<p>Provides any useful information about the protein, mostly biological knowledge.</p><p><a href='../manual/function_section' target='_top'>More...</a></p>Functionⁱ

<p>Describes the catalytic activity of an enzyme, i.e. the chemical reaction it catalyzes. This information usually correlates with the presence of an EC (Enzyme Commission) number in the ‘Names and taxonomy’ section.</p><p><a href='../manual/catalytic_activity' target='_top'>More...</a></p>Catalytic activityⁱ

<p>Describes the metabolic pathway(s) associated with a protein.</p><p><a href='../manual/pathway' target='_top'>More...</a></p>Pathwayⁱ

Sites

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Is used for enzymes and indicates the residues directly involved in catalysis.</p><p><a href='../manual/act_site' target='_top'>More...</a></p>Active sitei	49 – 49	1	Proton acceptor
<p>Is used for enzymes and indicates the residues directly involved in catalysis.</p><p><a href='../manual/act_site' target='_top'>More...</a></p>Active sitei	60 – 60	1	Proton acceptor

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:</p><p><a href='../manual/gene_ontology' target='_top'>More...</a></p>GO - Molecular functionⁱ

1. tryptophan synthase activity Source: UniProtKB-HAMAP

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Molecular functionⁱ

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Biological processⁱ

Enzyme and pathway databases

<p>Provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.</p><p><a href='../manual/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyⁱ

<p>Describes post-translational modifications (PTMs) and/or processing events.</p><p><a href='../manual/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingⁱ

Molecule processing

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Describes the extent of a polypeptide chain in the mature protein following processing.</p><p><a href='../manual/chain' target='_top'>More...</a></p>Chaini	1 – 268	268	Tryptophan synthase alpha chain		PRO_0000098839	Add BLAST

Proteomic databases

<p>Provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.</p><p><a href='../manual/interaction_section' target='_top'>More...</a></p>Interactionⁱ

<p>Provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the ‘Function’ section).</p><p><a href='../manual/subunit_structure' target='_top'>More...</a></p>Subunit structureⁱ

<p>Provides information about binary protein-protein interactions. The data presented in this section are a quality-filtered subset of binary interactions automatically derived from the <a href="http://www.ebi.ac.uk/intact/">IntAct database</a>. It is updated on a monthly basis. Each binary interaction is displayed on a separate line.</p><p><a href='../manual/binary_interactions' target='_top'>More...</a></p>Binary interactionsⁱ

Protein-protein interaction databases

<p>Provides information on the tertiary structure of a protein.</p><p><a href='../manual/structure_section' target='_top'>More...</a></p>Structureⁱ

Secondary structure

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	3 – 13	11	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	18 – 24	7	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined hydrogen-bonded turns within the protein sequence. These elements correspond to the <span class="caps">DSSP</span> secondary structure code ‘T’.</p><p><a href='../manual/turn' target='_top'>More...</a></p>Turni	25 – 28	4	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1TTP
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	30 – 42	13	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	46 – 51	6	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	58 – 60	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:2J9Z
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	62 – 73	12	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	78 – 91	14	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	93 – 95	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	97 – 101	5	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	103 – 107	5	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	111 – 121	11	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	125 – 128	4	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	133 – 135	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	137 – 145	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	149 – 151	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1QOP
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	160 – 169	10	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	174 – 181	8	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	185 – 187	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1QOP
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	194 – 202	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	208 – 213	6	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	217 – 225	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	229 – 233	5	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	235 – 243	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined hydrogen-bonded turns within the protein sequence. These elements correspond to the <span class="caps">DSSP</span> secondary structure code ‘T’.</p><p><a href='../manual/turn' target='_top'>More...</a></p>Turni	244 – 246	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	248 – 264	17	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:4HT3
<p>Is used to indicate the positions of experimentally determined hydrogen-bonded turns within the protein sequence. These elements correspond to the <span class="caps">DSSP</span> secondary structure code ‘T’.</p><p><a href='../manual/turn' target='_top'>More...</a></p>Turni	265 – 267	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1K8Z

3D structure databases

Miscellaneous databases

<p>Provides information on sequence similarities with other proteins and the domain(s) present in a protein.</p><p><a href='../manual/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsⁱ

<p>Provides information about the sequence similarity with other proteins.</p><p><a href='../manual/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesⁱ

Phylogenomic databases

Family and domain databases

<p>Displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including length and molecular weight.</p><p><a href='../manual/sequences_section' target='_top'>More...</a></p>Sequenceⁱ

<p>Indicates if the canonical sequence displayed by default in the entry is complete or not.</p><p><a href='../manual/sequence_status' target='_top'>More...</a></p>Sequence statusⁱ: Complete.

        10         20         30         40         50
MERYENLFAQ LNDRREGAFV PFVTLGDPGI EQSLKIIDTL IDAGADALEL 
        60         70         80         90        100
GVPFSDPLAD GPTIQNANLR AFAAGVTPAQ CFEMLALIRE KHPTIPIGLL 
       110        120        130        140        150
MYANLVFNNG IDAFYARCEQ VGVDSVLVAD VPVEESAPFR QAALRHNIAP 
       160        170        180        190        200
IFICPPNADD DLLRQVASYG RGYTYLLSRS GVTGAENRGA LPLHHLIEKL 
       210        220        230        240        250
KEYHAAPALQ GFGISSPEQV SAAVRAGAAG AISGSAIVKI IEKNLASPKQ 
       260 
MLAELRSFVS AMKAASRA                                  

Sequence databases

Genome annotation databases

<p>Is used to point to information related to entries and found in data collections other than UniProtKB.</p><p><a href='../manual/cross_references_section' target='_top'>More...</a></p>Cross-referencesⁱ

Sequence databases

3D structure databases

Protein-protein interaction databases

Proteomic databases

Protocols and materials databases

Genome annotation databases

Phylogenomic databases

Enzyme and pathway databases

Miscellaneous databases

Family and domain databases

<p>Contains the literature citations that are the sources of data used to annotate the entry. Each reference is numbered and contains several subsections allowing a precise description of a given citation.</p><p><a href='../manual/publications_section' target='_top'>More...</a></p>Publicationsⁱ

1. "Nucleotide sequences of trpA of Salmonella typhimurium and Escherichia coli: an evolutionary comparison."
   Nichols B.P., Yanofsky C.
   Proc. Natl. Acad. Sci. U.S.A. 76:5244-5248(1979) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
2. "Procedure for production of hybrid genes and proteins and its use in assessing significance of amino acid differences in homologous tryptophan synthetase alpha polypeptides."
   Schneider W.P., Nichols B.P., Yanofsky C.
   Proc. Natl. Acad. Sci. U.S.A. 78:2169-2173(1981) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
3. "Complete genome sequence of Salmonella enterica serovar Typhimurium LT2."
   McClelland M., Sanderson K.E., Spieth J., Clifton S.W., Latreille P., Courtney L., Porwollik S., Ali J., Dante M., Du F., Hou S., Layman D., Leonard S., Nguyen C., Scott K., Holmes A., Grewal N., Mulvaney E.

   , Ryan E., Sun H., Florea L., Miller W., Stoneking T., Nhan M., Waterston R., Wilson R.K.
   Nature 413:852-856(2001) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
   Strain: LT2 / SGSC1412 / ATCC 700720.
   
4. "Amino acid sequence studies with the tryptophan synthetase alpha chain of Salmonella typhimurium."
   Li S.-L., Yanofsky C.
   J. Biol. Chem. 248:1830-1836(1973) [PubMed] [Europe PMC] [Abstract]
   Cited for: PARTIAL PROTEIN SEQUENCE.
5. "Three-dimensional structure of the tryptophan synthase alpha 2 beta 2 multienzyme complex from Salmonella typhimurium."
   Hyde C.C., Ahmed S.A., Padlan E.A., Miles E.W., Davies D.R.
   J. Biol. Chem. 263:17857-17871(1988) [PubMed] [Europe PMC] [Abstract]
   Cited for: X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS).
6. "Crystal structures of a mutant (betaK87T) tryptophan synthase alpha2beta2 complex with ligands bound to the active sites of the alpha- and beta-subunits reveal ligand-induced conformational changes."
   Rhee S., Parris K.D., Hyde C.C., Ahmed S.A., Miles E.W., Davies D.R.
   Biochemistry 36:7664-7680(1997) [PubMed] [Europe PMC] [Abstract]
   Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS).
7. "Cryo-crystallography of a true substrate, indole-3-glycerol phosphate, bound to a mutant (alphaD60N) tryptophan synthase alpha2beta2 complex reveals the correct orientation of active site alphaGlu49."
   Rhee S., Miles E.W., Davies D.R.
   J. Biol. Chem. 273:8553-8555(1998) [PubMed] [Europe PMC] [Abstract]
   Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS).
8. "Refined structure of the native form of the tryptophan synthase multienzyme complex from Salmonella typhimurium."
   Hyde C.C., Parris K.D., Bhat T.N., Brown C., Ahmed S.A., Miles E.W., Davies D.R.
   Submitted (JUL-1998) to the PDB data bank
   Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
9. "Crystallographic studies of phosphonate-based alpha-reaction transition-state analogues complexed to tryptophan synthase."
   Sachpatzidis A., Dealwis C., Lubetsky J.B., Liang P.-H., Anderson K.S., Lolis E.
   Biochemistry 38:12665-12674(1999) [PubMed] [Europe PMC] [Abstract]
   Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
10. "Structural basis for the impaired channeling and allosteric inter-subunit communication in the beta A169L/beta C170W mutant of tryptophan synthase."
    Weyand M., Schlichting I.
    J. Biol. Chem. 275:41058-41063(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.25 ANGSTROMS).
11. "On the role of alphaThr183 in the allosteric regulation and catalytic mechanism of tryptophan synthase."
    Kulik V., Weyand M., Seidel R., Niks D., Arac D., Dunn M.F., Schlichting I.
    J. Mol. Biol. 324:677-690(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (1.75 ANGSTROMS) OF 17-268.

<p>Provides general information on the entry.</p><p><a href='../manual/entry_information_section' target='_top'>More...</a></p>Entry informationⁱ

<p>Contains any relevant information that doesn’t fit in any other defined sections</p><p><a href='../manual/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousⁱ

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Technical termⁱ

Documents

1. PATHWAY comments
   Index of metabolic and biosynthesis pathways
2. PDB cross-references
   Index of Protein Data Bank (PDB) cross-references
3. SIMILARITY comments
   Index of protein domains and families

External Data

<p>Provides links to the UniProt Reference Clusters (<a href="/help/uniref">UniRef</a>). UniRef consists of clusters for UniProtKB sequences (including isoforms) and selected UniParc sequences, in order to obtain complete coverage of the sequence space at resolutions of 100%, 90% and 50% identity.</p><p><a href='../manual/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsⁱ