Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Photolabeling of the alpha-neuraminidase/beta-galactosidase complex in human placenta (Verheijen, F.W. et al (1987) Eur. J. Biochem. 162, 63-67) was carried out using the radioactive photoprobe, 9-S-(4-azido-3,5-3H-2-nitrophenyl)-5-acetamido-2,6 anhydro-2,3,5,9- tetradeoxy-9- thio-D-glycero-D-galacto-non-2-enonic acid. Two intensely labeled bands at 61 and 46 kD were detected with autoradiography. Labeling of the 46 kD protein was blocked with the inclusion of the surfactant Triton X-100 in the photolysis mixture, indicating a nonspecific, hydrophobic interaction. The 61 kD protein was protected from labeling only when the neuraminidase inhibitor 2,3 dehydro N-acetyl neuraminic acid (1 mM) was present during photolysis. These results suggest that the neuraminidase activity resides among the proteins in the 61 kD molecular weight range comigrating with the lysosomal beta-galactosidase, under denaturing conditions.
 ...
PMID:Photolabeling of the alpha-neuraminidase/beta-galactosidase complex from human placenta with a photoreactive neuraminidase inhibitor. 225 9

A cDNA clone corresponding to a portion of the catalytic subunit of calmodulin (CaM)-dependent phosphoprotein phosphatase (calcineurin) was isolated from a murine brain library by expression vector immunoscreening. A beta-galactosidase fusion protein that reacted on Western blots with anti-calcineurin antibodies and biotinylated CaM was purified in preparative amounts using CaM-Sepharose affinity chromatography. Partial digestion of the hybrid protein with Staphylococcus aureus V-8 protease produced several immunoreactive peptides that appeared identical to fragments generated from authentic brain calcineurin. The 1111-base-pair (bp) EcoRI insert contained an open reading frame encoding a protein of 35 kDa followed by a 190-bp 3' noncoding region; seven peptides obtained by partial amino acid sequencing of the bovine brain enzyme were found in the deduced sequence. A domain approximately 12 kDa from the carboxyl terminus was deduced to be the CaM-binding site based on consensus structural features and a sequence of seven amino acids highly related to smooth muscle myosin light-chain kinase. Two regions with identity to protein phosphatases 1 and 2A were found in the amino half of the cloned sequence; however, the intervening sequence contained apparent insertions, suggesting splicing of subdomains. Thus, the structure of calcineurin is chimeric, consisting of conserved catalytic elements and a regulatory CaM-binding domain.
 ...
PMID:Characterization of a cDNA clone encoding the calmodulin-binding domain of mouse brain calcineurin. 284 50

Venom from the pupal endoparasitoid, Pimpla hypochondriaca has previously been shown to contain a mixture of biologically active molecules. Currently, P. hypochondriaca venom was examined for the presence of hydrolase activity. Six hydrolases were consistently detected using the API ZYM semiquantitative colourimetric kit. The main hydrolases detected were; acid phosphatase, beta-glucosidase, esterase, beta-galactosidase, esterase lipase, and lipase. The most rapid and intense colour reaction was detected for acid phosphatase. The pH optimum and the specific activity of venom acid phosphatase was determined using p-nitrophenol phosphate as a substrate and were 4.8 and 0.47 nmol p-nitrophenol/min/microg of venom protein, respectively. The acid phosphatase activity was inhibited in a dose dependent manner by sodium fluoride (IC(50) 4.2 x 10(-4) M), and by cocktail inhibitor 2 (CI 2). P. hypochondriaca venom has previously been shown to display potent cytotoxic activity towards Lacanobia oleracea haemocytes maintained in vitro. The contribution of acid phosphatase in venom to this cytotoxic activity was investigated by titrating venom against CI 2 prior to the addition of L. oleracea haemocytes. The results suggest that, despite the relatively high levels of acid phosphatase activity in venom, venom acid phosphatase plays no role in the antihaemocytic activity of P. hypochondriaca venom in vitro.
 ...
PMID:Hydrolase activity in the venom of the pupal endoparasitic wasp, Pimpla hypochondriaca. 1593 65

The mechanism-based inhibitor 2,4-dinitrophenyl 2-deoxy-2-fluoro-beta-d-galactopyranoside (DNP2FGal) was used to inactivate the Family 42 beta-galactosidase (YesZ) from Bacillus subtilis via the trapping of a glycosyl-enzyme intermediate, thereby tagging the catalytic nucleophile in the active site. Proteolytic digestion of the inactivated enzyme and of a control sample of unlabeled enzyme, followed by comparative high-performance liquid chromatography and mass spectrometric analysis identified a labelled peptide of the sequence ETSPSYAASL. These data, combined with sequence alignments of this region with representative members of Family 42, unequivocally identify the catalytic nucleophile in this enzyme as Glu-295, thereby providing the first direct experimental proof of the identity of this residue within Family 42.
 ...
PMID:Identification of the catalytic nucleophile in Family 42 beta-galactosidases by intermediate trapping and peptide mapping: YesZ from Bacillus subtilis. 1748 82