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6  structures 3843  species 0  interactions 4774  sequences 25  architectures

Family: CobU (PF02283)

Summary: Cobinamide kinase / cobinamide phosphate guanyltransferase

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "Cobalamin biosynthesis". More...

Cobalamin biosynthesis Edit Wikipedia article

PDB 1cbu EBI.jpg
adenosylcobinamide kinase/adenosylcobinamide phosphate guanylyltransferase (cobu) from salmonella typhimurium
Pfam clanCL0023
PDB 1nij EBI.jpg
yjia protein
Pfam clanCL0023
CobW C terminal
PDB 1nij EBI.jpg
yjia protein
PDB 1dah EBI.jpg
dethiobiotin synthetase complexed with 7,8-diamino-nonanoic acid, 5'-adenosyl-methylene-triphosphate, and manganese
Pfam clanCL0023
PDB 1sr8 EBI.jpg
structural genomics, 1.9a crystal structure of cobalamin biosynthesis protein (cbid) from archaeoglobus fulgidus
CbiG N terminus
CbiG central region
CbiG C terminus
Pfam clanCL0315
OPM superfamily134
OPM protein4m58
PDB 1tjn EBI.jpg
crystal structure of hypothetical protein af0721 from archaeoglobus fulgidus
Pfam clanCL0043

In molecular biology, cobalamin biosynthesis is the synthesis of cobalamin (vitamin B12).


Cobalamin (vitamin B12) is a structurally complex cofactor, consisting of a modified tetrapyrrole with a centrally chelated cobalt. Cobalamin is usually found in one of two biologically active forms: methylcobalamin and adenosylcobalamin. Most prokaryotes, as well as animals, have cobalamin-dependent enzymes, whereas plants and fungi do not appear to use it. In bacteria and archaea, these enzymes include methionine synthase, ribonucleotide reductase, glutamate and methylmalonyl-CoA mutases, ethanolamine ammonia-lyase, and diol dehydratase.[1] In certain mammals, cobalamin is obtained through the diet, and is required for methionine synthase and methylmalonyl-CoA mutase.[2]

Pathways of cobalamin biosynthesis

There are at least two distinct cobalamin biosynthetic pathways in bacteria:[3]

Either pathway can be divided into two parts:

  • Corrin ring synthesis (differs in aerobic and anaerobic pathways)
  • Adenosylation of corrin ring, attachment of aminopropanol arm, and assembly of the nucleotide loop (common to both pathways).[7]

Proteins involved in cobalamin biosynthesis

There are about 30 enzymes involved in either pathway, where those involved in the aerobic pathway are prefixed Cob and those of the anaerobic pathway Cbi. Several of these enzymes are pathway-specific: CbiD, CbiG, and CbiK are specific to the anaerobic route of S. typhimurium, whereas CobE, CobF, CobG, CobN, CobS, CobT, and CobW are unique to the aerobic pathway of P. denitrificans.


The CbiB or CobD protein converts cobyric acid to cobinamide by the addition of aminopropanol on the F carboxylic group. It is part of the cob operon.[8]


Aerobic cobalt chelatase consists of three subunits, CobT, CobN and CobS. Cobalamin (vitamin B12) can be complexed with metal via the ATP-dependent reactions (aerobic pathway) (e.g., in P. denitrificans) or via ATP-independent reactions (anaerobic pathway) (e.g., in Salmonella typhimurium).[9][10] The corresponding cobalt chelatases are not homologous. However, aerobic cobalt chelatase subunits CobN and CobS are homologous to Mg-chelatase subunits BchH and BchI, respectively.[10] CobT, too, has been found to be remotely related to the third subunit of Mg-chelatase, BchD (involved in bacteriochlorophyll synthesis, e.g., in Rhodobacter capsulatus).[10]

The CobS protein is a cobalamin-5-phosphate synthase that catyalzes the reactions:

  • Adenosylcobinamide-GDP + alpha-ribazole-5'-P = adenosylcobalamin-5'-phosphate + GMP
  • Adenosylcobinamide-GDP + alpha-ribazole = adenosylcobalamin + GMP

The protein product from these catalyses is associated with a large complex of proteins and is induced by cobinamide. CobS is involved in part III of cobalamin biosynthesis, one of the late steps in adenosylcobalamin synthesis that, together with CobU, CobT, and CobC proteins, defines the nucleotide loop assembly pathway.[11][12]


CobU proteins are bifunctional cobalbumin biosynthesis enzymes which display cobinamide kinase and cobinamide phosphate guanyltransferase activity. The crystal structure of the enzyme reveals the molecule to be a trimer with a propeller-like shape.[13]


CobW proteins are generally found proximal to the trimeric cobaltochelatase subunit CobN, which is essential for vitamin B12 (cobalamin) biosynthesis.[1] They contain a P-loop nucleotide-binding loop in the N-terminal domain and a histidine-rich region in the C-terminal portion suggesting a role in metal binding, possibly as an intermediary between the cobalt transport and chelation systems. CobW might be involved in cobalt reduction leading to cobalt(I) corrinoids. CobW-like proteins include P47K, a Pseudomonas chlororaphis protein needed for nitrile hydratase expression,[14] and urease accessory protein UreG, which acts as a chaperone in the activation of urease upon insertion of nickel into the active site.[15]


The CbiA family of proteins consists of various cobyrinic acid a,c-diamide synthases. These include CbiA and CbiP from Salmonella typhimurium.,[16] and CobQ from Rhodobacter capsulatus.[17] These amidases catalyse amidations to various side chains of hydrogenobyrinic acid or cobyrinic acid a,c-diamide in the biosynthesis of cobalamin (vitamin B12) from uroporphyrinogen III.[16]


CbiD is an essential protein for cobalamin biosynthesis in both Salmonella typhimurium and Bacillus megaterium. A deletion mutant of CbiD suggests that this enzyme is involved in C-1 methylation and deacylation reactions required during the ring contraction process in the anaerobic pathway to cobalamin (similar role as CobF).[18] The CbiD protein has a putative S-AdoMet binding site.[19] CbiD has no counterpart in the aerobic pathway.


CbiG proteins are specific for anaerobic cobalamin biosynthesis. CbiG, which shows homology with CobE of the aerobic pathway, participates in the conversion of cobalt-precorrin 5 into cobalt-precorrin 6.[20] CbiG is responsible for the opening of the delta-lactone ring and extrusion of the C2-unit.[21] The aerobic pathway uses molecular oxygen to trigger the events at C-20 leading to contraction and expulsion of the C2-unit as acetic acid from a metal-free intermediate, whereas the anaerobic route involves the internal delivery of oxygen from a carboxylic acid terminus to C-20 followed by extrusion of the C2-unit as acetaldehyde, using cobalt complexes as substrates.[21]


The CbiJ family of proteins includes the CobK and CbiJ precorrin-6x reductases EC In the aerobic pathway, CobK catalyses the reduction of the macrocycle of precorrin-6X to produce precorrin-6Y; while in the anaerobic pathway CbiJ catalyses the reduction of the macrocycle of cobalt-precorrin-6X into cobalt-precorrin-6Y.[22][23]


CbiM is a transmembrane cobalamin transporter.


The cobalt transport protein CbiN is part of the active cobalt transport system involved in uptake of cobalt into the cell involved with cobalamin biosynthesis (vitamin B12). It has been suggested that CbiN may function as the periplasmic binding protein component of the active cobalt transport system.[17]


The CbiQ family consists of various cobalt transport proteins Most of which are found in Cobalamin (Vitamin B12) biosynthesis operons. In Salmonella the cbiN cbiQ (product CbiQ in this family) and cbiO are likely to form an active cobalt transport system.[24]


The CbiX protein functions as a cobalt-chelatase in the anaerobic biosynthesis of cobalamin. It catalyses the insertion of cobalt into sirohydrochlorin. The structure of CbiX from Archaeoglobus fulgidus consists of a central mixed beta-sheet flanked by four alpha-helices, although it is about half the size of other Class II tetrapyrrole chelatases.[25] The CbiX proteins found in archaea appear to be shorter than those found in eubacteria.[26]


The CbiZ family of proteins includes CbiZ, which is involved in the salvage pathway of cobinamide in archaea. Archaea convert adenosylcobinamide (AdoCbi) into adenosylcobinamide phosphate (AdoCbi-P) in two steps. First, the amidohydrolase activity of CbiZ cleaves off the aminopropanol moiety of AdoCbi yielding adenosylcobyric acid (AdoCby); second, AdoCby is converted into AdoCbi-P by the action of adenosylcobinamide-phosphate synthase (CbiB). Adenosylcobyric acid is an intermediate of the de novo coenzyme B12 biosynthetic route.[27]


  1. ^ a b Rodionov DA, Vitreschak AG, Mironov AA, Gelfand MS (October 2003). "Comparative genomics of the vitamin B12 metabolism and regulation in prokaryotes". J. Biol. Chem. 278 (42): 41148–59. doi:10.1074/jbc.M305837200. PMID 12869542.
  2. ^ Banerjee R (April 2006). "B12 trafficking in mammals: A for coenzyme escort service". ACS Chem. Biol. 1 (3): 149–59. doi:10.1021/cb6001174. PMID 17163662.
  3. ^ Roessner CA, Santander PJ, Scott AI (2001). Multiple biosynthetic pathways for vitamin B12: variations on a central theme. Vitam. Horm. Vitamins & Hormones. 61. pp. 267–97. doi:10.1016/s0083-6729(01)61009-4. ISBN 9780127098616. PMID 11153269.
  4. ^ Heldt D, Lawrence AD, Lindenmeyer M, Deery E, Heathcote P, Rigby SE, Warren MJ (August 2005). "Aerobic synthesis of vitamin B12: ring contraction and cobalt chelation". Biochem. Soc. Trans. 33 (Pt 4): 815–9. doi:10.1042/BST0330815. PMID 16042605.
  5. ^ Roessner CA, Huang KX, Warren MJ, Raux E, Scott AI (June 2002). "Isolation and characterization of 14 additional genes specifying the anaerobic biosynthesis of cobalamin (vitamin B12) in Propionibacterium freudenreichii (P. shermanii)". Microbiology. 148 (Pt 6): 1845–53. doi:10.1099/00221287-148-6-1845. PMID 12055304.
  6. ^ Moore, Simon J.; Lawrence, Andrew D.; Biedendieck, Rebekka; Deery, Evelyne; Frank, Stefanie; Howard, Mark J.; Rigby, Stephen E. J.; Warren, Martin J. (2013-09-10). "Elucidation of the anaerobic pathway for the corrin component of cobalamin (vitamin B12)". Proceedings of the National Academy of Sciences. 110 (37): 14906–14911. doi:10.1073/pnas.1308098110. ISSN 0027-8424. PMC 3773766. PMID 23922391.
  7. ^ Raux E, Schubert HL, Warren MJ (December 2000). "Biosynthesis of cobalamin (vitamin B12): a bacterial conundrum". Cell. Mol. Life Sci. 57 (13–14): 1880–93. doi:10.1007/PL00000670. PMID 11215515.
  8. ^ Woodson JD, Zayas CL, Escalante-Semerena JC (December 2003). "A new pathway for salvaging the coenzyme B12 precursor cobinamide in archaea requires cobinamide-phosphate synthase (CbiB) enzyme activity". J. Bacteriol. 185 (24): 7193–201. doi:10.1128/jb.185.24.7193-7201.2003. PMC 296239. PMID 14645280.
  9. ^ Roth JR, Lawrence JG, Bobik TA (1996). "Cobalamin (coenzyme B12): synthesis and biological significance". Annu. Rev. Microbiol. 50: 137–81. doi:10.1146/annurev.micro.50.1.137. PMID 8905078.
  10. ^ a b c Fodje MN, Hansson A, Hansson M, Olsen JG, Gough S, Willows RD, Al-Karadaghi S (August 2001). "Interplay between an AAA module and an integrin I domain may regulate the function of magnesium chelatase". J. Mol. Biol. 311 (1): 111–22. doi:10.1006/jmbi.2001.4834. PMID 11469861.
  11. ^ Maggio-Hall LA, Escalante-Semerena JC (October 1999). "In vitro synthesis of the nucleotide loop of cobalamin by Salmonella typhimurium enzymes". Proc. Natl. Acad. Sci. U.S.A. 96 (21): 11798–803. doi:10.1073/pnas.96.21.11798. PMC 18366. PMID 10518530.
  12. ^ Maggio-Hall LA, Claas KR, Escalante-Semerena JC (May 2004). "The last step in coenzyme B(12) synthesis is localized to the cell membrane in bacteria and archaea". Microbiology. 150 (Pt 5): 1385–95. doi:10.1099/mic.0.26952-0. PMID 15133100.
  13. ^ Thompson TB, Thomas MG, Escalante-Semerena JC, Rayment I (May 1998). "Three-dimensional structure of adenosylcobinamide kinase/adenosylcobinamide phosphate guanylyltransferase from Salmonella typhimurium determined to 2.3 A resolution". Biochemistry. 37 (21): 7686–95. CiteSeerX doi:10.1021/bi973178f. PMID 9601028.
  14. ^ Hashimoto Y, Nishiyama M, Horinouchi S, Beppu T (October 1994). "Nitrile hydratase gene from Rhodococcus sp. N-774 requirement for its downstream region for efficient expression". Biosci. Biotechnol. Biochem. 58 (10): 1859–65. doi:10.1271/bbb.58.1859. PMID 7765511.
  15. ^ Zambelli B, Musiani F, Savini M, Tucker P, Ciurli S (March 2007). "Biochemical studies on Mycobacterium tuberculosis UreG and comparative modeling reveal structural and functional conservation among the bacterial UreG family". Biochemistry. 46 (11): 3171–82. doi:10.1021/bi6024676. PMID 17309280.
  16. ^ a b Pollich M, Klug G (August 1995). "Identification and sequence analysis of genes involved in late steps in cobalamin (vitamin B12) synthesis in Rhodobacter capsulatus". J. Bacteriol. 177 (15): 4481–7. doi:10.1128/jb.177.15.4481-4487.1995. PMC 177200. PMID 7635831.
  17. ^ a b Roth JR, Lawrence JG, Rubenfield M, Kieffer-Higgins S, Church GM (June 1993). "Characterization of the cobalamin (vitamin B12) biosynthetic genes of Salmonella typhimurium". J. Bacteriol. 175 (11): 3303–16. doi:10.1128/jb.175.11.3303-3316.1993. PMC 204727. PMID 8501034.
  18. ^ Roessner CA, Williams HJ, Scott AI (April 2005). "Genetically engineered production of 1-desmethylcobyrinic acid, 1-desmethylcobyrinic acid a,c-diamide, and cobyrinic acid a,c-diamide in Escherichia coli implies a role for CbiD in C-1 methylation in the anaerobic pathway to cobalamin". J. Biol. Chem. 280 (17): 16748–53. doi:10.1074/jbc.M501805200. PMID 15741157.
  19. ^ Raux E, Lanois A, Warren MJ, Rambach A, Thermes C (October 1998). "Cobalamin (vitamin B12) biosynthesis: identification and characterization of a Bacillus megaterium cobI operon". Biochem. J. 335 (1): 159–66. doi:10.1042/bj3350159. PMC 1219764. PMID 9742225.
  20. ^ Scott AI, Roessner CA (August 2002). "Biosynthesis of cobalamin (vitamin B(12))". Biochem. Soc. Trans. 30 (4): 613–20. doi:10.1042/bst0300613. PMID 12196148.
  21. ^ a b Kajiwara Y, Santander PJ, Roessner CA, Pérez LM, Scott AI (August 2006). "Genetically engineered synthesis and structural characterization of cobalt-precorrin 5A and -5B, two new intermediates on the anaerobic pathway to vitamin B12: definition of the roles of the CbiF and CbiG enzymes". J. Am. Chem. Soc. 128 (30): 9971–8. doi:10.1021/ja062940a. PMID 16866557.
  22. ^ Kim W, Major TA, Whitman WB (December 2005). "Role of the precorrin 6-X reductase gene in cobamide biosynthesis in Methanococcus maripaludis". Archaea. 1 (6): 375–84. doi:10.1155/2005/903614. PMC 2685584. PMID 16243778.
  23. ^ Shearer N, Hinsley AP, Van Spanning RJ, Spiro S (November 1999). "Anaerobic growth of Paracoccus denitrificans requires cobalamin: characterization of cobK and cobJ genes". J. Bacteriol. 181 (22): 6907–13. PMC 94164. PMID 10559155.
  24. ^ Roth, J. R.; Lawrence, J. G.; Rubenfield, M.; Kieffer-Higgins, S.; Church, G. M. (1993). "Characterization of the cobalamin (vitamin B12) biosynthetic genes of Salmonella typhimurium". Journal of Bacteriology. 175 (11): 3303–3316. doi:10.1128/jb.175.11.3303-3316.1993. PMC 204727. PMID 8501034.
  25. ^ Yin J, Xu LX, Cherney MM, Raux-Deery E, Bindley AA, Savchenko A, Walker JR, Cuff ME, Warren MJ, James MN (March 2006). "Crystal structure of the vitamin B12 biosynthetic cobaltochelatase, CbiXS, from Archaeoglobus fulgidus". J. Struct. Funct. Genomics. 7 (1): 37–50. doi:10.1007/s10969-006-9008-x. PMID 16835730.
  26. ^ Brindley AA, Raux E, Leech HK, Schubert HL, Warren MJ (June 2003). "A story of chelatase evolution: identification and characterization of a small 13-15-kDa "ancestral" cobaltochelatase (CbiXS) in the archaea". J. Biol. Chem. 278 (25): 22388–95. doi:10.1074/jbc.M302468200. PMID 12686546.
  27. ^ Woodson JD, Escalante-Semerena JC (March 2004). "CbiZ, an amidohydrolase enzyme required for salvaging the coenzyme B12 precursor cobinamide in archaea". Proc. Natl. Acad. Sci. U.S.A. 101 (10): 3591–6. doi:10.1073/pnas.0305939101. PMC 373507. PMID 14990804.
This article incorporates text from the public domain Pfam and InterPro: IPR004485
This article incorporates text from the public domain Pfam and InterPro: IPR003805
This article incorporates text from the public domain Pfam and InterPro: IPR006538
This article incorporates text from the public domain Pfam and InterPro: IPR003203
This article incorporates text from the public domain Pfam and InterPro: IPR003495
This article incorporates text from the public domain Pfam and InterPro: IPR011629
This article incorporates text from the public domain Pfam and InterPro: IPR002586
This article incorporates text from the public domain Pfam and InterPro: IPR002748
This article incorporates text from the public domain Pfam and InterPro: IPR002750
This article incorporates text from the public domain Pfam and InterPro: IPR003723
This article incorporates text from the public domain Pfam and InterPro: IPR002751
This article incorporates text from the public domain Pfam and InterPro: IPR003705
This article incorporates text from the public domain Pfam and InterPro: IPR003339
This article incorporates text from the public domain Pfam and InterPro: IPR002762
This article incorporates text from the public domain Pfam and InterPro: IPR002808

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Cobinamide kinase / cobinamide phosphate guanyltransferase Provide feedback

This family is composed of a group of bifunctional cobalamin biosynthesis enzymes which display cobinamide kinase and cobinamide phosphate guanyltransferase activity. The crystal structure of the enzyme reveals the molecule to be a trimer with a propeller-like shape [1].

Literature references

  1. Thompson TB, Thomas MG, Escalante-Semerena JC, Rayment I; , Biochemistry 1998;37:7686-7695.: Three-dimensional structure of adenosylcobinamide kinase/adenosylcobinamide phosphate guanylyltransferase from Salmonella typhimurium determined to 2.3 A resolution,. PUBMED:9601028 EPMC:9601028

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External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR003203

This family is composed of a group of bifunctional cobalbumin biosynthesis enzymes which display cobinamide kinase and cobinamide phosphate guanyltransferase activity. The crystal structure of the enzyme reveals the molecule to be a trimer with a propeller-like shape [ PUBMED:9601028 ].

Gene Ontology

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Domain organisation

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Pfam Clan

This family is a member of clan P-loop_NTPase (CL0023), which has the following description:

AAA family proteins often perform chaperone-like functions that assist in the assembly, operation, or disassembly of protein complexes [2].

The clan contains the following 243 members:

6PF2K AAA AAA-ATPase_like AAA_10 AAA_11 AAA_12 AAA_13 AAA_14 AAA_15 AAA_16 AAA_17 AAA_18 AAA_19 AAA_2 AAA_21 AAA_22 AAA_23 AAA_24 AAA_25 AAA_26 AAA_27 AAA_28 AAA_29 AAA_3 AAA_30 AAA_31 AAA_32 AAA_33 AAA_34 AAA_35 AAA_5 AAA_6 AAA_7 AAA_8 AAA_9 AAA_PrkA ABC_ATPase ABC_tran ABC_tran_Xtn Adeno_IVa2 Adenylsucc_synt ADK AFG1_ATPase AIG1 APS_kinase Arf ArsA_ATPase ATP-synt_ab ATP_bind_1 ATP_bind_2 ATPase ATPase_2 Bac_DnaA BCA_ABC_TP_C Beta-Casp bpMoxR Cas_Csn2 Cas_St_Csn2 CbiA CBP_BcsQ CDC73_C CENP-M CFTR_R CLP1_P CMS1 CoaE CobA_CobO_BtuR CobU cobW CPT CSM2 CTP_synth_N Cytidylate_kin Cytidylate_kin2 DAP3 DBINO DEAD DEAD_2 DLIC DNA_pack_C DNA_pack_N DNA_pol3_delta DNA_pol3_delta2 DnaB_C dNK DO-GTPase1 DO-GTPase2 DUF1611 DUF1726 DUF2075 DUF2326 DUF2478 DUF257 DUF2791 DUF2813 DUF3584 DUF463 DUF5906 DUF6079 DUF815 DUF853 DUF87 DUF927 Dynamin_N Dynein_heavy Elong_Iki1 ELP6 ERCC3_RAD25_C Exonuc_V_gamma FeoB_N Fer4_NifH Flavi_DEAD FTHFS FtsK_SpoIIIE G-alpha Gal-3-0_sulfotr GBP GBP_C GTP_EFTU Gtr1_RagA Guanylate_kin GvpD HDA2-3 Helicase_C Helicase_C_2 Helicase_C_4 Helicase_RecD Herpes_Helicase Herpes_ori_bp Herpes_TK HSA HydF_dimer HydF_tetramer Hydin_ADK IIGP IPPT IPT iSTAND IstB_IS21 KAP_NTPase KdpD Kinase-PPPase Kinesin KTI12 LAP1C Lon_2 LpxK MCM MeaB MEDS Mg_chelatase Microtub_bd MipZ MMR_HSR1 MMR_HSR1_C MobB MukB Mur_ligase_M MutS_V Myosin_head NACHT NAT_N NB-ARC NOG1 NTPase_1 NTPase_P4 OPA1_C ORC3_N P-loop_TraG ParA Parvo_NS1 PAXNEB PduV-EutP PhoH PIF1 Ploopntkinase1 Ploopntkinase2 Ploopntkinase3 Podovirus_Gp16 Polyoma_lg_T_C Pox_A32 PPK2 PPV_E1_C PRK PSY3 Rad17 Rad51 Ras RecA ResIII RHD3 RhoGAP_pG1_pG2 RHSP RNA12 RNA_helicase Roc RsgA_GTPase RuvB_N SbcCD_C SecA_DEAD Septin Sigma54_activ_2 Sigma54_activat SKI SMC_N SNF2-rel_dom Spore_III_AA Spore_IV_A SRP54 SRPRB SulA Sulfotransfer_1 Sulfotransfer_2 Sulfotransfer_3 Sulfotransfer_4 Sulfotransfer_5 Sulphotransf SWI2_SNF2 T2SSE T4SS-DNA_transf Terminase_1 Terminase_3 Terminase_6N Terminase_GpA Thymidylate_kin TIP49 TK TniB Torsin TraG-D_C tRNA_lig_kinase TrwB_AAD_bind TsaE UvrB UvrD-helicase UvrD_C UvrD_C_2 Viral_helicase1 VirC1 VirE YqeC Zeta_toxin Zot


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Curation and family details

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Curation View help on the curation process

Seed source: Pfam-B_7022 (release 5.2)
Previous IDs: COBU;
Type: Domain
Sequence Ontology: SO:0000417
Author: Mian N , Bateman A
Number in seed: 112
Number in full: 4774
Average length of the domain: 161.60 aa
Average identity of full alignment: 33 %
Average coverage of the sequence by the domain: 80.03 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 21.5 21.5
Trusted cut-off 21.5 21.5
Noise cut-off 21.4 21.4
Model length: 170
Family (HMM) version: 18
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Archea Archea Eukaryota Eukaryota
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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 CobU domain has been found. There are 6 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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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
O53676 View 3D Structure Click here
P0AE76 View 3D Structure Click here