TY  - GEN
A1  - Riedel, Simona
A1  - Siemiatkowska, Beata
A1  - Watanabe, Mutsumi
A1  - Müller, Christina S.
A1  - Schünemann, Volker
A1  - Hoefgen, Rainer
A1  - Leimkühler, Silke
T1  - The ABCB7-Like Transporter PexA in Rhodobacter capsulatus Is Involved in the Translocation of Reactive Sulfur Species
T2  - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe
N2  - The mitochondrial ATP-binding cassette (ABC) transporters ABCB7 in humans, Atm1 in yeast and ATM3 in plants, are highly conserved in their overall architecture and particularly in their glutathione binding pocket located within the transmembrane spanning domains. These transporters have attracted interest in the last two decades based on their proposed role in connecting the mitochondrial iron sulfur (Fe–S) cluster assembly with its cytosolic Fe–S cluster assembly (CIA) counterpart. So far, the specific compound that is transported across the membrane remains unknown. In this report we characterized the ABCB7-like transporter Rcc02305 in Rhodobacter capsulatus, which shares 47% amino acid sequence identity with its mitochondrial counterpart. The constructed interposon mutant strain in R. capsulatus displayed increased levels of intracellular reactive oxygen species without a simultaneous accumulation of the cellular iron levels. The inhibition of endogenous glutathione biosynthesis resulted in an increase of total glutathione levels in the mutant strain. Bioinformatic analysis of the amino acid sequence motifs revealed a potential aminotransferase class-V pyridoxal-50-phosphate (PLP) binding site that overlaps with the Walker A motif within the nucleotide binding domains of the transporter. PLP is a well characterized cofactor of L-cysteine desulfurases like IscS and NFS1 which has a role in the formation of a protein-bound persulfide group within these proteins. We therefore suggest renaming the ABCB7-like transporter Rcc02305 in R. capsulatus to PexA for PLP binding exporter. We further suggest that this ABC-transporter in R. capsulatus is involved in the formation and export of polysulfide species to the periplasm.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 740 
KW  - ABCB7
KW  - persulfide
KW  - polysulfide
KW  - glutathione
KW  - ABC transporter
KW  - Walker A motif
KW  - pyridoxal-50-phosphate
Y1  - 1019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-434975
SN  - 1866-8372
IS  - 740
ER  - 
TY  - JOUR
A1  - Riedel, Simona
A1  - Siemiatkowska, Beata
A1  - Watanabe, Mutsumi
A1  - Müller, Christina S.
A1  - Schünemann, Volker
A1  - Hoefgen, Rainer
A1  - Leimkühler, Silke
T1  - The ABCB7-Like Transporter PexA in Rhodobacter capsulatus Is Involved in the Translocation of Reactive Sulfur Species
JF  - Frontiers in Microbiology
N2  - The mitochondrial ATP-binding cassette (ABC) transporters ABCB7 in humans, Atm1 in yeast and ATM3 in plants, are highly conserved in their overall architecture and particularly in their glutathione binding pocket located within the transmembrane spanning domains. These transporters have attracted interest in the last two decades based on their proposed role in connecting the mitochondrial iron sulfur (Fe–S) cluster assembly with its cytosolic Fe–S cluster assembly (CIA) counterpart. So far, the specific compound that is transported across the membrane remains unknown. In this report we characterized the ABCB7-like transporter Rcc02305 in Rhodobacter capsulatus, which shares 47% amino acid sequence identity with its mitochondrial counterpart. The constructed interposon mutant strain in R. capsulatus displayed increased levels of intracellular reactive oxygen species without a simultaneous accumulation of the cellular iron levels. The inhibition of endogenous glutathione biosynthesis resulted in an increase of total glutathione levels in the mutant strain. Bioinformatic analysis of the amino acid sequence motifs revealed a potential aminotransferase class-V pyridoxal-50-phosphate (PLP) binding site that overlaps with the Walker A motif within the nucleotide binding domains of the transporter. PLP is a well characterized cofactor of L-cysteine desulfurases like IscS and NFS1 which has a role in the formation of a protein-bound persulfide group within these proteins. We therefore suggest renaming the ABCB7-like transporter Rcc02305 in R. capsulatus to PexA for PLP binding exporter. We further suggest that this ABC-transporter in R. capsulatus is involved in the formation and export of polysulfide species to the periplasm.
KW  - ABCB7
KW  - persulfide
KW  - polysulfide
KW  - glutathione
KW  - ABC transporter
KW  - Walker A motif
KW  - pyridoxal-50-phosphate
Y1  - 2019
U6  - https://doi.org/10.3389/fmicb.2019.00406
SN  - 1664-302X
VL  - 10
PB  - Frontiers Media
CY  - Lausanne
ER  -