Campbell K A, Gregor W, Pham D P, Peloquin J M, Debus R J, Britt R D
Department of Chemistry, University of California, Davis, California 95616, USA.
Biochemistry. 1998 Apr 14;37(15):5039-45. doi: 10.1021/bi9800552.
An S1-state parallel polarization "multiline" EPR signal arising from the oxygen-evolving complex has been detected in spinach (PSII) membrane and core preparations depleted of the 23 and 17 kDa extrinsic polypeptides, but retaining the 33 kDa extrinsic protein. This S1-state multiline signal, with an effective g value of 12 and at least 18 hyperfine lines, has previously been detected only in PSII preparations from the cyanobacterium sp. Synechocystis sp. PCC6803 [Campbell, K. A., Peloquin, J. M., Pham, D. P., Debus, R. J., and Britt, R. D. (1998) J. Am. Chem. Soc. 120, 447-448]. It is absent in PSII spinach membrane and core preparations that either fully retain or completely lack the 33, 23, and 17 kDa extrinsic proteins. The S1-state multiline signal detected in spinach PSII cores and membranes has the same effective g value and hyperfine spacing as the signal detected in Synechocystis PSII particles. This signal provides direct evidence for the influence of the extrinsic PSII proteins on the magnetic properties of the Mn cluster.
在菠菜（PSII）膜和去除了23 kDa和17 kDa外在多肽但保留了33 kDa外在蛋白的核心制剂中，检测到了由放氧复合体产生的S1态平行极化“多线”EPR信号。这种S1态多线信号，有效g值为12且至少有18条超精细线，此前仅在蓝藻集胞藻PCC6803的PSII制剂中检测到[坎贝尔，K.A.，佩洛金，J.M.，范，D.P.，德布斯，R.J.，和布里特，R.D.（1998）《美国化学会志》120，447 - 448]。在完全保留或完全缺乏33 kDa、23 kDa和17 kDa外在蛋白的菠菜PSII膜和核心制剂中不存在该信号。在菠菜PSII核心和膜中检测到的S1态多线信号与在集胞藻PSII颗粒中检测到的信号具有相同的有效g值和超精细间距。该信号为外在PSII蛋白对锰簇磁性质的影响提供了直接证据。
