexes of cyanobacteria. On the basis of the addition of thiol and imidazole to phycocyanobilin, we propose a generalized lyase reaction mechanism. The adducts contain isomerized phycocyanobilin that can be transferred by the lyase to apoproteins by either back-isomerization, generating phycocyanobilin-containing proteins, or direct transfer, generating phycoviolobilin-containing proteins.
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