Powering down the Pfam website
On October 5th, we will start redirecting the traffic from Pfam (pfam.xfam.org) to InterPro (www.ebi.ac.uk/interpro). The Pfam website will be available at legacy.pfam.xfam.org until January 2023, when it will be decommissioned. You can read more about the sunset period in our blog post.

Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
35  structures 1489  species 0  interactions 8422  sequences 114  architectures

Family: 6PF2K (PF01591)

Summary: 6-phosphofructo-2-kinase

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 "6-phosphofructo-2-kinase". More...

6-phosphofructo-2-kinase Edit Wikipedia article

In enzymology, a 6-phosphofructo-2-kinase (EC is an enzyme that catalyzes the chemical reaction

ATP + beta-D-fructose 6-phosphate ADP + beta-D-fructose 2,6-bisphosphate

Thus, the two substrates of this enzyme are ATP and beta-D-fructose 6-phosphate, whereas its two products are ADP and beta-D-fructose 2,6-bisphosphate.

This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The systematic name of this enzyme class is ATP:beta-D-fructose-6-phosphate 2-phosphotransferase. Other names in common use include phosphofructokinase 2, 6-phosphofructose 2-kinase, 6-phosphofructo-2-kinase (phosphorylating), fructose 6-phosphate 2-kinase, and ATP:D-fructose-6-phosphate 2-phosphotransferase. This enzyme participates in fructose and mannose metabolism.

Structural studies

As of late 2007, 8 structures have been solved for this class of enzymes, with PDB accession codes 1BIF, 1K6M, 2AXN, 2BIF, 2DWO, 2DWP, 2I1V, and 3BIF.


Template:Enzyme references

  • Van Schaftingen E, Hers HG (1981). "Phosphofructokinase 2: the enzyme that forms fructose 2,6-bisphosphate from fructose 6-phosphate and ATP". Biochem. Biophys. Res. Commun. 101: 1078–84. PMID 6458291.

External links

The CAS registry number for this enzyme class is Template:CAS registry.

Template:Enzyme links

Gene Ontology (GO) codes

Template:GO code links

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This is the Wikipedia entry entitled "Phosphofructokinase 2". More...

Phosphofructokinase 2 Edit Wikipedia article

converts fructose 6-phosphate to fructose 2,6-bisphosphate

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

6-phosphofructo-2-kinase Provide feedback

This enzyme occurs as a bifunctional enzyme with fructose-2,6-bisphosphatase. The bifunctional enzyme catalyses both the synthesis and degradation of fructose-2,6-bisphosphate, a potent regulator of glycolysis [1]. This enzyme contains a P-loop motif.

Literature references

  1. Hasemann CA, Istvan ES, Uyeda K, Deisenhofer J; , Structure 1996;4:1017-1029.: The crystal structure of the bifunctional enzyme 6-phosphofructo-2- kinase/fructose-2,6-bisphosphatase reveals distinct domain homologies. PUBMED:8805587 EPMC:8805587

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR013079

6-Phosphofructo-2-kinase ( EC , EC ) is a bifunctional enzyme that catalyses both the synthesis and the degradation of fructose-2, 6-bisphosphate. The fructose-2,6-bisphosphatase reaction involves a phosphohistidine intermediate. The catalytic pathway is: ATP + D-fructose 6-phosphate = ADP + D-fructose 2,6-bisphosphate D-fructose 2,6-bisphosphate + H 2 O = 6-fructose 6-phosphate + P i The enzyme is important in the regulation of hepatic carbohydrate metabolism and is found in greatest quantities in the liver, kidney and heart. In mammals, several genes often encode different isoforms, each of which differs in its tissue distribution and enzymatic activity [ PUBMED:9652401 ]. The family described here bears a resemblance to the ATP-driven phospho-fructokinases, however, they share little sequence similarity, although a few residues seem key to their interaction with fructose 6-phosphate [ PUBMED:9753654 ].

This domain forms the N-terminal region of this enzyme, while INTERPRO forms the C-terminal domain.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

Loading domain graphics...

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 245 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 BrxC_BrxD BrxL_ATPase 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 DEAD DEAD_2 divDNAB DLIC DNA_pack_C DNA_pack_N DNA_pol3_delta DNA_pol3_delta2 DnaB_C dNK DO-GTPase1 DO-GTPase2 DUF1611 DUF2075 DUF2326 DUF2478 DUF257 DUF2813 DUF3584 DUF463 DUF4914 DUF5906 DUF6079 DUF815 DUF835 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 GpA_ATPase GpA_nuclease GTP_EFTU Gtr1_RagA Guanylate_kin GvpD_P-loop HDA2-3 Helicase_C Helicase_C_2 Helicase_C_4 Helicase_RecD HerA_C Herpes_Helicase Herpes_ori_bp Herpes_TK HydF_dimer HydF_tetramer Hydin_ADK IIGP IPPT IPT iSTAND IstB_IS21 KAP_NTPase KdpD Kinase-PPPase Kinesin KTI12 LAP1_C 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 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_GTPase RhoGAP_pG1_pG2 RHSP RNA12 RNA_helicase Roc RsgA_GTPase RuvB_N SbcC_Walker_B SecA_DEAD Senescence Septin Sigma54_activ_2 Sigma54_activat SKI SMC_N SNF2-rel_dom SpoIVA_ATPase Spore_III_AA SRP54 SRPRB SulA Sulfotransfer_1 Sulfotransfer_2 Sulfotransfer_3 Sulfotransfer_4 Sulfotransfer_5 Sulphotransf SWI2_SNF2 T2SSE T4SS-DNA_transf TerL_ATPase Terminase_3 Terminase_6N Thymidylate_kin TIP49 TK TmcA_N 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


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...

View options

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.

Representative proteomes UniProt
Jalview View  View  View  View  View  View  View 
HTML View             
PP/heatmap 1            

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

Representative proteomes UniProt

Download options

We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

Representative proteomes UniProt
Raw Stockholm Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download  

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


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.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Pfam-B_717 (release 4.1)
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bateman A
Number in seed: 11
Number in full: 8422
Average length of the domain: 196.6 aa
Average identity of full alignment: 44 %
Average coverage of the sequence by the domain: 41.04 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 27.0 27.0
Trusted cut-off 27.0 27.1
Noise cut-off 26.9 26.9
Model length: 223
Family (HMM) version: 21
Download: download the raw HMM for this family

Species distribution

Sunburst controls


Weight segments by...

Change the size of the sunburst


Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


Align selected sequences to HMM

Generate a FASTA-format file

Clear selection

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Loading sunburst data...

Tree controls


The tree shows the occurrence of this domain across different species. More...


Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.


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 6PF2K domain has been found. There are 35 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.

Loading structure mapping...

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
A0A044RCV3 View 3D Structure Click here
A0A077YZZ1 View 3D Structure Click here
A0A0D2EMU8 View 3D Structure Click here
A0A0D2GAU0 View 3D Structure Click here
A0A0D2GL10 View 3D Structure Click here
A0A0K0E2H3 View 3D Structure Click here
A0A0N4UEV7 View 3D Structure Click here
A0A0R0HIC4 View 3D Structure Click here
A0A0R0HRM7 View 3D Structure Click here
A0A175VQU0 View 3D Structure Click here
A0A175W5B8 View 3D Structure Click here
A0A175WE84 View 3D Structure Click here
A0A1C1C6U3 View 3D Structure Click here
A0A1C1CAM5 View 3D Structure Click here
A0A1C1CQJ1 View 3D Structure Click here
A0A1D6JZG1 View 3D Structure Click here
A0A1D8PCP7 View 3D Structure Click here
A0A1D8PEF9 View 3D Structure Click here
A0A3P7DQM6 View 3D Structure Click here
A0A3P7DU96 View 3D Structure Click here
A0A5S6PBY5 View 3D Structure Click here
A0A5S6PC44 View 3D Structure Click here
A2AR70 View 3D Structure Click here
A4HRW8 View 3D Structure Click here
A4HTA2 View 3D Structure Click here
A4I1W7 View 3D Structure Click here
A7UAK5 View 3D Structure Click here
B4F8N3 View 3D Structure Click here
C0NDG1 View 3D Structure Click here
C0NYB2 View 3D Structure Click here
C0P176 View 3D Structure Click here
C1GNG7 View 3D Structure Click here
C1GXS0 View 3D Structure Click here
C1HB45 View 3D Structure Click here
F1QPT5 View 3D Structure Click here
F1R374 View 3D Structure Click here
F1R8T1 View 3D Structure Click here
F6NXI0 View 3D Structure Click here
F7FKL9 View 3D Structure Click here
G4VSL5 View 3D Structure Click here