SUPERFAMILY 1.75 HMM library and genome assignments server

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Nitrite/Sulfite reductase N-terminal domain-like superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Alpha and beta proteins (a+b) [ 53931] (376)
Fold:   Ferredoxin-like [ 54861] (59)
Superfamily:   Nitrite/Sulfite reductase N-terminal domain-like [ 55124] (2)
Families:   Duplicated SiR/NiR-like domains 1 and 3 [ 55125] (3)
  DsrA/DsrB N-terminal-domain-like [ 160336] (2)


Superfamily statistics
Genomes (1,957) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 6,669 59,023 10
Proteins 4,282 41,174 7


Functional annotation
General category Metabolism
Detailed category Redox

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 donors0Moderately InformativeDirect
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor0InformativeDirect
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor1InformativeInherited
Enzyme Commission (EC)Sulfite reductase (NADPH)0Highly InformativeDirect
Enzyme Commission (EC)Nitrite reductase (NAD(P)H)0.000000000000002328Highly InformativeDirect
Enzyme Commission (EC)With other acceptors0.000383Highly InformativeDirect
Enzyme Commission (EC)With an iron-sulfur protein as acceptor0.0004265Highly InformativeDirect

Document: EC 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 a sulfur group of donors0InformativeDirect
Enzyme Commission (EC)Acting on other nitrogenous compounds as donors0.038InformativeInherited
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor0Highly InformativeDirect
Enzyme Commission (EC)With an iron-sulfur protein as acceptor0.00277Highly InformativeInherited
Enzyme Commission (EC)With NAD(+) or NADP(+) as acceptor1Highly InformativeInherited

Document: EC annotation of SCOP domains

InterPro annotation
Cross references IPR005117 SSF55124 Protein matches
Abstract

Sulphite reductases (SiRs) and related nitrite reductases (NiRs) catalyse the six-electron reduction reactions of sulphite to sulphide, and nitrite to ammonia, respectively. The Escherichia coli SiR enzyme is a complex composed of two proteins, a flavoprotein alpha-component (SiR-FP) and a hemoprotein beta-component (SiR-HP), and has an alpha(8)beta(4) quaternary structure [PubMed10984484]. SiR-FP contains both FAD and FMN, while SiR-HP contains a Fe(4)S(4) cluster coupled to a sirohaem through a cysteine bridge. Electrons are transferred from NADPH to FAD, and on to FMN in SiR-FP, from which they are transferred to the metal centre of SiR-HP, where they reduce the siroheme-bound sulphite.

SiR-HP has a two-fold symmetry, which generates a distinctive three-domain alpha/beta fold that controls assembly and reactivity [PubMed7569952]. This entry describes the ferrodoxin-like (alpha/beta sandwich) domain, which consists of a duplication containing two subdomains of this fold.


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

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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 12 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 Nitrite/Sulfite reductase N-terminal domain-like 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 12 hidden Markov models representing the Nitrite/Sulfite reductase N-terminal domain-like 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) · Enzyme Commission (EC) · Internal database links ]