ID   AMNB_COMTE              Reviewed;         312 AA.
AC   Q6J1Z6; Q38M41;
DT   26-JUN-2013, integrated into UniProtKB/Swiss-Prot.
DT   26-JUN-2013, sequence version 2.
DT   13-SEP-2023, entry version 61.
DE   RecName: Full=2-aminophenol 1,6-dioxygenase subunit beta {ECO:0000303|PubMed:15580337};
DE            EC=1.13.11.74;
DE   AltName: Full=2-amino-5-chlorophenol 1,6-dioxygenase subunit beta {ECO:0000312|EMBL:ABB13577.1};
DE            EC=1.13.11.76;
GN   Name=cnbCb {ECO:0000312|EMBL:ABB13577.1};
GN   Synonyms=amnB {ECO:0000312|EMBL:AAT35226.1};
OS   Comamonas testosteroni (Pseudomonas testosteroni).
OG   Plasmid pCNB1.
OC   Bacteria; Pseudomonadota; Betaproteobacteria; Burkholderiales;
OC   Comamonadaceae; Comamonas.
OX   NCBI_TaxID=285;
RN   [1] {ECO:0000305, ECO:0000312|EMBL:AAT35226.1}
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 1-8, FUNCTION,
RP   CATALYTIC ACTIVITY, COFACTOR, SUBSTRATE SPECIFICITY, ACTIVITY REGULATION,
RP   BIOPHYSICOCHEMICAL PROPERTIES, AND SUBUNIT.
RC   STRAIN=CNB-1 {ECO:0000269|PubMed:15580337}; PLASMID=pCNB1;
RX   PubMed=15580337; DOI=10.1007/s00203-004-0738-5;
RA   Wu J.F., Sun C.W., Jiang C.Y., Liu Z.P., Liu S.J.;
RT   "A novel 2-aminophenol 1,6-dioxygenase involved in the degradation of p-
RT   chloronitrobenzene by Comamonas strain CNB-1: purification, properties,
RT   genetic cloning and expression in Escherichia coli.";
RL   Arch. Microbiol. 183:1-8(2005).
RN   [2] {ECO:0000305, ECO:0000312|EMBL:ABB13577.1}
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, AND PATHWAY.
RC   STRAIN=CNB-1 {ECO:0000269|PubMed:16517619}; PLASMID=pCNB1;
RX   PubMed=16517619; DOI=10.1128/aem.72.3.1759-1765.2006;
RA   Wu J.F., Jiang C.Y., Wang B.J., Ma Y.F., Liu Z.P., Liu S.J.;
RT   "Novel partial reductive pathway for 4-chloronitrobenzene and nitrobenzene
RT   degradation in Comamonas sp. strain CNB-1.";
RL   Appl. Environ. Microbiol. 72:1759-1765(2006).
RN   [3] {ECO:0000305, ECO:0000312|EMBL:ABB13577.1}
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], AND PATHWAY.
RC   STRAIN=CNB-1 {ECO:0000269|PubMed:17526790}; PLASMID=pCNB1;
RX   PubMed=17526790; DOI=10.1128/aem.00616-07;
RA   Ma Y.F., Wu J.F., Wang S.Y., Jiang C.Y., Zhang Y., Qi S.W., Liu L.,
RA   Zhao G.P., Liu S.J.;
RT   "Nucleotide sequence of plasmid pCNB1 from Comamonas strain CNB-1 reveals
RT   novel genetic organization and evolution for 4-chloronitrobenzene
RT   degradation.";
RL   Appl. Environ. Microbiol. 73:4477-4483(2007).
RN   [4] {ECO:0000305, ECO:0000312|PDB:3VSG}
RP   X-RAY CRYSTALLOGRAPHY (2.30 ANGSTROMS) IN COMPLEX WITH ALPHA SUBUNIT AND IN
RP   COMPLEXES WITH REACTION INTERMEDIATE; PRODUCT; INHIBITOR AND IRON,
RP   COFACTOR, ACTIVITY REGULATION, BIOPHYSICOCHEMICAL PROPERTIES, SUBUNIT,
RP   REACTION MECHANISM, AND MUTAGENESIS OF HIS-13; HIS-62; TYR-129; HIS-195 AND
RP   GLU-251.
RC   STRAIN=CNB-1 {ECO:0000269|PubMed:23275161}; PLASMID=pCNB1;
RX   PubMed=23275161; DOI=10.1107/s0907444912042072;
RA   Li de F., Zhang J.Y., Hou Y.J., Liu L., Hu Y., Liu S.J., Wang da C.,
RA   Liu W.;
RT   "Structures of aminophenol dioxygenase in complex with intermediate,
RT   product and inhibitor.";
RL   Acta Crystallogr. D 69:32-43(2013).
CC   -!- FUNCTION: Component of the 2-aminophenol 1,6-dioxygenase (APD) complex
CC       that catalyzes the ring fission of 2-aminophenol to produce 2-
CC       aminomuconic semialdehyde. CnbCb seems to be the catalytic subunit of
CC       the complex. Also active on other substrates such as 2-amino-5-
CC       chlorophenol (68% activity), protocatechuate (33% activity) and
CC       catechol (5% activity). Both 2-aminophenol and 2-amino-5-cholorophenol
CC       are likely native substrates for this dioxygenase which is involved in
CC       the reductive degradation pathway of both nitrobenzene (NB) and 4-
CC       chloronitrobenzene (4-CNB), allowing C.testosteroni strain CNB-1 to
CC       grow on these compounds as sole source of carbon, nitrogen, and energy.
CC       {ECO:0000269|PubMed:15580337, ECO:0000269|PubMed:16517619}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=2-aminophenol + O2 = 2-aminomuconate 6-semialdehyde;
CC         Xref=Rhea:RHEA:26305, ChEBI:CHEBI:15379, ChEBI:CHEBI:18112,
CC         ChEBI:CHEBI:77634; EC=1.13.11.74;
CC         Evidence={ECO:0000269|PubMed:15580337};
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=2-amino-5-chlorophenol + O2 = 2-amino-5-chloromuconate 6-
CC         semialdehyde; Xref=Rhea:RHEA:37543, ChEBI:CHEBI:15379,
CC         ChEBI:CHEBI:75051, ChEBI:CHEBI:75057; EC=1.13.11.76;
CC         Evidence={ECO:0000269|PubMed:15580337};
CC   -!- COFACTOR:
CC       Name=Fe(2+); Xref=ChEBI:CHEBI:29033;
CC         Evidence={ECO:0000269|PubMed:15580337, ECO:0000269|PubMed:23275161};
CC       Note=Binds 2 Fe(2+) ions per APD complex. The iron ions are bound to
CC       the beta subunit. {ECO:0000269|PubMed:15580337,
CC       ECO:0000269|PubMed:23275161};
CC   -!- ACTIVITY REGULATION: Complete loss of activity in the presence of
CC       Ni(2+), Co(2+), Cd(2+), Zn(2+) and hydrogen peroxide, however activity
CC       with hydrogen peroxide partially restored upon addition of excess
CC       ascorbate. Partially inhibited by Fe(2+), Mg(2+), Ca(2+), Mn(2+),
CC       Cu(2+) and also by EDTA, at 2 mM concentration. Total activity
CC       inhibited in the presence of catechol or 4-nitrocatechol but completely
CC       restored after removal of catechol and addition of 2 mM Fe(2+) and 5 mM
CC       ascorbate. {ECO:0000269|PubMed:15580337, ECO:0000269|PubMed:23275161}.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Kinetic parameters:
CC         KM=0.89 uM for 2-aminophenol {ECO:0000269|PubMed:15580337};
CC         KM=17.1 uM for 2-aminophenol {ECO:0000269|PubMed:23275161};
CC         KM=0.77 uM for 2-amino-5-chlorophenol {ECO:0000269|PubMed:15580337};
CC         KM=6.84 uM for catechol {ECO:0000269|PubMed:23275161};
CC         KM=77.5 uM for oxygen (in the presence of 2-aminophenol)
CC         {ECO:0000269|PubMed:23275161};
CC         KM=58.3 uM for oxygen (in the presence of catechol)
CC         {ECO:0000269|PubMed:23275161};
CC         Vmax=44.6 umol/min/mg enzyme with 2-aminophenol as substrate
CC         {ECO:0000269|PubMed:15580337};
CC         Vmax=19 umol/min/mg enzyme with 2-aminophenol as substrate
CC         {ECO:0000269|PubMed:23275161};
CC         Vmax=19.3 umol/min/mg enzyme with 2-amino-5-chlorophenol as substrate
CC         {ECO:0000269|PubMed:15580337};
CC         Vmax=1.12 umol/min/mg enzyme with catechol as substrate
CC         {ECO:0000269|PubMed:23275161};
CC   -!- PATHWAY: Xenobiotic degradation; nitrobenzene degradation.
CC       {ECO:0000269|PubMed:16517619, ECO:0000269|PubMed:17526790}.
CC   -!- PATHWAY: Xenobiotic degradation; 4-chloronitrobenzene degradation.
CC   -!- SUBUNIT: The APD complex is a heterotetramer of 2 alpha (CnbCa) and 2
CC       beta (CnbCb) subunits. {ECO:0000269|PubMed:15580337,
CC       ECO:0000269|PubMed:23275161}.
CC   -!- MISCELLANEOUS: Not active on 4-methylcatechol, 4-chlorocatechol, 2,4-
CC       dihydroxybenzoate, o-nitrophenol, p-nitrophenol or 4-nitrocatechol.
CC   -!- SIMILARITY: Belongs to the LigB/MhpB extradiol dioxygenase family.
CC       {ECO:0000255}.
CC   -!- SEQUENCE CAUTION:
CC       Sequence=AAT35226.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305};
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; AY605054; AAT35226.1; ALT_INIT; Genomic_DNA.
DR   EMBL; EF079106; ABB13577.1; -; Genomic_DNA.
DR   RefSeq; YP_001967698.1; NC_010935.1.
DR   PDB; 3VSG; X-ray; 2.40 A; B/D=1-312.
DR   PDB; 3VSH; X-ray; 2.70 A; B/D=1-312.
DR   PDB; 3VSI; X-ray; 2.50 A; B/D=1-312.
DR   PDB; 3VSJ; X-ray; 2.30 A; B/D=1-312.
DR   PDBsum; 3VSG; -.
DR   PDBsum; 3VSH; -.
DR   PDBsum; 3VSI; -.
DR   PDBsum; 3VSJ; -.
DR   AlphaFoldDB; Q6J1Z6; -.
DR   SMR; Q6J1Z6; -.
DR   KEGG; ag:AAT35226; -.
DR   PATRIC; fig|688245.4.peg.54; -.
DR   BioCyc; MetaCyc:MONOMER-13344; -.
DR   BRENDA; 1.13.11.74; 1590.
DR   UniPathway; UPA00923; -.
DR   UniPathway; UPA01033; -.
DR   GO; GO:0051213; F:dioxygenase activity; IEA:UniProtKB-KW.
DR   GO; GO:0008198; F:ferrous iron binding; IEA:InterPro.
DR   GO; GO:0019439; P:aromatic compound catabolic process; IEA:UniProtKB-KW.
DR   CDD; cd07372; 2A5CPDO_B; 1.
DR   Gene3D; 3.40.830.10; LigB-like; 1.
DR   InterPro; IPR034943; 2A5CPDO_B.
DR   InterPro; IPR004183; Xdiol_dOase_suB.
DR   Pfam; PF02900; LigB; 1.
DR   SUPFAM; SSF53213; LigB-like; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Aromatic hydrocarbons catabolism; Dioxygenase;
KW   Direct protein sequencing; Iron; Metal-binding; Oxidoreductase; Plasmid.
FT   CHAIN           1..312
FT                   /note="2-aminophenol 1,6-dioxygenase subunit beta"
FT                   /id="PRO_0000422781"
FT   BINDING         13
FT                   /ligand="Fe cation"
FT                   /ligand_id="ChEBI:CHEBI:24875"
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   BINDING         62
FT                   /ligand="Fe cation"
FT                   /ligand_id="ChEBI:CHEBI:24875"
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   BINDING         251
FT                   /ligand="Fe cation"
FT                   /ligand_id="ChEBI:CHEBI:24875"
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   MUTAGEN         13
FT                   /note="H->A: Loss of enzyme activity."
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   MUTAGEN         62
FT                   /note="H->A: Loss of enzyme activity."
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   MUTAGEN         129
FT                   /note="Y->F: Loss of enzyme activity."
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   MUTAGEN         195
FT                   /note="H->Q: Loss of enzyme activity."
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   MUTAGEN         251
FT                   /note="E->A: Loss of enzyme activity."
FT                   /evidence="ECO:0000269|PubMed:23275161"
FT   CONFLICT        8
FT                   /note="G -> E (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000269|PubMed:15580337"
FT   STRAND          2..10
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           16..19
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           35..51
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          54..72
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          75..82
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   TURN            87..89
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          91..98
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           100..112
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          117..120
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           129..138
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          146..153
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           154..157
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           160..181
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          184..189
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           208..210
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           216..231
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           234..248
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           251..254
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           256..263
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          272..279
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          282..290
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   HELIX           291..294
FT                   /evidence="ECO:0007829|PDB:3VSJ"
FT   STRAND          298..301
FT                   /evidence="ECO:0007829|PDB:3VSJ"
SQ   SEQUENCE   312 AA;  35040 MW;  E05323C35EB8EFA4 CRC64;
     MQGEIIAGFL APHPPHLVYG ENPPQNEPRS QGGWEVLRWA YERARERLDA MKPDVLLVHS
     PHWITSVGHH FLGVPELSGK SVDPIFPNVF RYDFSLNVDV ELAEACAEEG RKAGLVTKMM
     RNPKFRVDYG TITTLHLIRP QWDIPVVGIS ANNSPYYLNT KEGMSEMDVL GKATREAIRK
     TGRKAVLLAS NTLSHWHFHE EPTIPEDMSK EYPATMAGYQ WDIRMIELMR QGKTSEVFKL
     LPQFIDEAFA EVKSGAFTWM HAAMQYPELA AELFGYGTVI GTGNAVMEWD LRKAGLSMLG
     AADQKQRSAA VA
//