IABF_BIFLN
ID IABF_BIFLN Reviewed; 566 AA.
AC Q841V6;
DT 01-MAY-2013, integrated into UniProtKB/Swiss-Prot.
DT 01-JUN-2003, sequence version 1.
DT 03-AUG-2022, entry version 65.
DE RecName: Full=Intracellular exo-alpha-(1->5)-L-arabinofuranosidase;
DE Short=ABF;
DE EC=3.2.1.55;
DE AltName: Full=Intracellular arabinan exo-alpha-(1->5)-L-arabinosidase;
DE Short=Arabinosidase;
GN Name=abfB;
OS Bifidobacterium longum.
OC Bacteria; Actinobacteria; Bifidobacteriales; Bifidobacteriaceae;
OC Bifidobacterium.
OX NCBI_TaxID=216816;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, CATALYTIC ACTIVITY,
RP SUBCELLULAR LOCATION, ACTIVITY REGULATION, BIOPHYSICOCHEMICAL PROPERTIES,
RP SUBSTRATE SPECIFICITY, AND SUBUNIT.
RC STRAIN=B667;
RX PubMed=12957891; DOI=10.1128/aem.69.9.5096-5103.2003;
RA Margolles A., de los Reyes-Gavilan C.G.;
RT "Purification and functional characterization of a novel alpha-L-
RT arabinofuranosidase from Bifidobacterium longum B667.";
RL Appl. Environ. Microbiol. 69:5096-5103(2003).
CC -!- FUNCTION: Involved in the degradation of arabinan and is a key enzyme
CC in the complete degradation of the plant cell wall. Catalyzes the
CC cleavage of terminal alpha-(1->5)-arabinofuranosyl bonds in different
CC hemicellulosic homopolysaccharides (branched and debranched arabinans).
CC It is active with sugar beet arabinan and wheat arabinoxylan. It also
CC exhibited activity against alpha-(1->5)-linked arabinobiose,
CC arabinotriose, arabinotetraose, and arabinopentaose.
CC {ECO:0000269|PubMed:12957891}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=Hydrolysis of terminal non-reducing alpha-L-arabinofuranoside
CC residues in alpha-L-arabinosides.; EC=3.2.1.55;
CC Evidence={ECO:0000269|PubMed:12957891};
CC -!- ACTIVITY REGULATION: Completely inhibited by Hg(2+) and Cu(2+) ions,
CC whereas 1 mM Zn(2+) inhibited activity by 51%.
CC {ECO:0000269|PubMed:12957891}.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=0.295 mM for p-nitrophenyl alpha-L-arabinofuranoside (pNP-Araf)(at
CC pH 6 and 45 degrees Celsius) {ECO:0000269|PubMed:12957891};
CC Vmax=0.83 umol/min/mg enzyme with arabinan as substrate (at pH 6 and
CC 45 degrees Celsius) {ECO:0000269|PubMed:12957891};
CC Vmax=1.22 umol/min/mg enzyme with arabinoxylan as substrate (at pH 6
CC and 45 degrees Celsius) {ECO:0000269|PubMed:12957891};
CC pH dependence:
CC Optimum pH is 6. The enzyme retains full activity at pH values from
CC 5.5 to 7.5. After exposure to pH 4.5, the activity is reduced by 40%,
CC and no residual activity is detected at pH values below 4.5 or above
CC 7.5. {ECO:0000269|PubMed:12957891};
CC Temperature dependence:
CC Optimum temperature is 45 degrees Celsius. The enzymatic activity
CC decreases significantly at temperatures below 35 degrees Celsius and
CC above 60 degrees Celsius, although considerable levels of activity
CC are still detected at 20 and 70 degrees Celsius.
CC {ECO:0000269|PubMed:12957891};
CC -!- PATHWAY: Glycan metabolism; L-arabinan degradation.
CC -!- SUBUNIT: Homohexamer; trimer of dimers. {ECO:0000305|PubMed:12957891}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000305|PubMed:12957891}.
CC -!- SIMILARITY: Belongs to the glycosyl hydrolase 51 family. {ECO:0000305}.
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DR EMBL; AY259087; AAO84266.1; -; Genomic_DNA.
DR RefSeq; WP_013410312.1; NZ_QSPR01000001.1.
DR AlphaFoldDB; Q841V6; -.
DR SMR; Q841V6; -.
DR CAZy; GH51; Glycoside Hydrolase Family 51.
DR eggNOG; COG3534; Bacteria.
DR OMA; DRDFTIG; -.
DR BRENDA; 3.2.1.55; 851.
DR SABIO-RK; Q841V6; -.
DR UniPathway; UPA00667; -.
DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR GO; GO:0046556; F:alpha-L-arabinofuranosidase activity; IEA:UniProtKB-EC.
DR GO; GO:0031222; P:arabinan catabolic process; IEA:UniProtKB-UniPathway.
DR GO; GO:0046373; P:L-arabinose metabolic process; IEA:InterPro.
DR Gene3D; 2.60.40.1180; -; 1.
DR InterPro; IPR010720; Alpha-L-AF_C.
DR InterPro; IPR013780; Glyco_hydro_b.
DR InterPro; IPR017853; Glycoside_hydrolase_SF.
DR Pfam; PF06964; Alpha-L-AF_C; 1.
DR SMART; SM00813; Alpha-L-AF_C; 1.
DR SUPFAM; SSF51445; SSF51445; 1.
PE 1: Evidence at protein level;
KW Carbohydrate metabolism; Cytoplasm; Glycosidase; Hydrolase.
FT CHAIN 1..566
FT /note="Intracellular exo-alpha-(1->5)-L-
FT arabinofuranosidase"
FT /id="PRO_0000422127"
FT REGION 1..39
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT ACT_SITE 215
FT /note="Proton donor/acceptor"
FT /evidence="ECO:0000250"
FT ACT_SITE 340
FT /note="Nucleophile"
FT /evidence="ECO:0000250"
FT BINDING 69
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 114
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 214..215
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 286
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 340
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 409
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT SITE 344
FT /note="Important for substrate recognition"
FT /evidence="ECO:0000250"
FT SITE 409
FT /note="Important for substrate recognition"
FT /evidence="ECO:0000250"
SQ SEQUENCE 566 AA; 61548 MW; ACF964B9B6C0DFBC CRC64;
MTTHNSQYSA ETTHPDKQES SPAPTAAGTT ASNVSTTGNA TTPDASIALN ADATPVADVP
PRLFGSFVEH LGRCVYGGIY EPSHPTADEN GFRQDVLDLV KELGVTCVRY PGGNFVSNYN
WEDGIGPREN RPMRRDLAWH CTETNEMGID DFYRWSQKAG TEIMLAVNMG TRGLKAALDE
LEYVNGAPGT AWADQRVANG IEEPMDIKMW CIGNEMDGPW QVGHMSPEEY AGAVDKVAHA
MKLAESGLEL VACGSSGAYM PTFGTWEKTV LTKAYENLDF VSCHAYYFDR GHKTRAAASM
QDFLASSEDM TKFIATVSDA ADQAREANNG TKDIALSFDE WGVWYSDKWN EQEDQWKAEA
AQGLHHEPWP KSPHLLEDIY TAADAVVEGS LMITLLKHCD RVRSASRAQL VNVIAPIMAE
EHGPAWRQTT FYPFAEAALH ARGQAYAPAI SSPTIHTEAY GDVPAIDAVV TWDEQARTGL
LLAVNRDANT PHTLTIDLSG LPGLPGLGTL ALGKAQLLHE DDPYRTNTAE APEAVTPQPL
DIAMNATGTC TATLPAISWI SVEFHG
