Summary: YCF9
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YCF9 Provide feedback
This family consists of the hypothetical protein product of the YCF9 gene from chloroplasts and cyanobacteria. These proteins have no known function.
External database links
| PANDIT: | PF01737 |
| Pseudofam: | PF01737 |
| SYSTERS: | Ycf9 |
This tab holds annotation information from the InterPro database.
InterPro entry IPR002644
Oxygenic photosynthesis uses two multi-subunit photosystems (I and II) located in the cell membranes of cyanobacteria and in the thylakoid membranes of chloroplasts in plants and algae. Photosystem II (PSII) has a P680 reaction centre containing chlorophyll 'a' that uses light energy to carry out the oxidation (splitting) of water molecules, and to produce ATP via a proton pump. Photosystem I (PSI) has a P700 reaction centre containing chlorophyll that takes the electron and associated hydrogen donated from PSII to reduce NADP+ to NADPH. Both ATP and NADPH are subsequently used in the light-independent reactions to convert carbon dioxide to glucose using the hydrogen atom extracted from water by PSII, releasing oxygen as a by-product.
PSII is a multisubunit protein-pigment complex containing polypeptides both intrinsic and extrinsic to the photosynthetic membrane [PUBMED:12518057, PUBMED:15100025]. Within the core of the complex, the chlorophyll and beta-carotene pigments are mainly bound to the antenna proteins CP43 (PsbC) and CP47 (PsbB), which pass the excitation energy on to the reaction centre proteins D1 (Qb, PsbA) and D2 (Qa, PsbD) that bind all the redox-active cofactors involved in the energy conversion process. The PSII oxygen-evolving complex (OEC) oxidises water to provide protons for use by PSI, and consists of OEE1 (PsbO), OEE2 (PsbP) and OEE3 (PsbQ). The remaining subunits in PSII are of low molecular weight (less than 10 kDa), and are involved in PSII assembly, stabilisation, dimerisation, and photo-protection [PUBMED:14871485].
This family represents PsbZ (Ycf9), which is a core low molecular weight transmembrane protein of photosystem II in thylakoid-containing chloroplasts of cyanobacteria and plants. It is thought to be located at the interface of PSII and LHCII (light-harvesting complex II) complexes, the latter containing the light-harvesting antenna. PsbZ appears to act as a structural factor, or linker, that stabilises the PSII-LHCII supercomplexes, which fail to form in PsbZ-deficient mutants. This may in part be due to the marked decrease in two LHCII antenna proteins, CP26 and CP29, found in PsbZ-deficient mutants, which result in structural changes, as well as functional modifications in PSII [PUBMED:11402165]. PsbZ may also be involved in photo-protective processes under sub-optimal growth conditions.
Gene Ontology
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
| Cellular component | photosystem II reaction center (GO:0009539) |
| photosystem II (GO:0009523) | |
| Biological process | photosystem II stabilization (GO:0042549) |
| photosynthesis (GO:0015979) |
Domain organisation
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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Alignments
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 using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...
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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.
| Seed (35) |
Full (1482) |
Representative proteomes | NCBI (419) |
Meta (120) |
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| RP15 (11) |
RP35 (34) |
RP55 (46) |
RP75 (54) |
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| PP/heatmap | 1 | |||||||
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key:
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not generated,
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Format an alignment
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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.
| Seed (35) |
Full (1482) |
Representative proteomes | NCBI (419) |
Meta (120) |
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|---|---|---|---|---|---|---|---|---|
| RP15 (11) |
RP35 (34) |
RP55 (46) |
RP75 (54) |
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| Raw Stockholm | ||||||||
| Gzipped | ||||||||
You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.
External links
MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.
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...
Trees
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
| Seed source: | Pfam-B_2211 (release 4.1) |
| Previous IDs: | YCF9; |
| Type: | Family |
| Author: | Bashton M, Bateman A |
| Number in seed: | 35 |
| Number in full: | 1482 |
| Average length of the domain: | 57.60 aa |
| Average identity of full alignment: | 81 % |
| Average coverage of the sequence by the domain: | 94.87 % |
HMM information
| HMM build commands: |
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
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| Model details: |
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| Model length: | 59 | ||||||||||||
| Family (HMM) version: | 12 | ||||||||||||
| Download: | download the raw HMM for this family |
Species distribution
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Structures
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 Ycf9 domain has been found. There are 17 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 seqence.
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Archea
Eukaryota
Bacteria
Other sequences
Viruses
Unclassified
Viroids
Unclassified sequence