一种代表铁硫蛋白中一个亚型的铁硫蛋白：光谱、生化及稳定性研究。

A Rieske ferredoxin typifying a subtype within Rieske proteins: spectroscopic, biochemical and stability studies.

作者信息

Kletzin Arnulf, Ferreira Ana S, Hechler Torsten, Bandeiras Tiago M, Teixeira Miguel, Gomes Cláudio M

机构信息

Institute of Microbiology and Genetics, Darmstadt University of Technology, Schnittspahnstrasse 10, 64287 Darmstadt, Germany.

出版信息

FEBS Lett. 2005 Feb 14;579(5):1020-6. doi: 10.1016/j.febslet.2004.12.075. Epub 2005 Jan 13.

DOI:10.1016/j.febslet.2004.12.075

PMID:15710385

Abstract

A new subtype of archaeal Rieske ferredoxin (RFd) has been identified in the genome of the thermoacidophilic archaeon Acidianus ambivalens. The gene is inserted in an atypical genomic context in a gene cluster encoding a NiFe hydrogenase. Sequence and phyletic analysis showed that the protein is related to bacterial RFd but not to any of the known archaeal Rieske proteins. The recombinant 14 kDa protein isolated from Escherichia coli behaved as a dimer in solution. It contained approximately 2 Fe/mol and all visible and EPR spectroscopic features typical of Rieske centre-containing proteins. However, its redox potential (+170 mV) was significantly higher than those of canonical RFd. This difference is rationalized in terms of the protein structure environment, as discrete amino acid substitutions in key positions around the metal centre account for the higher potential.

摘要

在嗜热嗜酸古菌嗜酸两面菌（Acidianus ambivalens）的基因组中鉴定出了一种新型的古菌铁硫蛋白（RFd）亚型。该基因插入到编码镍铁氢化酶的基因簇中的一个非典型基因组环境中。序列和系统发育分析表明，该蛋白与细菌RFd相关，但与任何已知的古菌铁硫蛋白均无关联。从大肠杆菌中分离出的重组14 kDa蛋白在溶液中表现为二聚体。它每摩尔含有约2个铁原子，具有含铁硫中心蛋白典型的所有可见光谱和电子顺磁共振光谱特征。然而，其氧化还原电位（+170 mV）明显高于典型RFd的氧化还原电位。根据蛋白质结构环境可以解释这种差异，因为金属中心周围关键位置的离散氨基酸取代导致了更高的电位。