嗜盐嗜盐菌的DpsA同源物是一种铁蛋白。

The DpsA-homologue of the archaeon Halobacterium salinarum is a ferritin.

作者信息

Reindel Sabine, Anemüller Stefan, Sawaryn Andrzej, Matzanke Berthold F

机构信息

Isotopenlabor TNF, Medizinische Universität zu Lübeck, Ratzeburger Allee 160, Lübeck, Germany.

出版信息

Biochim Biophys Acta. 2002 Jul 29;1598(1-2):140-6. doi: 10.1016/s0167-4838(02)00361-8.

DOI:10.1016/s0167-4838(02)00361-8

PMID:12147354

Abstract

An iron-rich protein, DpsA(Hsal), was isolated from the archaeon Halobacterium salinarum sharing a sequence identity of 35% with the starvation-induced DNA-binding protein, DpsA, of Synechecoccus sp. PCC7942. It consists of 20-kDa subunits forming a dodecameric structure. The protein exhibits a ferric iron loading of up to 100 Fe ions per mole of holoprotein. CD spectra and secondary structure calculations are consistent with an alpha-helical contribution of 60%. The UV/VIS spectrum provides no evidence for the presence of heme groups. This protein exhibits features of a non-heme type bacterial ferritin (Ftn) although it shares only little sequence homology with Ftn. Molecular modelling disclosed a high structural similarity to E. coli Dps.

摘要

从嗜盐古菌盐生盐杆菌中分离出一种富含铁的蛋白质DpsA(Hsal)，它与聚球藻属PCC7942的饥饿诱导DNA结合蛋白DpsA的序列同一性为35%。它由20 kDa的亚基组成，形成十二聚体结构。该蛋白质每摩尔全蛋白的铁离子负载量高达100个铁离子。圆二色光谱和二级结构计算结果表明α-螺旋的贡献率为60%。紫外/可见光谱没有提供存在血红素基团的证据。尽管该蛋白质与细菌铁蛋白（Ftn）的序列同源性很低，但它具有非血红素型细菌铁蛋白的特征。分子建模显示它与大肠杆菌Dps具有高度的结构相似性。