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P23526 (SAHH_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified January 25, 2012. Version 132. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (7) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Adenosylhomocysteinase

Short name=AdoHcyase
EC=3.3.1.1
Alternative name(s):
S-adenosyl-L-homocysteine hydrolase
Gene names
Name:AHCY
Synonyms:SAHH
OrganismHomo sapiens (Human)
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length432 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Adenosylhomocysteine is a competitive inhibitor of S-adenosyl-L-methionine-dependent methyl transferase reactions; therefore adenosylhomocysteinase may play a key role in the control of methylations via regulation of the intracellular concentration of adenosylhomocysteine. Ref.15

Catalytic activity

S-adenosyl-L-homocysteine + H2O = L-homocysteine + adenosine.

Cofactor

Binds 1 NAD per subunit. Ref.14 Ref.15

Pathway

Amino-acid biosynthesis; L-homocysteine biosynthesis; L-homocysteine from S-adenosyl-L-homocysteine: step 1/1.

Subunit structure

Homotetramer. Ref.14

Subcellular location

Cytoplasm. Melanosome. Note: Identified by mass spectrometry in melanosome fractions from stage I to stage IV. Ref.11

Involvement in disease

Defects in AHCY are the cause of hypermethioninemia with S-adenosylhomocysteine hydrolase deficiency (HMAHCHD) [MIM:613752]. A metabolic disorder characterized by hypermethioninemia associated with failure to thrive, mental and motor retardation, facial dysmorphism with abnormal hair and teeth, and myocardiopathy. Ref.17 Ref.18 Ref.19 Ref.20

Sequence similarities

Belongs to the adenosylhomocysteinase family.

Ontologies

Keywords
   Biological processOne-carbon metabolism
   Cellular componentCytoplasm
   Coding sequence diversityPolymorphism
   DiseaseDisease mutation
   LigandNAD
   Molecular functionHydrolase
   PTMAcetylation
   Technical term3D-structure
Complete proteome
Direct protein sequencing
Reference proteome
Gene Ontology (GO)
   Biological processmethylation

Traceable author statement. Source: Reactome

xenobiotic metabolic process

Traceable author statement. Source: Reactome

   Cellular componentcytosol

Traceable author statement. Source: Reactome

melanosome

Inferred from electronic annotation. Source: UniProtKB-SubCell

   Molecular functionadenosylhomocysteinase activity

Traceable author statement Ref.1. Source: UniProtKB

Complete GO annotation...

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Initiator methionine11Removed Ref.7 Ref.8
Chain2 – 432431Adenosylhomocysteinase
PRO_0000116902

Regions

Nucleotide binding157 – 1593NAD
Nucleotide binding222 – 2276NAD
Nucleotide binding299 – 3013NAD

Sites

Binding site571Substrate By similarity
Binding site1311Substrate By similarity
Binding site1561Substrate By similarity
Binding site1861Substrate By similarity
Binding site1901Substrate By similarity
Binding site2431NAD
Binding site2481NAD
Binding site3461NAD
Binding site3531NAD

Amino acid modifications

Modified residue21N-acetylserine Ref.8
Modified residue4081N6-acetyllysine Ref.12

Natural variations

Natural variant381R → W. Ref.16
Corresponds to variant rs13043752 [ dbSNP | Ensembl ].
VAR_052286
Natural variant491R → C in HMAHCHD. Ref.19 Ref.20
VAR_058588
Natural variant861D → G in HMAHCHD. Ref.19 Ref.20
VAR_058589
Natural variant861D → N. Ref.1
VAR_006934
Natural variant891A → V in HMAHCHD. Ref.18
VAR_058590
Natural variant1431Y → C in HMAHCHD. Ref.17 Ref.18
VAR_058591

Secondary structure

................................................................................. 432
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P23526 [UniParc].

Last modified January 23, 2007. Version 4.
Checksum: 2833C025F969553E

FASTA43247,716
        10         20         30         40         50         60 
MSDKLPYKVA DIGLAAWGRK ALDIAENEMP GLMRMRERYS ASKPLKGARI AGCLHMTVET 

        70         80         90        100        110        120 
AVLIETLVTL GAEVQWSSCN IFSTQDHAAA AIAKAGIPVY AWKGETDEEY LWCIEQTLYF 

       130        140        150        160        170        180 
KDGPLNMILD DGGDLTNLIH TKYPQLLPGI RGISEETTTG VHNLYKMMAN GILKVPAINV 

       190        200        210        220        230        240 
NDSVTKSKFD NLYGCRESLI DGIKRATDVM IAGKVAVVAG YGDVGKGCAQ ALRGFGARVI 

       250        260        270        280        290        300 
ITEIDPINAL QAAMEGYEVT TMDEACQEGN IFVTTTGCID IILGRHFEQM KDDAIVCNIG 

       310        320        330        340        350        360 
HFDVEIDVKW LNENAVEKVN IKPQVDRYRL KNGRRIILLA EGRLVNLGCA MGHPSFVMSN 

       370        380        390        400        410        420 
SFTNQVMAQI ELWTHPDKYP VGVHFLPKKL DEAVAEAHLG KLNVKLTKLT EKQAQYLGMS 

       430 
CDGPFKPDHY RY 

« Hide

References

« Hide 'large scale' references
[1]"Sequence of full length cDNA for human S-adenosylhomocysteine hydrolase."
Coulter-Karis D.E., Hershfield M.S.
Ann. Hum. Genet. 53:169-175(1989) [PubMed: 2596825] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], VARIANT ASN-86.
Tissue: Placenta.
[2]"Cloning of human full-length CDSs in BD Creator(TM) system donor vector."
Kalnine N., Chen X., Rolfs A., Halleck A., Hines L., Eisenstein S., Koundinya M., Raphael J., Moreira D., Kelley T., LaBaer J., Lin Y., Phelan M., Farmer A.
Submitted (OCT-2004) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
[3]"Complete sequencing and characterization of 21,243 full-length human cDNAs."
Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. expand/collapse author list , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
Nat. Genet. 36:40-45(2004) [PubMed: 14702039] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Tissue: Umbilical cord blood.
[4]"The DNA sequence and comparative analysis of human chromosome 20."
Deloukas P., Matthews L.H., Ashurst J.L., Burton J., Gilbert J.G.R., Jones M., Stavrides G., Almeida J.P., Babbage A.K., Bagguley C.L., Bailey J., Barlow K.F., Bates K.N., Beard L.M., Beare D.M., Beasley O.P., Bird C.P., Blakey S.E. expand/collapse author list , Bridgeman A.M., Brown A.J., Buck D., Burrill W.D., Butler A.P., Carder C., Carter N.P., Chapman J.C., Clamp M., Clark G., Clark L.N., Clark S.Y., Clee C.M., Clegg S., Cobley V.E., Collier R.E., Connor R.E., Corby N.R., Coulson A., Coville G.J., Deadman R., Dhami P.D., Dunn M., Ellington A.G., Frankland J.A., Fraser A., French L., Garner P., Grafham D.V., Griffiths C., Griffiths M.N.D., Gwilliam R., Hall R.E., Hammond S., Harley J.L., Heath P.D., Ho S., Holden J.L., Howden P.J., Huckle E., Hunt A.R., Hunt S.E., Jekosch K., Johnson C.M., Johnson D., Kay M.P., Kimberley A.M., King A., Knights A., Laird G.K., Lawlor S., Lehvaeslaiho M.H., Leversha M.A., Lloyd C., Lloyd D.M., Lovell J.D., Marsh V.L., Martin S.L., McConnachie L.J., McLay K., McMurray A.A., Milne S.A., Mistry D., Moore M.J.F., Mullikin J.C., Nickerson T., Oliver K., Parker A., Patel R., Pearce T.A.V., Peck A.I., Phillimore B.J.C.T., Prathalingam S.R., Plumb R.W., Ramsay H., Rice C.M., Ross M.T., Scott C.E., Sehra H.K., Shownkeen R., Sims S., Skuce C.D., Smith M.L., Soderlund C., Steward C.A., Sulston J.E., Swann R.M., Sycamore N., Taylor R., Tee L., Thomas D.W., Thorpe A., Tracey A., Tromans A.C., Vaudin M., Wall M., Wallis J.M., Whitehead S.L., Whittaker P., Willey D.L., Williams L., Williams S.A., Wilming L., Wray P.W., Hubbard T., Durbin R.M., Bentley D.R., Beck S., Rogers J.
Nature 414:865-871(2001) [PubMed: 11780052] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[5]Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. expand/collapse author list , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C.
Submitted (SEP-2005) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Tissue: Placenta and Skin.
[7]"Limited proteolysis of S-adenosylhomocysteine hydrolase: implications for the three-dimensional structure."
Gupta R.A., Yuan C.-S., Ault-Riche D.B., Borchardt R.T.
Arch. Biochem. Biophys. 319:365-371(1995) [PubMed: 7786017] [Abstract]
Cited for: PROTEIN SEQUENCE OF 2-6; 104-108 AND 198-202.
[8]Bienvenut W.V., Heiserich L., Gottlieb E.
Submitted (MAR-2008) to UniProtKB
Cited for: PROTEIN SEQUENCE OF 2-34; 95-103; 143-186; 215-226; 336-343 AND 389-405, CLEAVAGE OF INITIATOR METHIONINE, ACETYLATION AT SER-2, MASS SPECTROMETRY.
Tissue: Colon carcinoma.
[9]"Isozyme and DNA analysis of human S-adenosyl-L-homocysteine hydrolase (AHCY)."
Arredondo-Vega F.X., Charlton J.A., Edwards Y.H., Hopkinson D.A., Whitehouse D.B.
Ann. Hum. Genet. 53:157-167(1989) [PubMed: 2574561] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 122-432.
Tissue: Placenta.
[10]"Photoaffinity labeling of human placental S-adenosylhomocysteine hydrolase with [2-3H]8-azido-adenosine."
Yuan C.S., Borchardt R.T.
J. Biol. Chem. 270:16140-16146(1995) [PubMed: 7608178] [Abstract]
Cited for: PROTEIN SEQUENCE OF 175-186 AND 319-327.
[11]"Proteomic and bioinformatic characterization of the biogenesis and function of melanosomes."
Chi A., Valencia J.C., Hu Z.-Z., Watabe H., Yamaguchi H., Mangini N.J., Huang H., Canfield V.A., Cheng K.C., Yang F., Abe R., Yamagishi S., Shabanowitz J., Hearing V.J., Wu C., Appella E., Hunt D.F.
J. Proteome Res. 5:3135-3144(2006) [PubMed: 17081065] [Abstract]
Cited for: SUBCELLULAR LOCATION [LARGE SCALE ANALYSIS], MASS SPECTROMETRY.
Tissue: Melanoma.
[12]"Lysine acetylation targets protein complexes and co-regulates major cellular functions."
Choudhary C., Kumar C., Gnad F., Nielsen M.L., Rehman M., Walther T., Olsen J.V., Mann M.
Science 325:834-840(2009) [PubMed: 19608861] [Abstract]
Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT LYS-408, MASS SPECTROMETRY.
[13]"Initial characterization of the human central proteome."
Burkard T.R., Planyavsky M., Kaupe I., Breitwieser F.P., Buerckstuemmer T., Bennett K.L., Superti-Furga G., Colinge J.
BMC Syst. Biol. 5:17-17(2011) [PubMed: 21269460] [Abstract]
Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
[14]"Structure determination of selenomethionyl S-adenosylhomocysteine hydrolase using data at a single wavelength."
Turner M.A., Yuan C.S., Borchardt R.T., Hershfield M.S., Smith G.D., Howell P.L.
Nat. Struct. Biol. 5:369-376(1998) [PubMed: 9586999] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) IN COMPLEX WITH NAD AND ADENOSINE ANALOG, SUBUNIT, COFACTOR.
Tissue: Placenta.
[15]"Catalytic strategy of S-adenosyl-L-homocysteine hydrolase: transition-state stabilization and the avoidance of abortive reactions."
Yang X., Hu Y., Yin D.H., Turner M.A., Wang M., Borchardt R.T., Howell P.L., Kuczera K., Schowen R.L.
Biochemistry 42:1900-1909(2003) [PubMed: 12590576] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.01 ANGSTROMS) IN COMPLEX WITH NAD AND NEPLANOCIN A, FUNCTION, COFACTOR.
[16]"Effect of genetic variation in the human S-adenosylhomocysteine hydrolase gene on total homocysteine concentrations and risk of recurrent venous thrombosis."
Gellekink H., den Heijer M., Kluijtmans L.A., Blom H.J.
Eur. J. Hum. Genet. 12:942-948(2004) [PubMed: 15241484] [Abstract]
Cited for: VARIANT TRP-38.
[17]"S-adenosylhomocysteine hydrolase deficiency in a human: a genetic disorder of methionine metabolism."
Baric I., Fumic K., Glenn B., Cuk M., Schulze A., Finkelstein J.D., James S.J., Mejaski-Bosnjak V., Pazanin L., Pogribny I.P., Rados M., Sarnavka V., Scukanec-Spoljar M., Allen R.H., Stabler S., Uzelac L., Vugrek O., Wagner C., Zeisel S., Mudd S.H.
Proc. Natl. Acad. Sci. U.S.A. 101:4234-4239(2004) [PubMed: 15024124] [Abstract]
Cited for: VARIANT HMAHCHD CYS-143.
[18]"S-adenosylhomocysteine hydrolase deficiency in a 26-year-old man."
Buist N.R., Glenn B., Vugrek O., Wagner C., Stabler S., Allen R.H., Pogribny I., Schulze A., Zeisel S.H., Baric I., Mudd S.H.
J. Inherit. Metab. Dis. 29:538-545(2006) [PubMed: 16736098] [Abstract]
Cited for: VARIANTS HMAHCHD VAL-89 AND CYS-143.
[19]"S-adenosylhomocysteine hydrolase (AHCY) deficiency: two novel mutations with lethal outcome."
Vugrek O., Beluzic R., Nakic N., Mudd S.H.
Hum. Mutat. 30:E555-E565(2009) [PubMed: 19177456] [Abstract]
Cited for: VARIANTS HMAHCHD CYS-49 AND GLY-86.
[20]"S-adenosylhomocysteine hydrolase deficiency: two siblings with fetal hydrops and fatal outcomes."
Grubbs R., Vugrek O., Deisch J., Wagner C., Stabler S., Allen R., Baric I., Rados M., Mudd S.H.
J. Inherit. Metab. Dis. 33:705-713(2010) [PubMed: 20852937] [Abstract]
Cited for: VARIANTS HMAHCHD CYS-49 AND GLY-86.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
M61831 mRNA. Translation: AAA51681.1.
M61832 mRNA. Translation: AAA51682.1.
BT006697 mRNA. Translation: AAP35343.1.
AK290422 mRNA. Translation: BAF83111.1.
AL356299 Genomic DNA. Translation: CAC09528.1.
CH471077 Genomic DNA. Translation: EAW76279.1.
CH471077 Genomic DNA. Translation: EAW76280.1.
BC010018 mRNA. Translation: AAH10018.1.
BC011606 mRNA. Translation: AAH11606.1.
IPIIPI00012007.
PIRA43629.
RefSeqNP_000678.1. NM_000687.2.
NP_001155238.1. NM_001161766.1.
UniGeneHs.388004.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1A7AX-ray2.80A/B1-432[»]
1LI4X-ray2.01A1-432[»]
3NJ4X-ray2.50A/B/C/D1-432[»]
ProteinModelPortalP23526.
SMRP23526. Positions 3-432.
ModBaseSearch...

Protein-protein interaction databases

IntActP23526. 8 interactions.
MINTMINT-5000523.
STRINGP23526.

PTM databases

PhosphoSiteP23526.

Polymorphism databases

DMDM20141702.

2D gel databases

REPRODUCTION-2DPAGEIPI00012007.

Proteomic databases

PeptideAtlasP23526.
PRIDEP23526.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000217426; ENSP00000217426; ENSG00000101444.
GeneID191.
KEGGhsa:191.
UCSCuc002xai.1. human.

Organism-specific databases

CTD191.
GeneCardsGC20M032868.
H-InvDBHIX0015744.
HGNCHGNC:343. AHCY.
MIM180960. gene.
613752. phenotype.
neXtProtNX_P23526.
Orphanet88618. Psychomotor retardation due to S-adenosylhomocysteine hydrolase deficiency.
GenAtlasSearch...

Phylogenomic databases

eggNOGprNOG13777.
HOGENOMHBG352029.
HOVERGENHBG005041.
InParanoidP23526.
OMAELFTKTE.
OrthoDBEOG4MW862.
PhylomeDBP23526.

Enzyme and pathway databases

ReactomeREACT_111217. Metabolism.

Gene expression databases

ArrayExpressP23526.
BgeeP23526.
CleanExHS_AHCY.
GenevestigatorP23526.
GermOnlineENSG00000101444. Homo sapiens.

Family and domain databases

InterProIPR000043. Adenosylhomocysteinase.
IPR015878. Ado_hCys_hydrolase_NAD-bd.
IPR020082. S-Ado-L-homoCys_hydrolase_CS.
[Graphical view]
KOK01251.
PANTHERPTHR23420. Ad_hcy_hydrolase. 1 hit.
PfamPF05221. AdoHcyase. 1 hit.
PF00670. AdoHcyase_NAD. 1 hit.
[Graphical view]
PIRSFPIRSF001109. Ad_hcy_hydrolase. 1 hit.
SMARTSM00996. AdoHcyase. 1 hit.
SM00997. AdoHcyase_NAD. 1 hit.
[Graphical view]
TIGRFAMsTIGR00936. AhcY. 1 hit.
PROSITEPS00738. ADOHCYASE_1. 1 hit.
PS00739. ADOHCYASE_2. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

NextBio780.
SOURCESearch...

Entry information

Entry nameSAHH_HUMAN
AccessionPrimary (citable) accession number: P23526
Secondary accession number(s): A8K307, E1P5P2, Q96A36
Entry history
Integrated into UniProtKB/Swiss-Prot: November 1, 1991
Last sequence update: January 23, 2007
Last modified: January 25, 2012
This is version 132 of the entry and version 4 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

Human chromosome 20

Human chromosome 20: entries, gene names and cross-references to MIM

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

PATHWAY comments

Index of metabolic and biosynthesis pathways

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

SIMILARITY comments

Index of protein domains and families