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Q9AI65 (PALH_ERWRD) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 46. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (3) | 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:
Alpha-glucosidase

EC=3.2.1.20
Gene names
Name:palH
OrganismErwinia rhapontici (Pectobacterium rhapontici)
Taxonomic identifier55212 [NCBI]
Taxonomic lineageBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeErwinia

Protein attributes

Sequence length453 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Alpha-glucosidase with broad specificity. Hydrolyzes maltose, palatinose, maltulose, trehalose, trehalulose, turanose, leucrose, sucrose and maltitol. Is not active against alpha-galactosides, e.g. melibiose, and alpha-mannosides. Shows an obligate requirement for an O-alpha-glycosidic linkage, since it is not able to cleave beta-glycosidic bonds (cellobiose, gentiobiose, lactose, sophorose or laminaribiose). Can not hydrolyze phosphorylated alpha-glucosides derivatives. Seems to be involved in the degradation of palatinose, a sucrose isomer that is formed as a reserve material under conditions of excess carbon availability, sequestered in a form unavailable to competitors such as fungi or the host plant, and whose consumption appears to be postponed until the preferentially metabolized carbon source (e.g. sucrose) is depleted. Ref.1

Catalytic activity

Hydrolysis of terminal, non-reducing (1->4)-linked alpha-D-glucose residues with release of alpha-D-glucose. Ref.2

Cofactor

Binds 1 divalent metal ion per subunit. Mn2+ is the most efficient metal, but to a lesser extent, can also use Co2+, Ca2+, Fe2+, Mg2+, Sr2+, and Ni2+. Can not use Zn2+, Cu2+ or Cr2+. Ref.2

Binds 1 NAD+ per subunit. Ref.2

Enzyme regulation

Is inhibited by EDTA in vitro. Ref.2

Pathway

Glycan degradation; palatinose degradation. Ref.1

Subunit structure

Homotetramer. Ref.2

Induction

Down-regulated by sucrose and up-regulated by palatinose. Ref.1 Ref.2

Sequence similarities

Belongs to the glycosyl hydrolase 4 family.

Biophysicochemical properties

Kinetic parameters:

KM=8.58 mM for maltose Ref.2

KM=7.31 mM for maltitol

KM=6.59 mM for trehalose

KM=3.63 mM for trehalulose

KM=22.11 mM for sucrose

KM=10.04 mM for turanose

KM=1.75 mM for maltulose

KM=5.31 mM for leucrose

KM=2.52 mM for palatinose

KM=180 µM for 4-nitrophenyl-alpha-D-glucopyranoside

KM=104 µM for NAD+

KM=47.2 µM for Mn2+

Vmax=1.01 µmol/min/mg enzyme with maltose as substrate

Vmax=0.24 µmol/min/mg enzyme with maltitol as substrate

Vmax=0.51 µmol/min/mg enzyme with trehalose as substrate

Vmax=0.47 µmol/min/mg enzyme with trehalulose as substrate

Vmax=0.31 µmol/min/mg enzyme with sucrose as substrate

Vmax=0.46 µmol/min/mg enzyme with turanose as substrate

Vmax=0.53 µmol/min/mg enzyme with maltulose as substrate

Vmax=0.44 µmol/min/mg enzyme with leucrose as substrate

Vmax=0.70 µmol/min/mg enzyme with palatinose as substrate

Vmax=6.01 µmol/min/mg enzyme with 4-nitrophenyl-alpha-D-glucopyranoside as substrate

Mass spectrometry

Molecular mass is 50216 Da from positions 2 - 453. Determined by ESI. Ref.2

Sequence caution

The sequence AAK28734.1 differs from that shown. Reason: Erroneous initiation.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Initiator methionine11Removed Ref.2
Chain2 – 453452Alpha-glucosidase
PRO_0000389548

Regions

Nucleotide binding3 – 6967NAD By similarity

Sites

Active site1721Proton donor By similarity
Metal binding1711Manganese By similarity
Metal binding2011Manganese By similarity
Binding site1491Substrate By similarity

Experimental info

Mutagenesis1731E → S: Loss of catalytic activity. Ref.2
Mutagenesis1741I → V: No effect on catalytic activity. Ref.2

Sequences

Sequence LengthMass (Da)Tools
Q9AI65 [UniParc].

Last modified November 24, 2009. Version 2.
Checksum: 64B178085AE436AC

FASTA45350,341
        10         20         30         40         50         60 
MATKIVLVGA GSAQFGYGTL GDIFQSRALY GSEIILHDIN PVALAVTEKT AKDFLAKEDL 

        70         80         90        100        110        120 
PFIVSATTDR RTALRGAEFV IISIEVGDRF ALWDLDWQIP QQYGIQQVYG ENGGPGGLFH 

       130        140        150        160        170        180 
SLRIIPPILD ICADVADICP DAWIFNYSNP MSRICTTVHR RFPELNFVGM CHEIASLERY 

       190        200        210        220        230        240 
LPEMLNTSFD NLSLRAGGLN HFSVLLDARY KDSGKDAYAD VRAKAPDYFA SLPGYSDILA 

       250        260        270        280        290        300 
YTRQHGKLVD TEGSTERHAL GGKDSSYPWA DRTLFKEILE KFHCMPITVD SHFGEYISWA 

       310        320        330        340        350        360 
GEVSDHRGIL DFYTFYRNYL GGVQPKIELK LKERVVSIME GILTDSGYEE AAVNIPNRGF 

       370        380        390        400        410        420 
IKQLPEFIAV EVPAIIDRKG VHGIQVDIPP GIGGLLSNQI AIHDLTAEAI IAGSRDLVIQ 

       430        440        450 
ALLVDSVNNQ CRAIPELVDV MISRQQPWLN YLK 

« Hide

References

[1]"Cloning and characterization of the gene cluster for palatinose metabolism from the phytopathogenic bacterium Erwinia rhapontici."
Boernke F., Hajirezaei M., Sonnewald U.
J. Bacteriol. 183:2425-2430(2001) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION IN PALATINOSE METABOLISM, PATHWAY, INDUCTION.
Strain: ATCC 29283 / DSM 4484 / NCPPB 1578 / ICPB ER 102.
[2]"Evolution and biochemistry of family 4 glycosidases: implications for assigning enzyme function in sequence annotations."
Hall B.G., Pikis A., Thompson J.
Mol. Biol. Evol. 26:2487-2497(2009) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE OF 2-26, CATALYTIC ACTIVITY, SUBSTRATE SPECIFICITY, COFACTOR, ENZYME REGULATION, KINETIC PARAMETERS, MASS SPECTROMETRY, SUBUNIT, MUTAGENESIS OF GLU-173 AND ILE-174.
Strain: ATCC 29283 / DSM 4484 / NCPPB 1578 / ICPB ER 102.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF279280 Genomic DNA. Translation: AAK28734.1. Different initiation.

3D structure databases

ProteinModelPortalQ9AI65.
ModBaseSearch...
MobiDBSearch...

Protein family/group databases

CAZyGH4. Glycoside Hydrolase Family 4.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Enzyme and pathway databases

UniPathwayUPA01004.

Family and domain databases

Gene3D3.40.50.720. 1 hit.
3.90.110.10. 1 hit.
InterProIPR001088. Glyco_hydro_4.
IPR022616. Glyco_hydro_4_C.
IPR015955. Lactate_DH/Glyco_Ohase_4_C.
IPR016040. NAD(P)-bd_dom.
[Graphical view]
PfamPF02056. Glyco_hydro_4. 1 hit.
PF11975. Glyco_hydro_4C. 1 hit.
[Graphical view]
PRINTSPR00732. GLHYDRLASE4.
SUPFAMSSF56327. SSF56327. 1 hit.
ProtoNetSearch...

Entry information

Entry namePALH_ERWRD
AccessionPrimary (citable) accession number: Q9AI65
Entry history
Integrated into UniProtKB/Swiss-Prot: November 24, 2009
Last sequence update: November 24, 2009
Last modified: February 19, 2014
This is version 46 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PATHWAY comments

Index of metabolic and biosynthesis pathways

Glycosyl hydrolases

Classification of glycosyl hydrolase families and list of entries