Gene Ontology annotation through association of InterPro records with GO terms
Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator judgment of sequence similarity
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Gene Ontology annotation based on curation of immunofluorescence data
Automatic Gene Ontology annotation based on Rhea mapping
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Towards a proteome-scale map of the human protein-protein interaction network.
Over-expression in Escherichia coli and characterization of two recombinant isoforms of human FAD synthetase.
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First characterization of the two human FAD synthetase isoforms (products of FLAD1); both have FMN adenylyltransferase (FAD synthase) activity with a strict Mg2+ requirement.
"Both isoforms possessed FADS activity and had a strict requirement for MgCl(2)"
Mitochondrial localization of human FAD synthetase isoform 1.
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Isoform 1 (with an N-terminal cleavable mitochondrial targeting sequence) localizes to mitochondria, whereas isoform 2 is cytosolic; recombinant hFADS1 is enzymatically active on FMN.
"hFADS1, but not hFADS2, localizes in mitochondria"
The antibiotics roseoflavin and 8-demethyl-8-amino-riboflavin from Streptomyces davawensis are metabolized by human flavokinase and human FAD synthetase.
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Human FAD synthetase converts RoFMN to RoFAD but does not accept AFMN, defining substrate scope of the FMN adenylyltransferase activity.
"Consequently, roseoflavin adenine dinucleotide (RoFAD) was synthesized by the latter enzyme"
Human FAD synthase (isoform 2): a component of the machinery that delivers FAD to apo-flavoproteins.
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Purified recombinant isoform 2 catalyzes FAD assembly from ATP and FMN (and, much more slowly, pyrophosphorolysis); FAD release appears rate-limiting, implying tight control of FAD synthesis and delivery.
"the enzyme catalyzes FAD assembly from ATP and FMN"
Bacterial over-expression and purification of the 3'phosphoadenosine 5'phosphosulfate (PAPS) reductase domain of human FAD synthase: functional characterization and homology modeling.
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The isolated C-terminal PAPS-reductase domain is sufficient to catalyze FAD synthesis (and cleavage), localizing the FMN adenylyltransferase activity to that domain; the N-terminal MPTb domain is regulatory, not strictly required for catalysis.
"the PAPS reductase domain, per se, is able to catalyze the typical reactions of the FADS: FAD synthesis and its cleavage."
Significance of redox-active cysteines in human FAD synthase isoform 2.
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Redox-active cysteines in the PAPS-reductase (FAD-synthesizing) domain modulate FAD synthesis; thiol-blocking reagents inhibit the reaction, indicating a cysteine-based redox switch.
"FAD synthesis is also inhibited by thiol-blocking reagents, suggesting the involvement of free cysteines in the hFADS2 catalytic cycle."
A proteome-scale map of the human interactome network.
Remaining challenges in cellular flavin cofactor homeostasis and flavoprotein biogenesis.
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Recombinant isoform 2 synthesizes FAD via an ordered bi-bi mechanism and acts as a FAD chaperone, directly delivering FAD to client apo-flavoproteins (LSD1/KDM1A and dimethylglycine dehydrogenase); FADS is present in nucleus, cytosol and mitochondria.
"A direct transfer of the cofactor from hFADS2 to apo-dimethyl glycine dehydrogenase was also demonstrated."
Human FAD synthase is a bi-functional enzyme with a FAD hydrolase activity in the molybdopterin binding domain.
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Human FADS hydrolyzes FAD to FMN via its N-terminal molybdopterin-binding domain in a Co2+/mersalyl-dependent reaction, establishing the bifunctional FAD diphosphatase activity distinct from the C-terminal synthase.
"The recombinant hFADS2 was able to hydrolyse added FAD in a Co(2+) and mersalyl dependent reaction."
The hidden side of the human FAD synthase 2.
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The N-terminal FADHy (MPTb) domain hydrolyzes FAD (Co2+/K+ stimulated, Vmax exceeding that of FAD synthesis) and other ADP-dinucleotides; NADH inhibits and reduced glutathione stimulates the activity, linking NAD and FAD homeostasis.
"Co2+ induced FAD hydrolysis was strongly stimulated in the presence of K+, reaching a Vmax higher than that of FAD synthesis."
Extensive disruption of protein interactions by genetic variants across the allele frequency spectrum in human populations.
Dual proteome-scale networks reveal cell-specific remodeling of the human interactome.
Quantitative high-confidence human mitochondrial proteome and its dynamics in cellular context.
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FLAD1 detected in high-confidence mitochondrial proteome, consistent with the mitochondrial isoform 1.
"Quantitative high-confidence human mitochondrial proteome and its dynamics"
Structural insights into the bifunctional enzyme human FAD synthase.
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Crystal structure of full-length hFADS2 and its C-terminal PAPS domain with FAD; the C-terminal domain synthesizes FAD while the N-terminal MPTb+KH domains form the FAD-hydrolase active site; the enzyme is a C2-symmetric homodimer.
"the C-terminal domain tightly binds FAD and catalyzes its synthesis, while the combination of the N-terminal molybdopterin-binding and KH domains is the minimal essential substructure required for the hydrolysis of FAD"
Multimodal cell maps as a foundation for structural and functional genomics.
Vitamin B2 (riboflavin) metabolism