Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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Drug
Enzyme
Compound
Query: EC:3.4.22.6 (
chymopapain
)
407
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In three cases in which chemonucleolysis with
chymopapain
was used for the treatment of back and sciatic pain, gas from the vacuum phenomenon of a degenerated lumbar intervertebral disc was recovered. In one of these, the gas analyzed by gas chromatography contained 90%--92%
nitrogen
.
...
PMID:Analysis of gas in vacuum lumbar disc. 41 44
1. 2-(N'-Acetyl-L-phenylalanylamino)ethyl 2'-pyridyl disulphide [compound (III)] and 2-(acetamido)ethyl 2'-pyridyl disulphide [compound (IV)] were synthesized by acylation of the common intermediate, 2-aminoethyl 2'-pyridyl disulphide, to provide examples of chromogenic thiol-specific substrate-derived two-protonic-state electrophilic probe reagents. These two reagents, together with n-propyl 2-pyridyl disulphide [compound (II)], provide structural variation in the non-pyridyl part of the molecule from a simple hydrocarbon side chain in compound (II) to a P1-P2 amide bond in compound (IV) and further to both a P1-P2 amide bond and a hydrophobic side chain (of phenylalanine) at P2 as a potential occupant of S2 subsites. 2. These disulphides were used as reactivity probes to investigate specificity and binding-site-catalytic-site signalling in a number of cysteine proteinases by determining (a) the reactivity at pH 6.0 at 25 degrees C at I 0.1 of compound (III) (a close analogue of a good papain substrate) towards 2-mercaptoethanol, benzimidazol-2-ylmethanethiol [compound (V), as a minimal catalytic-site model], chymopapains B1-B3,
chymopapain A
, papaya proteinase omega, actinidin, cathepsin B and papain, (b) the effect of changing the structure of the probe as indicated above on the reactivities of compound (V) and of the last five of these enzymes, and (c) the forms of pH-dependence of the reactivities of papain and actinidin towards compound (III). 3. The kinetic data suggest that reagents of the type investigated may be sensitive probes of molecular recognition features in this family of enzymes and are capable not only of detecting differences in binding ability of the various enzymes but also of identifying enzyme-ligand contacts that provide for binding-site-catalytic-site signalling mechanisms. 4. The particular value of this class of probe appears to derive from the possibility of activating the 2-mercaptopyridine leaving group not only by formal protonation, as was recognized previously [see Brocklehurst (1982) Methods Enzymol. 87C, 427-469], but also by hydrogen-bonding to the pyridyl
nitrogen
atom when the appropriate geometry in the catalytic site is provided by enzyme-ligand contacts involving the non-pyridyl part of the molecule.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Substrate-derived two-protonic-state electrophiles as sensitive kinetic specificity probes for cysteine proteinases. Activation of 2-pyridyl disulphides by hydrogen-bonding. 366 11
A procedure for universal 13C and/or 15N labeling of microbial peptides which are produced by fermentation in complex media and its application to two food-preserving bacteriocins from lactic acid bacteria are described. Isotopic enrichment of nisin A (from Lactococcus lactis) and of leucocin A (from Leuconostoc gelidum) is readily achieved using a soluble peptone derived from enzymatic hydrolysis (pepsin and
chymopapain
) of Anabaena sp. ATCC 27899 cells grown on sodium [13C]bicarbonate and/or sodium [15N]nitrate as sole carbon and
nitrogen
sources. Combustion of this peptone followed by mass spectrometric analysis indicates that 45% of the labeled carbon and 65% of the labeled
nitrogen
added to the Anabaena culture are utilized in the amino acids of the peptone and that the isotopic purity for both 13C and 15N remains essentially unchanged provided that the cells are grown under argon atmosphere to avoid
nitrogen
fixation. NMR analyses of [13C,15N]nisin A using H[13C]MQC, H[13C]MBC, 2D INADEQUATE, and H[15N]MQC techniques confirmed 1H spectral assignments previously reported for unlabeled material and readily provided carbon and
nitrogen
assignments. The results show that universal but not uniform 13C labeling occurs unless the nutrient source is completely isotopically enriched at high level (> or = 98%) because of differential levels of de novo amino acid synthesis. Application of NMR techniques such as TOCSY, DQF-COSY, NOESY, and H[13C]MQC to unlabeled and [13C]leucocin A afforded the complete 1H and 13C assignment. Leucocin A does not possess clearly defined conformational structure in DMSO or aqueous solutions.
...
PMID:15N- and 13C-labeled media from Anabaena sp. for universal isotopic labeling of bacteriocins: NMR resonance assignments of leucocin A from Leuconostoc gelidum and nisin A from Lactococcus lactis. 841 50
In defoliated grasses, where photosynthesis is reduced due to removal of leaf material, it is well established that remobilization of
nitrogen
occurs from both older remaining leaves and roots towards the younger growing leaves. In contrast, little is known about the movement of
nitrogen
within intact grass plants experiencing prolonged inhibition of photosynthesis. We tested the following hypotheses in Festuca rubra L. ssp. rubra cv. Boreal: that both reduction of the atmospheric CO2 concentration and defoliation (1) induce mobilization of
nitrogen
from roots and older leaves towards growing leaves and (2) elicit similar directional change in the abundance of proteins in roots and older leaves relevant to the process of
nitrogen
mobilization including, glutamine synthetase (GS), EC 6.3.1.2; papain, EC 3.4.22.2;
chymopapain
,
EC 3.4.22.6
; ribulose bisphosphate carboxylase/oxygenase (Rubisco), EC 4.1.1.39; and the light harvesting complex of photosystem II (LHCPII). After growth at ambient atmospheric CO2 concentration, plants of F. rubra were subject to atmospheres containing either ambient (350 micro l l-1) or deplete (< 20 micro l l-1) CO2. Concurrently, plants were either left intact or defoliated on one occasion. Steady state 15N labelling coupled with a series of destructive harvests over a 7-day period enabled changes in the
nitrogen
dynamics of the plants to be established. Proteins pertinent to the process of
nitrogen
mobilization were quantified by immunoblotting. Irrespective of defoliation, plants in ambient CO2 mobilized
nitrogen
from older to growing leaves. This mobilization was inhibited by deplete CO2. Greater concentration of Rubisco and reduced
chymopapain
abundance in older remaining leaves of intact plants, in deplete compared with ambient CO2, suggested the inhibition of mobilization was due to inhibition of protein degradation, rather than to the export of degradation products. Both deplete CO2 and defoliation induced
nitrogen
mobilization from roots to growing leaves. In plants at ambient CO2, defoliation did not affect
nitrogen
uptake or its allocation. Therefore in F. rubra
nitrogen
mobilization can occur independently of any downregulation of
nitrogen
uptake. This suggests either different signal compounds may act to downregulate uptake and upregulate mobilization, or if one particular signalling compound is used its concentration threshold differs for induction of mobilization and downregulation of uptake. The abundance of the cysteine proteases papain and
chymopapain
was low in roots suggesting that they were not involved in protein degradation in this tissue.
...
PMID:Reduced atmospheric CO2 inhibits nitrogen mobilization in Festuca rubra. 1220 63