Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.22.32 (
bromelain
)
1,025
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
To investigate the molecular basis of the low-pH-mediated interaction of the
bromelain
-solubilized ectodomain of influenza virus hemagglutinin (BHA) with membranes, we have photolabeled BHA in the presence of liposomes with the two carbene-generating, membrane-directed reagents 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine ([125I]TID) and a new analogue of a phospholipid, 1-palmitoyl-2-[11-[4-[3-(trifluoromethyl)diazirinyl]phenyl][2-3H] undecanoyl]-sn-glycero-3-phosphocholine ([3H]-PTPC/11). With the latter reagent, BHA was labeled in a strictly pH-dependent manner, i.e., at pH 5 only, whereas with [125I]TID, labeling was seen also at pH 7. In all experiments, the label was selectively incorporated into the BHA2 polypeptide, demonstrating that the interaction of BHA with membranes is mediated through this subunit, possibly via its hydrophobic N-terminal segment. Similar experiments with a number of other water-soluble proteins (ovalbumin, carbonic anhydrase,
alpha-lactalbumin
, trypsin, and soybean trypsin inhibitor) indicate that the ability to interact with liposomes at low pH is not a property specific for BHA but is observed with other, perhaps most, proteins.
...
PMID:Hydrophobic photolabeling identifies BHA2 as the subunit mediating the interaction of bromelain-solubilized influenza virus hemagglutinin with liposomes at low pH. 337 34
Soy-derived proteins (soy protein isolate, glycinin, and beta-conglycinin) and bovine whey-derived proteins (whey protein isolate,
alpha-lactalbumin
, beta-lactoglobulin) were hydrolyzed using subtilisin Carlsberg, chymotrypsin, trypsin,
bromelain
, and papain. The (in)solubility of the hydrolysates obtained was studied as a function of pH. At neutral pH, all soy-derived protein hydrolysates, particularly those from glycinin, obtained by hydrolysis with subtilisin Carlsberg, chymotrypsin,
bromelain
, and papain showed a stronger aggregation compared to the non-hydrolyzed ones. This increase in aggregation was not observed upon hydrolysis by trypsin. None of the whey-derived protein hydrolysates exhibited an increase in aggregation at neutral pH. The high abundance of theoretical cleavage sites in the hydrophobic regions of glycinin probably explains the stronger exposure of hydrophobic groups than for the other proteins, which is suggested to be the driving force in the aggregate formation.
...
PMID:Comparison of the aggregation behavior of soy and bovine whey protein hydrolysates. 1785 38