Transmembrane topology of the Rieske Fe/S protein of the cytochrome <i>b<sub>6</sub>/f</i> complex from spinach chloroplasts

Karnauchov, Ivan; Herrmann, Reinhold G.; Klösgen, Ralf Bernd

doi:10.1016/s0014-5793(97)00427-4

Cited by 49 publications

(44 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here we show the overexpression of PetC proteins from mesophilic organisms in their native form with incorporated iron-sulfur cluster. The fact that all three overexpressed PetC proteins were localized in inclusion bodies or cell membranes of E. coli but not in the soluble cell fraction argues for the existence of a membrane anchor in these proteins similar to other Rieske proteins (4).…”

Section: Heterologous Overexpression Of Functional Rieske Proteins-mentioning

confidence: 94%

“…The Rieske protein consists of an N-terminal transmembrane ␣-helix, which anchors the protein in the membrane (3,4), and a large soluble domain on the luminal side of the membrane. The three-dimensional structure of this luminal part has been solved both for the Rieske protein of a cytochrome b 6 f complex (5) and of a cytochrome bc 1 complex (6) to a resolution of 1.8 and 1.5 Å, respectively.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

Schneider

Skrzypczak

Anemüller

et al. 2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

The completely sequenced genome of the cyanobacterium Synechocystis PCC6803 contains three open reading frames, petC1, petC2, and petC3, encoding putative Rieske iron-sulfur proteins. After heterologous overexpression, all three gene products have been characterized and shown to be Rieske proteins as typified by sequence analysis and EPR spectroscopy. Two of the overproduced proteins contained already incorporated iron-sulfur clusters, whereas the third one formed unstable aggregates, in which the FeS cluster had to be reconstituted after refolding of the denatured protein.Although EPR spectroscopy showed typical FeS signals for all Rieske proteins, an unusual low midpoint potential was revealed for PetC3 by EPR redox titration. Detailed characterization of Synechocystis membranes indicated that all three Rieske proteins are expressed under physiological conditions. Both for PetC1 and PetC3 the association with the thylakoid membrane was shown, and both could be identified, although in different amounts, in the isolated cytochrome b 6 f complex. The considerably lower redox potential determined for PetC3 indicates heterogeneous cytochrome b 6 f complexes in Synechocystis and suggests still to be established alternative electron transport routes.The functional core of cytochrome bc complexes consists of three subunits, which are a b-type cytochrome, a c-type cytochrome, and the Rieske iron-sulfur protein (1). In contrast to the cytochrome bc 1 complex of mitochondria and bacteria with three subunits, cytochrome b, cytochrome c 1 , and the Rieske protein, the homologous cytochrome b 6 f complex of chloroplasts and cyanobacteria contains four core subunits named cytochrome b 6 , subunit IV, cytochrome f, and the Rieske protein (2).The Rieske protein consists of an N-terminal transmembrane ␣-helix, which anchors the protein in the membrane (3, 4), and a large soluble domain on the luminal side of the membrane. The three-dimensional structure of this luminal part has been solved both for the Rieske protein of a cytochrome b 6 f complex (5) and of a cytochrome bc 1 complex (6) to a resolution of 1.8 and 1.5 Å, respectively. The redox active [2Fe-2S] cluster, which is bound by the luminal domain, is ligated by two cysteine and two histidine residues with one iron being ligated by the two cysteines and the other by the two histidines. It is likely that this unusual coordination causes the high midpoint potential of about ϩ100 to ϩ400 mV. Besides these coordinating amino acids there are two additional cysteine residues, which form a disulfide bridge close to the ironsulfur cluster. In the amino acid sequence the coordinating amino acids as well as the additional cysteines are organized in two boxes with highly conserved sequences in all cytochrome bc complexes. It was shown that substitutions of single amino acids within or around these boxes affect the midpoint potential of the Rieske proteins (7) and that this midpoint potential can be predicted to some extent from the amino acid sequence. Proteins with the sequence CP...

show abstract

Section: Heterologous Overexpression Of Functional Rieske Proteins-mentioning

confidence: 94%

mentioning

confidence: 99%

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

Schneider

Skrzypczak

Anemüller

et al. 2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…After 30 min at room temperature, unbroken cells were removed by centrifugation at 2,000 rpm for 10 min. The supernatant fraction (cell extract, 3 ml) was applied to the top of a step gradient (6 ml of 20% sucrose and 2 ml of 60% sucrose in buffer A) and spun for 3.5 hr at 4°C in a Beckman SW41 rotor (16). The material at the 20%/60% sucrose interface (membrane) was collected, suspended in 12 ml of buffer A, and pelleted by centrifugation in a SW41 rotor at 40,0000 rpm for 3.5 hr at 4°C.…”

Section: Methodsmentioning

confidence: 99%

High-affinity binding of hemimethylated oriC by Escherichia coli membranes is mediated by a multiprotein system that includes SeqA and a newly identified factor, SeqB

Shakibai

Ishidate

Reshetnyak

et al. 1998

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The binding of hemimethylated oriC to Escherichia coli membranes has been implicated in the prevention of premature reinitiation at newly replicated chromosomal origins in a reaction that involves the SeqA protein. We describe the resolution of the membrane-associated oriCbinding activity into two fractions, both of which are required for the high-affinity binding of hemimethylated oriC. The active component in one fraction is identified as SeqA. The active component of the second fraction is a previously undescribed protein factor, SeqB. The reconstituted system reproduced the salient characteristics of the membraneassociated binding activity, suggesting that the membraneassociated oriC-binding machinery of E. coli is likely to be a multiprotein system that includes the SeqA and SeqB proteins.In Escherichia coli and most other bacterial species, chromosome replication is initiated at a specific point during the cell cycle (1). It is clear that a mechanism exists to prevent premature reinitiation until the proper time in the cell cycle is reached (2). Several factors have been proposed to play a role in the sequestration of newly replicated origins to prevent premature reinitiation during the eclipse period.The methylation state of the chromosomal origin has been implicated both in the binding of oriC to membranes and in the prevention of premature reinitiation at newly replicated origins. In E. coli, adenine residues within chromosomal GATC sequences are methylated in a reaction catalyzed by Dam methylase. Because the methylation reactions occur after replication, adenine residues within GATC sequences in the newly synthesized strand remain unmethylated for a period of time. The oriC region contains a high density of GATC sites, and methylation of adenine residues at several of these sites is delayed significantly relative to the time of methylation at GATC sites elsewhere in the chromosome (3, 4). As a result, the oriC region of newly replicated chromosomes remains hemimethylated for about 30-40% of the cell cycle.Evidence that hemimethylated oriC does not serve as an effective template for initiation of replication in vivo came from the finding of Russell and Zinder (5) that a fully methylated oriC plasmid was unable to replicate in a Dam

show abstract

“…NaCl, NaSCN, and Na 2 CO 3 treatments were performed as described (40). Trypsin digestion was performed as described (41).…”

mentioning

confidence: 99%

A Putative Chloroplast Thylakoid Metalloprotease VIRESCENT3 Regulates Chloroplast Development in Arabidopsis thaliana

Qi¹,

Liu²,

Liang

et al. 2016

Journal of Biological Chemistry

View full text Add to dashboard Cite

The chloroplast is the site of photosynthesis and many other essential plant metabolic processes, and chloroplast development is an integral part of plant growth and development. Mutants defective in chloroplast development can display various color phenotypes including the intriguing virescence phenotype, which shows yellow/white coloration at the leaf base and greening toward the leaf tip. Through large scale genetic screens, we identified a series of new virescent mutants including virescent3-1 (vir3-1), vir4-1, and vir5-1 in Arabidopsis thaliana. We showed that VIR3 encodes a putative chloroplast metalloprotease by map-based cloning. Through site-directed mutagenesis, we showed that the conserved histidine 235 residue in the zinc binding motif HEAGH of VIR3 is indispensable for VIR3 accumulation in the chloroplast. The chloroplast localization of VIR3 was confirmed by the transient expression of VIR3-GFP in leaf protoplasts. Furthermore, taking advantage of transgenic lines expressing VIR3-FLAG, we demonstrated that VIR3 is an intrinsic thylakoid membrane protein that mainly resides in the stromal lamellae. Moreover, topology analysis using transgenic lines expressing a dual epitope-tagged VIR3 indicated that both the N and C termini of VIR3 are located in the stroma, and the catalytic domain of VIR3 is probably facing the stroma. Blue native gel analysis indicated that VIR3 is likely present as a monomer or part of a small complex in the thylakoid membrane. This work not only implicates VIR3 as a new factor involved in early chloroplast development but also provides more insight into the roles of chloroplast proteases in chloroplast biogenesis.Chloroplasts not only serve as the site of photosynthesis but also are responsible for the production of many essential metabolites in higher plants. Although a descendant of photosynthetic prokaryotic organisms through endosymbiosis, the chloroplast has evolved many unique features including complex regulatory networks to achieve the coordinated expressions of plastid genome and nuclear genome and the coordination of chloroplast development with leaf development (1, 2). Given the importance of the chloroplast, much research has been directed at dissecting the intricate pathways that regulate chloroplast development. One fruitful way has been the identification of mutants that are defective in nuclear genes for chloroplast proteins. Large scale genetic screens have revealed that mutants of nuclear genes for chloroplast proteins can give rise to myriads of visible leaf color phenotypes ranging from albino, yellow, and pale green to virescence and variegation (3).Among the many types of mutants that are associated with chloroplast defects are the intriguing virescent mutants. These mutants display young and emerging tissues that are deficient of photosynthetic pigments, a sign that is often associated with underdeveloped plastids (2, 4). As leaves expand, however, these tissues gradually become greener along the leaf proximaldistal axis. At the whole plant level, the ce...

show abstract

Transmembrane topology of the Rieske Fe/S protein of the cytochrome b₆/f complex from spinach chloroplasts

Cited by 49 publications

References 31 publications

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

High-affinity binding of hemimethylated oriC by Escherichia coli membranes is mediated by a multiprotein system that includes SeqA and a newly identified factor, SeqB

A Putative Chloroplast Thylakoid Metalloprotease VIRESCENT3 Regulates Chloroplast Development in Arabidopsis thaliana

Contact Info

Product

Resources

About

Transmembrane topology of the Rieske Fe/S protein of the cytochrome b6/f complex from spinach chloroplasts

Cited by 49 publications

References 31 publications

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

Heterogeneous Rieske Proteins in the Cytochrome b6 f Complex of Synechocystis PCC6803?

High-affinity binding of hemimethylated oriC by Escherichia coli membranes is mediated by a multiprotein system that includes SeqA and a newly identified factor, SeqB

A Putative Chloroplast Thylakoid Metalloprotease VIRESCENT3 Regulates Chloroplast Development in Arabidopsis thaliana

Contact Info

Product

Resources

About

Transmembrane topology of the Rieske Fe/S protein of the cytochrome b₆/f complex from spinach chloroplasts