B3EWR5 (HEXL_LUPAL) Reviewed, UniProtKB/Swiss-Prot
Last modified February 19, 2014. Version 5. History...
Names and origin
|Protein names||Recommended name:|
|Organism||Lupinus albus (White lupin) (Lupinus termis)|
|Taxonomic identifier||3870 [NCBI]|
|Taxonomic lineage||Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › Gunneridae › Pentapetalae › rosids › fabids › Fabales › Fabaceae › Papilionoideae › Genisteae › Lupinus|
|Sequence length||26 AA.|
|Protein existence||Evidence at protein level|
General annotation (Comments)
Has hexosaminidase activity. Active with both p-nitrophenyl-beta-D-N-acetylglucosamine (pNP-GlcNAc) and p-nitrophenyl-beta-D-N-acetylgalactosamine (pNP-GalNAc). Not active toward p-nitrophenyl-beta-D-N,N'-diacetylchitobiose (pNP-(GlcNAc)2) or p-nitrophenyl-beta-D-N,N',N''-triacetylchitobiose (pNP-(GlcNAc)3). Removes terminal GlcNAc and may be involved in storage protein degradation. Ref.1 Ref.1
Inhibited by AgNO3 at a concentration of 0.1 mM. Strongly inhibited by CdCl2, ZnCl2 and FeCl3 and moderately by CoCl2, CuSO4 and NiCl2 at 10 mM concentration. CaCl2, MgCl2, MnSO4 and KI also have a slight inhibitory effect of 20%-25% at 10 mM concentration. Activated to a small extent by MgCl2 at 0.1 mM concentration but inhibited with increasing concentration. Not affected by carbohydrates such as fucose, galactose and glucose but displays a slight decrease in activity up to 25% with lactose, alpha-mannose and N-acetyl-galactosamine (GalNAc). Ref.1
Detected in dry seeds and cotyledons. Ref.1
Activity levels increase 5-9 days after imbibition in the hypocotyls and within 3-9 days in the roots. Detected in dry seeds but increased levels observed 5 days after seed imbibition. Ref.1
KM=2.59 mM for pNP-GlcNAc Ref.1
KM=2.94 mM for pNP-GalcNAc
Vmax=18.4 µmol/min/mg enzyme with pNP-GlcNAc as substrate
Vmax=2.73 µmol/min/mg enzyme with pNP-GalcNAc as substrate
Optimum pH is 5.0 with pNP-GlcNAc and 4.0 with pNP-GalNAc. Half maximal activity observed at pH 3.0 and 6.5 with pNP-GlcNAc and at pH 2.5 and 5.5 with pNP-GalNAc. Retains over 90% of its activity between pH 6.5-8.0 with pNP-GlcNAc, and between pH 6.0-7.5 with pNP-GalNAc.
Optimum temperature is 50 degrees Celsius toward pNP-GlcNAc and 60 degrees Celsius toward pNP-GalNAc. Displays activity higher than 50% between 35-70 degrees Celsius. Stable under 30 degrees Celsius. Ref.1
Sequence annotation (Features)
|||"beta-N-Acetylhexosaminidase involvement in alpha-conglutin mobilization in Lupinus albus."|
Santos C.N., Alves M., Oliveira A., Ferreira R.B.
J. Plant Physiol. 170:1047-1056(2013) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE, FUNCTION, CATALYTIC ACTIVITY, ENZYME REGULATION, BIOPHYSICOCHEMICAL PROPERTIES, TISSUE SPECIFICITY, DEVELOPMENTAL STAGE, GLYCOSYLATION.
|Accession||Primary (citable) accession number: B3EWR5|
|Entry status||Reviewed (UniProtKB/Swiss-Prot)|
|Annotation program||Plant Protein Annotation Program|
Classification of glycosyl hydrolase families and list of entries