Summary: Chitinase A, N-terminal domain
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Chitinase A N-terminal domain Edit Wikipedia article
crystal structure of chitinase a from s. marcescens at 1.55 angstroms
In molecular biology, the chitinase A N-terminal domain is found at the N-terminus of a number of bacterial chitinases and similar viral proteins. It is organised into a fibronectin III module domain-like fold, comprising only beta strands. Its function is not known, but it may be involved in interaction with the enzyme substrate, chitin. It is separated by a hinge region from the catalytic domain; this hinge region is probably mobile, allowing the N-terminal domain to have different relative positions in solution.
- Perrakis A, Tews I, Dauter Z, Oppenheim AB, Chet I, Wilson KS, Vorgias CE (December 1994). "Crystal structure of a bacterial chitinase at 2.3 A resolution". Structure. 2 (12): 1169–80. doi:10.1016/s0969-2126(94)00119-7. PMID 7704527.
- Perrakis A, Ouzounis C, Wilson KS (1997). "Evolution of immunoglobulin-like modules in chitinases: their structural flexibility and functional implications". Fold Des. 2 (5): 291–4. doi:10.1016/s1359-0278(97)00040-0. PMID 9377712.
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Chitinase A, N-terminal domain Provide feedback
This domain is found in a number of bacterial chitinases and similar viral proteins. It is organised into a fibronectin III module domain-like fold, comprising only beta strands. Its function is not known, but it may be involved in interaction with the enzyme substrate, chitin [1,2]. It is separated by a hinge region from the catalytic domain (PF00704); this hinge region is probably mobile, allowing the N-terminal domain to have different relative positions in solution .
Perrakis A, Ouzounis C, Wilson KS; , Fold Des 1997;2:291-294.: Evolution of immunoglobulin-like modules in chitinases: their structural flexibility and functional implications. PUBMED:9377712 EPMC:9377712
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR013540
This domain is found in a number of bacterial chitinases and similar viral proteins. It is organised into a fibronectin III module domain-like fold, comprising only beta strands. Its function is not known, but it may be involved in interaction with the enzyme substrate, chitin [ PUBMED:7704527 , PUBMED:9377712 ]. It is separated by a hinge region from the catalytic domain ( INTERPRO ); this hinge region is probably mobile, allowing the N-terminal domain to have different relative positions in solution [ PUBMED:7704527 ].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||chitinase activity (GO:0004568)|
|Biological process||chitin catabolic process (GO:0006032)|
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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Gladomain, followed by two consecutive
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This clan includes a diverse range of domains that have an Ig-like fold and appear to be distantly related to each other. The clan includes: PKD domains, cadherins and several families of bacterial Ig-like domains as well as viral tail fibre proteins. it also includes several Fibronectin type III domain-containing families.
The clan contains the following 257 members:A2M A2M_BRD A2M_recep AA9 Adeno_GP19K AlcCBM31 Alpha-amylase_N Alpha_adaptinC2 Alpha_E2_glycop Anth_Ig aRib Arylsulfotran_N ASF1_hist_chap ATG19 BACON BACON_2 BatD BIg21 Big_1 Big_10 Big_11 Big_12 Big_13 Big_14 Big_15 Big_2 Big_3 Big_3_2 Big_3_3 Big_3_4 Big_3_5 Big_4 Big_5 Big_6 Big_7 Big_8 Big_9 Bile_Hydr_Trans BiPBP_C bMG1 bMG10 bMG3 bMG5 bMG6 BslA BsuPI Cadherin Cadherin-like Cadherin_2 Cadherin_3 Cadherin_4 Cadherin_5 Cadherin_pro CagX Calx-beta Candida_ALS_N CARDB CBM39 CBM_X2 CD45 CelD_N Ceramidse_alk_C CHB_HEX_C CHB_HEX_C_1 ChitinaseA_N ChiW_Ig_like Chlam_OMP6 CHU_C Coatamer_beta_C COP-gamma_platf CopC CshA_repeat Cyc-maltodext_N Cytomega_US3 DBB DsbC DUF11 DUF1410 DUF1425 DUF2271 DUF3244 DUF3458 DUF3501 DUF3823_C DUF3859 DUF4165 DUF4179 DUF4426 DUF4469 DUF4625 DUF4784_N DUF4879 DUF4959 DUF4982 DUF4998 DUF5001 DUF5008 DUF5011 DUF5060 DUF5065 DUF5103 DUF5115 DUF525 DUF5643 DUF6383 DUF6595 DUF916 EB_dh ECD Enterochelin_N EpoR_lig-bind ERAP1_C EstA_Ig_like Expansin_C Filamin FixG_C Flavi_glycop_C FlgD_ig fn3 Fn3-like fn3_2 fn3_4 fn3_5 fn3_6 FN3_7 Fn3_assoc fn3_PAP GBS_Bsp-like GlgE_dom_N_S Glucodextran_B Glyco_hydro2_C5 Glyco_hydro_2 Gmad2 GMP_PDE_delta GO-like_E_set GspA_SrpA_N Hanta_G1 He_PIG HECW_N HemeBinding_Shp Hemocyanin_C Herpes_BLLF1 HYR IalB IFNGR1 Ig_GlcNase Ig_mannosidase IL12p40_C Il13Ra_Ig IL17R_fnIII_D1 IL17R_fnIII_D2 IL2RB_N1 IL3Ra_N IL4Ra_N IL6Ra-bind Inhibitor_I42 Inhibitor_I71 InlK_D3 Integrin_alpha2 Interfer-bind Invasin_D3 IRK_C IrmA Iron_transport Kre9_KNH LacZ_4 LEA_2 Lep_receptor_Ig LIFR_D2 LIFR_N Lipase_bact_N LodA_N LPMO_10 LRR_adjacent LTD MALT1_Ig Mannosidase_ig MetallophosC MG1 MG2 MG3 MG4 Mo-co_dimer N_BRCA1_IG Na_K-ATPase NAR2 NDNF NDNF_C NEAT Neocarzinostat Neurexophilin NPCBM_assoc Omp28 PapD_C PBP-Tp47_c Peptidase_C25_C Phlebo_G2_C PhoD_N PKD PKD_2 PKD_3 PKD_4 PKD_5 PKD_6 Por_Secre_tail Pox_vIL-18BP Psg1 PTP_tm Pullulanase_N2 Pur_ac_phosph_N Qn_am_d_aIII Qn_am_d_aIV RabGGT_insert Reeler REJ RET_CLD1 RET_CLD3 RET_CLD4 RGI_lyase RHD_dimer Rho_GDI Rib RibLong SCAB-Ig SKICH SLAM SoxZ SprB SusE SVA SWM_repeat T2SS-T3SS_pil_N Tafi-CsgC TarS_C1 TcA_RBD TcfC TIG TIG_2 TIG_plexin TIG_SUH Tissue_fac Top6b_C TPPII TQ Transglut_C Transglut_N TRAP_beta TraQ_transposon UL16 Velvet WIF Wzt_C Y_Y_Y YBD YscW ZirS_C Zona_pellucida
We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...
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We make a range of alignments for each Pfam-A family:
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- alignment generated by searching the UniProtKB sequence database using the family HMM
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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
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|Seed source:||Pfam-B_1049 (release 18.0)|
|Number in seed:||7|
|Number in full:||275|
|Average length of the domain:||111.30 aa|
|Average identity of full alignment:||28 %|
|Average coverage of the sequence by the domain:||12.38 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||13|
|Download:||download the raw HMM for this family|
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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the More....
This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.
How the sunburst is generated
The tree is built by considering the taxonomic lineage of each sequence that has a match to this family. For each node in the resulting tree, we draw an arc in the sunburst. The radius of the arc, its distance from the root node at the centre of the sunburst, shows the taxonomic level ("superkingdom", "kingdom", etc). The length of the arc represents either the number of sequences represented at a given level, or the number of species that are found beneath the node in the tree. The weighting scheme can be changed using the sunburst controls.
In order to reduce the complexity of the representation, we reduce the number of taxonomic levels that we show. We consider only the following eight major taxonomic levels:
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Segments of the tree are coloured approximately according to their superkingdom. For example, archeal branches are coloured with shades of orange, eukaryotes in shades of purple, etc. The colour assignments are shown under the sunburst controls. Where space allows, the name of the taxonomic level will be written on the arc itself.
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There are some situations that the sunburst tree cannot easily handle and for which we have work-arounds in place.
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Some species in the taxonomic tree may not have one or more of the main eight levels that we display. For example, Bos taurus is not assigned an order in the NCBI taxonomic tree. In such cases we mark the omitted level with, for example, "No order", in both the tooltip and the lineage summary.
Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
So that these nodes are not simply omitted from the sunburst tree, we group them together in a separate branch (or segment of the sunburst tree). Since we cannot determine the lineage for these unmapped species, we show all levels between the superkingdom and the species as "uncategorised".
Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
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For large species trees, you may see blank regions in the outer layers of the sunburst. These occur when there are large numbers of arcs to be drawn in a small space. If an arc is less than approximately one pixel wide, it will not be drawn and the space will be left blank. You may still be able to get some information about the species in that region by moving your mouse across the area, but since each arc will be very small, it will be difficult to accurately locate a particular species.
The tree shows the occurrence of this domain across different species. More...
We show the species tree in one of two ways. For smaller trees we try to show an interactive representation, which allows you to select specific nodes in the tree and view them as an alignment or as a set of Pfam domain graphics.
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
We also count the number of unique sequences on which each domain is found, which is shown in green. Note that a domain may appear multiple times on the same sequence, leading to the difference between these two numbers.
Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.
We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the ChitinaseA_N domain has been found. There are 47 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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