Participation of thioredoxin in the V(V)-reduction reaction by Vanabin2

Ueki, Tomoyuki; Uwagaki, Masayuki; Yamamoto, Sohei; Michibata, Hitoshi

doi:10.1016/j.bbagen.2014.07.023

Cited by 7 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All vanabins share 18 conserved cysteine residues {C}-{X2-5}-{C} and are rich in positively charged amino acids, such as lysine and arginine. Vanabin2 in particular binds 20 V(IV) ions and catalyzes the reduction of V(V) to V(IV) in the presence of reduced glutathione (GSH) or reduced thioredoxin (Trx) (Ueki et al, 2003b;Fukui et al, 2003;Kawakami et al, 2009;Ueki et al, 2014). Thus, vanabins are dual-function proteins and may hold the key to identifying the mechanism underlying the highly selective and extremely high-level accumulation of vanadium ions.…”

Section: Introductionmentioning

confidence: 98%

Vanadium-Binding Ability of Nucleoside Diphosphate Kinase from the Vanadium-Rich Fan Worm, Pseudopotamilla occelata

et al. 2016

Self Cite

View full text Add to dashboard Cite

Polychaete fan worms and ascidians accumulate high levels of vanadium ions. Several vanadiumbinding proteins, known as vanabins, have been found in ascidians. However, no vanadium-binding factors have been isolated from the fan worm. In the present study, we sought to identify vanadiumbinding proteins in the branchial crown of the fan worm using immobilized metal ion affinity chromatography. A nucleoside diphosphate kinase (NDK) homolog was isolated and determined to be a vanadium-binding protein. Kinase activity of the NDK homologue, PoNDK, was suppressed by the addition of V(IV), but was unaffected by V(V). The effect of V(IV) on PoNDK precedes its activation by Mg(II). This is the first report to describe the relationship between NDK and V(IV). PoNDK is located in the epidermis of the branchial crown, and its distribution is very similar to that of vanadium. These results suggest that PoNDK is associated with vanadium accumulation and metabolism in P. occelata.

show abstract

Section: Introductionmentioning

confidence: 98%

Vanadium-Binding Ability of Nucleoside Diphosphate Kinase from the Vanadium-Rich Fan Worm, Pseudopotamilla occelata

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Enzymes belonging to the pentose phosphate pathway, such as glycogen phosphorylase [ 39 ], transketolase [ 40 ], and 6-phosphogluconate dehydrogenase [ 15 ], were counted in high numbers. A membrane V transporter (AsNramp) [ 17 ], redox protein (AsTrx) [ 26 ], and vanabin-interacting protein 1 (VIP1) [ 41 ] were also found, but in lower abundance. Several variants of VIP1 found in this analysis varied greatly in length and sequence, but their significance was unclear and they were not examined further in this study.…”

Section: Resultsmentioning

confidence: 99%

“…sydneiensis samea blood cells [ 12 , 24 ], as well as AgVanabin1 and AgVanabin2 through EST analysis of Ascidia gemmata intestinal tissue [ 25 ]. Vanabins were later found to act as V(V)-reductases [ 16 , 26 , 27 ]. Vanabins have 18 conserved cysteine residues, and form nine disulfide bonds to create a bow-shaped structure [ 28 ], although some of these disulfide bonds are reversible in redox [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

The acidic amino acid-rich C-terminal domain of VanabinX enhances reductase activity, attaining 1.3- to 1.7-fold vanadium reduction

Adi¹,

Fujie²,

Satoh³

et al. 2022

Biochemistry and Biophysics Reports

Self Cite

View full text Add to dashboard Cite

“…Its bow-shaped conformation consists of four α-helices with nine disulfide bonds between specific pairs of 18 conserved cysteine residues. The reduction mechanism has been theorized to occur through a cysteine thiol and disulfide exchange reaction of Vanabin2 coupled with the redox cycle of glutathione (GSH/GSSG) via glutathione reductase (GR). , The electron is given by nicotinamide adenine dinucleotide phosphate (scheme B).…”

Section: Introductionmentioning

confidence: 99%

Reversible Conversion of Disulfide/Dithiolate Occurring at a Vanadium(IV) Center: A Biomimetic System for Redox Exchange in Vanabin

et al. 2022

View full text Add to dashboard Cite

Ascidians use a class of cysteine-rich proteins generally referred to as vanabins to reduce vanadium ions, one of the many biological processes that involve the redox conversion between disulfide and dithiolate mediated by transition-metal ions.To further understand the nature of disulfide/dithiolate exchange facilitated by a vanadium center, we report herein a six-coordinate non-oxido V IV complex containing an unbound disulfide moiety,with TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidin-1-yl)oxyl) via hydrogen atom transfer. Importantly, complex 1 can be reduced by two electrons to form an eight-coordinate V IV complex, [V IV (PS3″) 2 ] 2− (4). The reaction can be reversed through a two-electron oxidation process to regenerate complex 1. The redox pathways both proceed through a common intermediate, [V(PS3″) 2 ] − (3), that has been previously reported as a resonance form of V V -dithiolate and a V IV -(thiolate)(thiyl-radical) species. This work demonstrates an unprecedented example of reversible disulfide/dithiolate interconversion mediated by a V IV center, as well as provides insights into understanding the function of V V reductases in vanabins.

show abstract

Participation of thioredoxin in the V(V)-reduction reaction by Vanabin2

Abstract: This study is the first to report the reduction of V(V) in the thioredoxin cascade.

Cited by 7 publications

References 34 publications

Vanadium-Binding Ability of Nucleoside Diphosphate Kinase from the Vanadium-Rich Fan Worm, Pseudopotamilla occelata

Vanadium-Binding Ability of Nucleoside Diphosphate Kinase from the Vanadium-Rich Fan Worm, Pseudopotamilla occelata

The acidic amino acid-rich C-terminal domain of VanabinX enhances reductase activity, attaining 1.3- to 1.7-fold vanadium reduction

Reversible Conversion of Disulfide/Dithiolate Occurring at a Vanadium(IV) Center: A Biomimetic System for Redox Exchange in Vanabin

Contact Info

Product

Resources

About