Annotations: 1SC5

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1sc5a1	All alpha proteins	DNA/RNA-binding 3-helical bundle	Sigma3 and sigma4 domains of RNA polymerase sigma factors	Sigma3 domain	Sigma factor sigma-28 (FliA)	(Aquifex aeolicus ) [TaxId: 63363 ],	SCOPe (2.08)
A	d1sc5a2	All alpha proteins	DNA/RNA-binding 3-helical bundle	Sigma3 and sigma4 domains of RNA polymerase sigma factors	Sigma4 domain	Sigma factor sigma-28 (FliA)	(Aquifex aeolicus ) [TaxId: 63363 ],	SCOPe (2.08)
A	d1sc5a3	All alpha proteins	Sigma2 domain of RNA polymerase sigma factors	Sigma2 domain of RNA polymerase sigma factors	Sigma2 domain of RNA polymerase sigma factors	Sigma factor sigma-28 (FliA)	(Aquifex aeolicus ) [TaxId: 63363 ],	SCOPe (2.08)
B	d1sc5b_	All alpha proteins	Non-globular all-alpha subunits of globular proteins	Anti-sigma factor FlgM	Anti-sigma factor FlgM	Anti-sigma factor FlgM	(Aquifex aeolicus ) [TaxId: 63363 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Sigma factor domain-like	8040789	3000953	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	Sigma2 domain of RNA polymerase sigma factors	8040791	3001393	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	Sigma factor domain-like	8040792	3000953	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	Anti-sigma factor FlgM	8040794	3001384	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	PF04539	e1sc5A1	A: alpha arrays	X: HTH	H: HTH	T: tri-helical	F: PF04539	ECOD (1.6)
A	PF04545	e1sc5A2	A: alpha arrays	X: HTH	H: HTH	T: tri-helical	F: PF04545	ECOD (1.6)
A	PF04542	e1sc5A3	A: alpha complex topology	X: Sigma2 domain-like	H: Sigma2 domain of RNA polymerase sigma factors (From Topology)	T: Sigma2 domain of RNA polymerase sigma factors	F: PF04542	ECOD (1.6)
B	PF04316	e1sc5B1	A: extended segments	X: Anti-sigma factor FlgM (From Topology)	H: Anti-sigma factor FlgM (From Topology)	T: Anti-sigma factor FlgM	F: PF04316	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	1.10.1740.10	Mainly Alpha	Orthogonal Bundle	Rna Polymerase Sigma Factor	Chain: A	CATH (4.3.0)
A	1.20.140.160	Mainly Alpha	Up-down Bundle	Butyryl-CoA Dehydrogenase, subunit A	domain 3	CATH (4.3.0)
B	6.10.140.150	Special	Helix non-globular	Helix Hairpins		CATH (4.3.0)
B	6.10.140.30	Special	Helix non-globular	Helix Hairpins	Anti-sigma-28 factor FlgM	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF04539	Sigma-70 region 3 (Sigma70_r3)	Sigma-70 region 3	-	Family
A	PF04542	Sigma-70 region 2 (Sigma70_r2)	Sigma-70 region 2	Region 2 of sigma-70 is the most conserved region of the entire protein. All members of this class of sigma-factor contain region 2. The high conservation is due to region 2 containing both the -10 promoter recognition helix and the primary core RNA ...	Region 2 of sigma-70 is the most conserved region of the entire protein. All members of this class of sigma-factor contain region 2. The high conservation is due to region 2 containing both the -10 promoter recognition helix and the primary core RNA polymerase binding determinant. The core binding helix, interacts with the clamp domain of the largest polymerase subunit, beta prime [1,2]. The aromatic residues of the recognition helix, found at the C-terminus of this domain are though to mediate strand separation, thereby allowing transcription initiation [1,2].	Domain
A	PF04545	Sigma-70, region 4 (Sigma70_r4)	Sigma-70, region 4	Region 4 of sigma-70 like sigma-factors are involved in binding to the -35 promoter element via a helix-turn-helix motif [1]. Due to the way Pfam works, the threshold has been set artificially high to prevent overlaps with other helix-turn-helix fami ...	Region 4 of sigma-70 like sigma-factors are involved in binding to the -35 promoter element via a helix-turn-helix motif [1]. Due to the way Pfam works, the threshold has been set artificially high to prevent overlaps with other helix-turn-helix families. Therefore there are many false negatives.	Domain
B	PF04316	Anti-sigma-28 factor, FlgM (FlgM)	Anti-sigma-28 factor, FlgM	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	RNA polymerase sigma factor FliA	DNA binding binding organic cyclic compound binding nucleic acid binding protein binding antisigma factor binding DNA-directed 5'-3' RNA polymerase activity 5'-3' RNA polymerase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid RNA polymerase activity transferase activity nucleotidyltransferase activity catalytic activity DNA binding binding organic cyclic compound binding nucleic acid binding protein binding antisigma factor binding DNA-directed 5'-3' RNA polymerase activity 5'-3' RNA polymerase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid RNA polymerase activity transferase activity nucleotidyltransferase activity catalytic activity transferase activity, transferring phosphorus-containing groups transcription regulator activity DNA-binding transcription factor activity sigma factor activity disordered domain specific binding protein domain specific binding	regulation of cellular process cellular biosynthetic process RNA metabolic process regulation of primary metabolic process nucleobase-containing compound metabolic process RNA biosynthetic process nucleic acid biosynthetic process DNA-templated transcription regulation of RNA metabolic process organic substance metabolic process organic substance biosynthetic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process regulation of biosynthetic process regulation of cellular process cellular biosynthetic process RNA metabolic process regulation of primary metabolic process nucleobase-containing compound metabolic process RNA biosynthetic process nucleic acid biosynthetic process DNA-templated transcription regulation of RNA metabolic process organic substance metabolic process organic substance biosynthetic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process regulation of biosynthetic process regulation of biological process cellular metabolic process biological regulation primary metabolic process regulation of cellular metabolic process regulation of macromolecule metabolic process nucleobase-containing compound biosynthetic process gene expression macromolecule biosynthetic process nucleic acid metabolic process regulation of cellular biosynthetic process organic cyclic compound metabolic process regulation of gene expression biosynthetic process organic cyclic compound biosynthetic process metabolic process regulation of macromolecule biosynthetic process cellular process regulation of DNA-templated transcription macromolecule metabolic process regulation of metabolic process DNA-templated transcription initiation	protein-containing complex sigma factor antagonist complex transcription regulator complex
B	anti-sigma factor FlgM	transcription factor binding transcription coregulator binding protein binding binding sigma factor antagonist activity transcription corepressor activity transcription regulator activity transcription coregulator activity protein-macromolecule adaptor activity molecular adaptor activity molecular function inhibitor activity molecular function regulator activity	-	protein-containing complex sigma factor antagonist complex transcription regulator complex

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR007627	RNA polymerase sigma-70 region 2	Domain
A	IPR000943	RNA polymerase sigma-70	Domain
A	IPR012845	RNA polymerase sigma factor, FliA/WhiG	Family
A	IPR013325	RNA polymerase sigma factor, region 2	Homologous Superfamily
A	IPR013324	RNA polymerase sigma factor, region 3/4-like	Homologous Superfamily
A	IPR014284	RNA polymerase sigma-70 like domain	Domain
A	IPR007630	RNA polymerase sigma-70 region 4	Domain
A	IPR007624	RNA polymerase sigma-70 region 3	Domain
B	IPR035890	Anti-sigma-28 factor FlgM superfamily	Homologous Superfamily
B	IPR031316	Anti-sigma-28 factor FlgM, C-terminal	Domain

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.