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Compound
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Query: UNIPROT:P01034 (
cystatin C
)
3,397
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A cysteine protease inhibitor was purified from total membrane fractions of an invasive murine hepatoma, Hepa cl 9. On gel filtration under non-reducing conditions the purified inhibitor was eluted in a single peak of M(r) 10-15 kDa, but resolved as two bands at 14 and 70 kDa on SDS-PAGE under reducing conditions. By isoelectric focusing, the inhibitor ran at an isoelectric point of 4.75. Immunoblotting studies using the enhanced chemiluminescence technique indicated no crossreactivity with monoclonal antibodies to stefin B and
cystatin C
or with a polyclonal antibody to low M(r) kininogen. In contrast, the 14 kDa and 70 kDa bands both crossreacted with a polyclonal antibody to
stefin A
, suggesting that the cysteine protease inhibitor associated with Hepa cl 9 membranes may be a modified form of
stefin A
.
...
PMID:A membrane-associated cysteine protease inhibitor from murine hepatoma. 151 98
Papaya proteinase IV (PPIV) is not inhibited by chicken cystatin, or human cystatins A or C, unlike most other proteinases of the papain superfamily. The enzyme inactivates chicken cystatin and human
cystatin C
by limited proteolysis of the glycyl bond previously shown to be involved in the inhibitory inactivity of the cystatins, but has no action on
cystatin A
. Contamination of commercial crystalline papain with PPIV accounts for the limited proteolysis of cystatins by 'papain' reported previously. PPIV is slowly bound by human alpha 2-macroglobulin. The enzyme is irreversibly inactivated by E-64, and by peptidyl diazomethanes containing glycine in P1 and a hydrophobic side-chain in P2. The reaction of PPIV with iodoacetate is extremely slow. PPIV is inhibited by peptide aldehydes despite the presence of bulky sidechains in P1, suggesting that these reversible inhibitors do not bind as substrate analogues.
...
PMID:Interactions of papaya proteinase IV with inhibitors. 169 Jun 69
Cysteine proteinase inhibitors (CpI) of all three families were found in ascites fluid from patients with ovarian carcinoma. CPIs were isolated by affinity chromatography on carboxymethylated papain Sepharose, followed by gel filtration, anti-stefin-Sepharose and ion exchange chromatography. The highest apparent inhibition against cathepsin B (Cat B) was found in the low molecular mass (LMM) CPI fraction. Immunochemical analysis of this fraction revealed the presence of
cystatin C
and both stefins A and B while the high molecular mass (HMM) CPI fraction contained kininogens. We demonstrated that CPIs were not completely associated with cysteine proteinases (CPs): about 20% of HMM CPIs and 50% of LMM CPIs were free in native ascites fluid. Affinity chromatography on anti-Cat B-Sepharose revealed that the major LMM CPI, associated with Cat B in native ascites fluid, was the full length form of
cystatin C
, pI 9.3, and not its truncated form, pI 7.85. The latter was isolated and found to inhibit Cat B in vitro with apparent Ki 0.18 +/- 0.2 nM. Stefin A was isolated from alkaline activated ascites fluid in its two isoforms, pI 4.6 and 4.9. In native ascites, the pI 4.9 isoform was mostly associated with Cat B. Ki for Cat B was 3.55 +/- 1.7 nM, not significantly different from the Ki values measured for
stefin A
, isolated from other human tissues and biological fluids.
...
PMID:Cystatins and stefins in ascites fluid from ovarian carcinoma. 173 49
The gene for the human cysteine proteinase inhibitor
stefin A
(STF1), alias
cystatin A
, has been mapped to chromosome 3, using the polymerase chain reaction to specifically amplify the human
stefin A
sequence in human-hamster hybrid DNA. STF1 is further sublocalized to regions between centromere and 3q21 using a deletion mapping panel for this chromosome. This assignment shows that
stefin A
is not syntenic with
cystatin C
which has been localized to chromosome 20.
...
PMID:Mapping of the gene for human cysteine proteinase inhibitor stefin A, STF1, to chromosome 3cen-q21. 200 63
We have examined the amino acid sequences of a number of proteins that have been suggested to be related to chicken cystatin, a protein from chicken egg white that inhibits cysteine proteinases. On the basis of statistical analysis, the following proteins were found to be members of the cystatin superfamily: human
cystatin A
, rat
cystatin A
(alpha), human cystatin B, rat cystatin B(beta), rice cystatin, human
cystatin C
, ox colostrum cystatin, human cystatin S, human cystatin SA, human cystatin SN, chicken cystatin, puff adder cystatin, human kininogen, ox kininogen, rat kininogen, rat T-kininogens 1 and 2, human alpha 2HS-glycoprotein, and human histidine-rich glycoprotein. Fibronectin is shown not to be a member of this superfamily, and the c-Ha-ras oncogene protein p21 (Val-12) probably is not a member also. It was convenient to divide members of the superfamily into four types on the basis of the presence of one, two, or three copies of cystatin-like segments and the presence or absence of disulfide bonds. Evolutionary dendrograms were calculated by three methods, and from these we have constructed a scheme depicting the sequence of events in the evolution of these proteins. We suggest that about 1000 million years ago a precursor containing disulfide loops appeared, and that all disulfide-containing cystatins are derived from this. We follow the evolution of the proteins of the superfamily along four main lineages, with special attention to the part that duplication of segments has played in the development of the more complex molecules.
...
PMID:Evolution of proteins of the cystatin superfamily. 210 24
Sputum samples from 25 patients with bronchiectasis were assayed enzymatically for myeloperoxidase, neutrophil elastase and cathepsin B, and immunologically for
cystatin A
, cystatin B,
cystatin C
, cystatin S and kininogen. High myeloperoxidase and neutrophil elastase levels were found in those sputum samples that were assessed visually to be purulent. These samples were also found to contain high levels of cathepsin B activity and
cystatin A
, but low levels of cystatin S and of the most effective cathepsin B inhibitor,
cystatin C
. In contrast, sputum samples that were low in myeloperoxidase and neutrophil elastase activities had low levels of cathepsin B and
cystatin A
, but high
cystatin C
and S levels. It is concluded that cathepsin B activity in sputum is positively correlated with the degree of inflammation and neutrophil recruitment. Although this may be due in part to reduced amounts of cathepsin B inhibitors, particularly
cystatin C
, theoretical considerations suggest that factors other than the gross level of inhibitors must be involved in the control of cathepsin B activity.
...
PMID:Levels of neutrophil elastase and cathepsin B activities, and cystatins in human sputum: relationship to inflammation. 223 63
In the present work we demonstrate the presence of cysteine proteinase inhibitors of all three classes: kininogens,
stefin A
, and
cystatin C
, in inflamed human gingiva. Using
cystatin C
, in inflamed human gingiva. Using immunochemical methods we found that
stefin A
is the major inhibitor of cysteine proteinases, followed by kininogen and
cystatin C
. The values for
stefin A
and
cystatin C
ranged from 7.0--400 micrograms/g and 1.5--6.1 micrograms/g tissue, respectively, as determined by enzyme-linked immunosorbent assay in inflamed gingival homogenates from patients with different degrees of periodontal disease.
...
PMID:Cysteine proteinase inhibitors in inflamed human gingiva. 314 95
A purification procedure of cathepsin H from human kidney is presented. It includes gel filtration, ion exchange chromatography, and covalent chromatography on thiol Sepharose as an essential step. Purified cathepsin H emerges in an isoelectric focusing gel at pH 6.1 and 6.3. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate shows a molecular mass of about 28 kDa. Less than 20% of the enzyme preparation can be separated into a heavy (24 kDa) and a light chain (4 kDa) after reduction and gel filtration on Sephacryl S-200. The partial amino-acid sequence of human cathepsin H shows its close similarity to rat cathepsin H. Inhibition constants (Ki) of cathepsins H and B with chicken cystatin, two forms of human
stefin A
, human stefin B, and two forms of human
cystatin C
are in the range of 10(-9) to 10(-11)M.
...
PMID:A new purification procedure of human kidney cathepsin H, its properties and kinetic data. 320 63
Six cysteine proteinase inhibitors were isolated from human urine by affinity chromatography on insolubilized carboxymethylpapain followed by ion-exchange chromatography and immunosorption. Physicochemical and immunochemical measurements identified one as
cystatin A
, one as cystatin B, one as
cystatin C
, one as cystatin S, and one as low molecular weight kininogen. The sixth inhibitor displayed immunochemical cross-reactivity with salivary cystatin S but had a different pI (6.85 versus 4.68) and a different (blocked) N-terminal amino acid. This inhibitor was tentatively designated cystatin SU. The isolated inhibitors accounted for nearly all of the cysteine proteinase inhibitory activity of the urinary pool used as starting material. The enzyme inhibitory properties of the inhibitors were investigated by measuring inhibition and rate constants for their interactions with papain and human cathepsin B. Antisera raised against the inhibitors were used in immunochemical determinations of their concentrations in several biological fluids. The combined enzyme kinetic and concentration data showed that several of the inhibitors have the capacity to play physiologically important roles as cysteine proteinase inhibitors in many biological fluids. Cystatin C had the highest molar concentration of the inhibitors in seminal plasma, cerebrospinal fluid, and milk; cystatin S in saliva and tears; and kininogen in blood plasma, synovial fluid, and amniotic fluid.
...
PMID:Isolation of six cysteine proteinase inhibitors from human urine. Their physicochemical and enzyme kinetic properties and concentrations in biological fluids. 348 17
The cathepsins B, H and L of human origin were isolated in pure form in sufficient quantities for structural characterization. The complete amino acid sequence of human liver cathepsin B was determined. Partial amino acid sequences of the human kidney cathepsin H and L show the highly conserved region around the active site cysteine. The cysteine proteinase inhibitors
stefin A
, human stefin B and human
cystatin C
were isolated, characterized and sequenced. Their amino acid sequences are compared with sequences of other protein inhibitors of the stefin and cystatin family, showing a high degree of homology throughout both families. The stefin and cystatin family, together with newly discovered kininogen family belong to the same superfamily of cystatins. The constructed dendrogram shows that the most closely related inhibitors so far sequenced are human stefin B and rat liver TPI.
...
PMID:Human cysteine proteinases and their protein inhibitors stefins, cystatins and kininogens. 349 61
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