Literature summary for 1.8.4.9 extracted from

Chen, F.F.; Chien, C.Y.; Cho, C.C.; Chang, Y.Y.; Hsu, C.H.
C-terminal redox domain of Arabidopsis APR1 is a non-canonical thioredoxin domain with glutaredoxin function (2019), Antioxidants (Basel), 8, 461 .

Cloned(Commentary)

Cloned (Comment)	Organism
recombinant expression of N-terminally GST-tagged C-terminal redox domain (amino acids 353-461) of AtAPR1 in Escherichia coli strain BL21(DE3)	Arabidopsis thaliana

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified recombinant detagged C-terminal redox domain of AtAPR1, sitting drop vapor diffusion method, crystallization from 100 mM Tris, pH 7.0, 1.0 M sodium citrate, and 200 mM sodium chloride, at 10°C, 1 week, X-ray diffraction structure determination and analysis at 2.70 A resolution, structure modeling via molecular replacement method using the J-Trx1 fragment of protein disulfide reductase ERdj5 from Mus musculus (PDB entry 3APQ), as the template	Arabidopsis thaliana

Crystallization (Comment)

Organism

purified recombinant detagged C-terminal redox domain of AtAPR1, sitting drop vapor diffusion method, crystallization from 100 mM Tris, pH 7.0, 1.0 M sodium citrate, and 200 mM sodium chloride, at 10°C, 1 week, X-ray diffraction structure determination and analysis at 2.70 A resolution, structure modeling via molecular replacement method using the J-Trx1 fragment of protein disulfide reductase ERdj5 from Mus musculus (PDB entry 3APQ), as the template

Arabidopsis thaliana

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
additional information	-	additional information	thermodynamic parameters for binding of AtAPR1 redox domain to GSH or GSSG	Arabidopsis thaliana

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
13000	-	recombinant detagged monomeric form of the AtAPR1 redox domain, gel filtration	Arabidopsis thaliana

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
AMP + sulfite + glutathione disulfide	Arabidopsis thaliana	-	adenylyl sulfate + 2 glutathione	-	?

Organism

Organism	UniProt	Comment	Textmining
Arabidopsis thaliana	P92979	-	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant N-terminally GST-tagged C-terminal redox domain of AtAPR1 from Escherichia coli strain BL21(DE3) by glutahione affinity chromatography, the tag is cleaved off by thrombin, followed by gel filtration	Arabidopsis thaliana

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
AMP + sulfite + glutathione disulfide	-	Arabidopsis thaliana	adenylyl sulfate + 2 glutathione	-	?
additional information	GSH is docked into the AtAPR1 redox domain active site by manual docking, superimposing the structures of glutaredoxin bound with GSH on that of the AtAPR1 redox domain. The structure of cGrx1 complexed with GSH (PDB code 4TR1) is used as a template. Interaction between GSH and the AtAPR1 redox domain is analyzed, binding structure analysis, overview	Arabidopsis thaliana	?	-	-

Subunits

Subunits	Comment	Organism
More	the recombinant detagged monomeric form of the AtAPR1 redox domain has 13 kDa measured by SDS-PAGE. Because plant APR1 is arranged as oligomers, this result implies that the oligomerization of AtAPR1 is not formed via redox domain self-interaction. The structure of the AtAPR1 redox domain is a compact spherical molecule comprising a central core of five-stranded beta-sheets flanked on either side by four helices. The fold of the redox domain arranged in the order beta1-alpha1-beta2-alpha2-beta3-alpha3-beta4-beta5-alpha4 is similar to the thioredoxin fold but not glutaredoxin fold. The N-terminal region begins with a short beta1 strand (residues Val4-Leu6), followed by alpha1 and beta2, consisting of residues Arg8 to Lys16 and Trp24 to Tyr29, respectively. The redox-active motif (Cys33-Pro34-Phe35-Cys36) is located at the N-terminal end of the alpha2-helix, consisting of residues Pro34 to Leu50. The strand beta3 comprises residues Lys56 to Arg61, followed by beta4 (Thr81-Phe85), beta5 (Ile93-Tyr95) and a C-terminal helix which consists of residues Lys99 to Glu111. Strands beta1, beta2, and beta3 are parallel, and strand beta4 is antiparallel to beta2 and beta5. Helices alpha1 and alpha3 pack on one side of the central beta-sheet, whereas helices alpha2 and alpha4 are located at opposite sides. The packing of the sandwich-like architecture is mainly maintained by hydrophobic interactions between the sheet and helices. Surface potential distribution of the redox domain shows most positive-charged residues around the redox-active motif	Arabidopsis thaliana

Synonyms

Synonyms	Comment	Organism
adenosine 5'-phosphosulfate reductase	-	Arabidopsis thaliana
APR	-	Arabidopsis thaliana
APR1	-	Arabidopsis thaliana
APS reductase	-	Arabidopsis thaliana
AtAPR1	-	Arabidopsis thaliana

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
25	-	assay at	Arabidopsis thaliana

Temperature Stability [°C]

Temperature Stability Minimum [°C]	Temperature Stability Maximum [°C]	Comment	Organism
additional information	-	thermal denaturation of the AtAPR1 redox domain presents a highly thermoreversible property, melting temperature can be roughly estimated as 55°C. The secondary structure of the redox domain is greatly distorted on heating to 55°C by estimating from a series of CD spectra at various temperatures. The CD spectra for the AtAPR1 redox domain, which is 95°C thermal-denatured followed by cooling to 25°C, is almost identical to that of the native AtAPR1 redox domain measured at 25°C. This indicates that thermal denaturation of the redox domain is reversible	Arabidopsis thaliana

pH Optimum

pH Optimum Minimum	pH Optimum Maximum	Comment	Organism
7	-	assay at	Arabidopsis thaliana

General Information

General Information	Comment	Organism
malfunction	a C-terminal truncated plant-type APR lacking the redox domain losses APR activity but recovers the function after the addition of thioredoxin	Arabidopsis thaliana
metabolism	in contrast to the cooperation of a sulfonucleotide reductase and a thioredoxin in prokaryote systems, in plants, the protein involved in the pathway is only a single polypeptide which consists of two distinct domains: a sulfonucleotide reductase-like one and a thioredoxin-like one	Arabidopsis thaliana
additional information	the C-terminal domain of APR acts as a glutathione-dependent reductase. The crystal structure of the C-terminal redox domain of Arabidopsis APR1 (AtAPR1) shows a conserved alpha/beta thioredoxin fold, but not a glutaredoxin fold, crystal structure analysis, folding of the AtAPR1 redox domain is measured by circular dichroism (CD) spectroscopy, overview. The C-terminal redox domain of APR is more similar to thioredoxin than glutaredoxin. Molecular model of AtAPR1 redox domain in complex with GSH, structure modeling, overview	Arabidopsis thaliana
physiological function	adenosine 5'-phosphosulfate (APS) reductase (APR) plays a vital role in catalyzing the reduction of activated sulfate to sulfite, which requires glutathione. APR activity is downregulated to avoid tissue injury by a negative feedback regulation, a mechanism associated with metabolic changes that cause reduced GSH concentration and the accumulation of sulfate	Arabidopsis thaliana