Ribbon-helix-helix superfamily

SCOP classification

• Root: SCOP hierarchy in SUPERFAMILY [ 0] (11)
• Class: All alpha proteins [ 46456] (284)
• Fold: Ribbon-helix-helix [ 47597]
• Superfamily: Ribbon-helix-helix [ 47598] (11)
• Families:
  • Arc/Mnt-like phage repressors [ 47599] (2)
  • CopG-like [ 100970] (4)
  • Omega transcriptional repressor [ 100971]
  • Met repressor, MetJ (MetR) [ 100972]
  • NE0241-like [ 140544]
  • SeqA N-terminal domain-like [ 140547]
  • Trafficking protein A-like [ 140550]
  • VCA0319-like [ 140553]
  • VirC2-like [ 158482]
  • PutA pre-N-terminal region-like [ 158485]
  • MJ0366-like [ 158488]

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Superfamily statistics

	Genomes (1,925)	Uniprot 2018_03 genome	PDB chains (SCOP 1.75)
Domains	8,055	63,240	28
Proteins	8,041	63,157	27

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Functional annotation

• General category: Regulation
• Detailed category: DNA-binding

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Enzyme Commission (EC)

Highlighted in gray are those with FDR_all>0.001

	EC term	FDR (all)	IC level	SDEC level	Annotation (direct or inherited)
Enzyme Commission (EC)	Proline dehydrogenase	0	2.35	--	DIRECT
Enzyme Commission (EC)	L-glutamate gamma-semialdehyde dehydrogenase	0	2.35	--	DIRECT
Enzyme Commission (EC)	Oxidoreductases	0	0.6234	Least Informative	DIRECT
Enzyme Commission (EC)	Acting on the aldehyde or oxo group of donors	0	1.42	Informative	DIRECT
Enzyme Commission (EC)	Acting on the CH-NH group of donors	0	1.505	Informative	DIRECT
Enzyme Commission (EC)	With NAD(+) or NADP(+) as acceptor	0	1.806	Highly Informative	DIRECT
Enzyme Commission (EC)	With a quinone or similar compound as acceptor	0	2.107	Highly Informative	DIRECT

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UniProtKB KeyWords (KW)

Highlighted in gray are those with FDR_all>0.001

	KW term	FDR (all)	IC level	SDKW level	Annotation (direct or inherited)
Biological process	Toxin-antitoxin system	0	0.9031	Moderately Informative	DIRECT

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InterPro annotation

• Cross references: IPR010985 SSF47598 Protein matches
• Abstract:

  This entry represents domains with a ribbon-helix-helix core topology consisting of four helices in an open array of two hairpins. Such domains are found in several bacterial and phage repressors, including the Escherichia coli methionine repressor (MetJ), which when combined with S-adenosylmethionine (SAM) represses the expression of the methionine regulon and of enzymes involved in SAM synthesis [1943695]. Other bacterial and phage repressors containing domains with a similar fold include the bacterial plasmid-encoded repressors CopG , the bacterial omega transcription repressor [11733997], and the phage repressors Arc [9927650] and Mnt [7999761]. These repressors are usually obligate dimers, which pair through a single N-terminal strand, and possess a C-terminal helix-turn-helix unit [15808743].

InterPro database

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