Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
Faculty of Life Sciences, Toyo University, 1-1-1 Izumino Itakura Oura-gun, Gunma 374-0193, Japan.
Chem Res Toxicol. 2024 Feb 19;37(2):212-215. doi: 10.1021/acs.chemrestox.3c00341. Epub 2024 Jan 22.
Microcystin-degrading bacteria first degrade microcystins by microcystinase A (MlrA) to cleave the cyclic structure of microcystins at the Adda-Arg site of microcystin-LR, microcystin-RR, and microcystin-YR, but the cleavage of the other microcystins was not clear. In our study, the microcystin-degrading bacterium sp. C-1 as wild type and that of -disrupting mutant, sp. CMS01 were used for microcystins biodegradation. The results showed MlrA degraded microcystin-LA, microcystin-LW, microcystin-LY, microcystin-LF, and nodularin. MlrA could cleave the Adda-L-amino acid site.
微囊藻毒素降解菌首先通过微囊藻毒素酶 A（MlrA）降解微囊藻毒素，在微囊藻毒素-LR、微囊藻毒素-RR 和微囊藻毒素-YR 的 Adda-Arg 位点切开微囊藻毒素的环状结构，但其他微囊藻毒素的切割情况尚不清楚。在本研究中，使用野生型微囊藻毒素降解菌 sp. C-1 和微囊藻毒素酶 A 基因敲除突变株 sp. CMS01 进行微囊藻毒素的生物降解。结果表明，MlrA 可降解微囊藻毒素-LA、微囊藻毒素-LW、微囊藻毒素-LY、微囊藻毒素-LF 和节球藻毒素。MlrA 可以切割 Adda-L-氨基酸位点。
