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Cytochrome b5-like heme/steroid binding domain superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Alpha and beta proteins (a+b) [ 53931] (376)
Fold:   Cytochrome b5-like heme/steroid binding domain [ 55855]
Superfamily:   Cytochrome b5-like heme/steroid binding domain [ 55856] (2)
Families:   Cytochrome b5 [ 55857] (4)
  Steroid-binding domain [ 103222]


Superfamily statistics
Genomes (662) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 8,888 27,863 34
Proteins 8,712 27,400 34


Functional annotation
General category Metabolism
Detailed category E- transfer

Document:
Function annotation of SCOP domain superfamilies

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEO levelAnnotation (direct or inherited)
Enzyme Commission (EC)Oxidoreductases0Least InformativeDirect
Enzyme Commission (EC)Acting on a sulfur group of donors0.01363Moderately InformativeInherited
Enzyme Commission (EC)Acting on NADH or NADPH0.0902Moderately InformativeInherited
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor0InformativeDirect
Enzyme Commission (EC)Nitrate reductase (NADH)0Highly InformativeDirect
Enzyme Commission (EC)Sulfite oxidase0Highly InformativeDirect
Enzyme Commission (EC)With a heme protein as acceptor0.00000000000002642Highly InformativeDirect
Enzyme Commission (EC)Nitrate reductase (NADPH)0.0000000004944Highly InformativeDirect

Document: EC annotation of SCOP domains

Human Phenotype (HP)

(show details)
HP termFDR (all)SDHP levelAnnotation (direct or inherited)
Phenotypic Abnormality (PA)Abnormality of the genitourinary system0Least InformativeDirect
Phenotypic Abnormality (PA)Abnormality of the head0Least InformativeDirect
Phenotypic Abnormality (PA)Abnormality of the eye0Least InformativeDirect
Phenotypic Abnormality (PA)Abnormality of the musculature0Least InformativeDirect
Phenotypic Abnormality (PA)Abnormality of nervous system physiology0Least InformativeDirect
Phenotypic Abnormality (PA)Abnormal muscle tone0Moderately InformativeDirect
Phenotypic Abnormality (PA)Abnormality of central motor function0Moderately InformativeDirect
Phenotypic Abnormality (PA)Neurodevelopmental abnormality0Moderately InformativeDirect
Phenotypic Abnormality (PA)Abnormality of movement0Moderately InformativeDirect
Phenotypic Abnormality (PA)Seizures0InformativeDirect
Phenotypic Abnormality (PA)Involuntary movements0InformativeDirect

Document: HP annotation of SCOP domains

Worm Phenotype (WP)

(show details) Document: WP annotation of SCOP domains

Yeast Phenotype (YP)

(show details) Document: YP annotation of SCOP domains

Xenopus Anatomy (XA)

(show details)
XA termFDR (all)SDXA levelAnnotation (direct or inherited)
Xenopus ANatomical entity (XAN)urogenital system0Least InformativeDirect
Xenopus ANatomical entity (XAN)head0Least InformativeDirect
Xenopus ANatomical entity (XAN)cavitated compound organ0Least InformativeDirect
Xenopus DEvelopment stage (XDE)post-embryonic stage0Least InformativeDirect
Xenopus DEvelopment stage (XDE)climax stage0Moderately InformativeDirect

Document: XA annotation of SCOP domains

Arabidopsis Plant Ontology (AP)

(show details) Document: AP annotation of SCOP domains

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEC levelAnnotation (direct or inherited)
Enzyme Commission (EC)Oxidoreductases0Least InformativeDirect
Enzyme Commission (EC)Acting on paired donors, with incorporation or reduction of molecular oxygen. The oxygen incorporate0InformativeDirect
Enzyme Commission (EC)Acting on other nitrogenous compounds as donors0InformativeDirect
Enzyme Commission (EC)Acting on NADH or NADPH0.007842InformativeInherited
Enzyme Commission (EC)Acting on a sulfur group of donors0.1864InformativeInherited
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor0Highly InformativeDirect
Enzyme Commission (EC)With oxygen as acceptor0.00000000000001436Highly InformativeDirect
Enzyme Commission (EC)With a heme protein as acceptor0.00000000000145Highly InformativeDirect

Document: EC annotation of SCOP domains

InterPro annotation
Cross references IPR001199 SSF55856 Protein matches
Abstract Cytochromes b5 are ubiquitous electron transport proteins found in animals, plants and yeasts [PubMed2752049]. The microsomal and mitochondrial variants are membrane-bound, while those from erythrocytes and other animal tissues are water-soluble [PubMed4030743, PubMed8439576].

The 3D structure of bovine cyt b5 is known, the fold belonging to the alpha+beta class, with 5 strands and 5 short helices forming a framework for supporting a central haem group [PubMed1167544]. The cytochrome b5 domain is similar to that of a number of oxidoreductases, such as plant and fungal nitrate reductases, sulphite oxidase, yeast flavocytochrome b2 (L-lactate dehydrogenase) and plant cyt b5/acyl lipid desaturase fusion protein.


InterPro database


PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Human Phenotype (HP) · Worm Phenotype (WP) · Yeast Phenotype (YP) · Xenopus Anatomy (XA) · Arabidopsis Plant Ontology (AP) · Enzyme Commission (EC) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.


Alignments of sequences to 20 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.


Browse and view proteins in genomes which have different domain combinations including a Cytochrome b5-like heme/steroid binding domain domain.


Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.


Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 20 hidden Markov models representing the Cytochrome b5-like heme/steroid binding domain superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.


Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Human Phenotype (HP) · Worm Phenotype (WP) · Yeast Phenotype (YP) · Xenopus Anatomy (XA) · Arabidopsis Plant Ontology (AP) · Enzyme Commission (EC) · Internal database links ]