Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.27 (thermolysin)
 1,894 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Some proteases, i.e. trypsin, alpha-chymotrypsin, thermolysin, proteinase K, alpha-amylase, collagenase, and papain were investigated on their effect on isolated zonular fibers. All these enzymes but collagenase were zonulolytic active. An attack on the ground substance of the fibers by substances solving glycosaminoglycans and proteoglycans (hyaluronidase, EDTA, guanidinium chloride, H2O2) showed an increased effect of the enzymes used. These results suggest that the interfibrillar matrix has a protective function on the zonular fibers.
 ...
PMID:[The attack of different proteases on isolated zonular fibers (author's transl)]. 13 75

Benzoyl- and isopentenoyl phosphoric triamides (BPA and IPA) strongly inhibited urease activities from jack bean, soybean, watermelon seed, Proteus mirabilis, P. rettgeri, P. vulgaris, Mycobacterium smegmatis, and Ureaplasma urealyticum. Their I50 values (the final concentration causing 50% inhibition), independent of enzyme source, were 2-21 nM, which are about 1,000-fold lower than that of caprylohydroxamic acid, one of the most potent urease inhibitors. ATP-urea amidolyase activity was inhibited 50% by BPA at a higher concentration of 0.28 mM, but was not affected by IPA even at 1.3 mM. Thirteen kinds of hydrolases (trypsin, chymotrypsin, thermolysin, leucine aminopeptidase, papain, lipase, alpha-amylase, glucuronidase, asparaginase, arylsulfatase, alkaline phosphatase, acid phosphatase, and true cholinesterase), two oxidoreductases (catalase and alcohol dehydrogenase), three transferases (glutamic-oxaloacetic aminotransferase, gamma-glutamyl transpeptidase, and arylsulfotransferase) and two kinases (pyruvate kinase and creatine kinase) were not affected at all even at 1 mM BPA and IPA. Exceptionally, pseudo-cholinesterase from human serum was inhibited by BPA and IPA, whose I50 values were 70 nM and 10 muM, respectively, using acetylthiocholine as a substrate. These values increased to 0.55 muM and 54 muM, respectively, when acetylcholine was used as a substrate. These results show that N-acylphosphoric triamides potently and specifically inhibit urease activity at concentrations of nM order.
 ...
PMID:Specific inhibition of urease by N-acylphosphoric triamides. 384 42

The amino acid sequence of a protein alpha-amylase inhibitor from Streptomyces griseosporeus YM-25 (Haim II), which consists of 77 amino acid residues, including two disulfide bridges, was determined by conventional methods. One of the disulfide bridges was found to be located between Cys(6) and Cys(22), and the other between Cys(40) and Cys(67) from the results of structure analyses of the two cystine-containing peptides obtained from the thermolysin digest of the native inhibitor.
 ...
PMID:Amino acid sequence of protein alpha-amylase inhibitor from Streptomyces griseosporeus YM-25. 387 8

The native and oxidized alpha-amylase inhibitor Z-2685, isolated from the culture medium of Streptomyces parvullus FH-1641, and its overlapping cleavage products were degraded by the automatic Edman technique. Digestion was carried out with pepsin, thermolysin and trypsin. The alpha-amylase inhibitor is a polypeptide consisting of 76 amino acids with a molecular mass of 8 129 Da. With the exception of methionine and lysine, all naturally occurring amino acids are present. It is interesting that identical regions exist, in particular the sequence Trp-Arg-Tyr common to all four known microbial inhibitor sequences. We believe that the side chains of these three amino acids are important for interacting with the alpha-amylase molecule. Computer alignment enabled us to show a possible binding region in the alpha-amylase molecule which might react with the inhibitors. Furthermore, homology exists to mammalian alpha-amylases. This result is explained by the assumption that the inhibitor evolved from a duplication of the original gene of the enzyme.
 ...
PMID:The primary structure of alpha-amylase inhibitor Z-2685 from Streptomyces parvullus FH-1641. Sequence homology between inhibitor and alpha-amylase. 387 77

Oxygen does not quench the luminescence of either free Tb or of Tb bound to dipicolinate. However, sensitized Tb luminescence in complexes of that ion with elastase, thermolysin, and alpha-amylase is quenched by oxygen at rates that far exceed that with which the intrinsic fluorescence of the proteins is quenched. We infer that this more rapid quenching of Tb luminescence indicates a major role for energy transfer from tryptophan moieties in a triplet excited state.
 ...
PMID:Oxygen quenching of sensitized terbium luminescence in complexes of terbium with small organic ligands and proteins. 618 34

Gluten from the wheat variety Rektor was extracted with 70% aqueous ethanol. The insoluble portion (whole glutenin) was partially hydrolysed with trypsin at pH 6.5 and separated on a Sephadex G25 column. The high molecular weight fraction 1 was further hydrolysed with pepsin at pH 2.0. To remove low molecular weight proteins, a portion of whole glutenin was extracted with dilute acetic acid. The residue (enriched glutenin), which contained mostly LMW and HMW subunits of glutenin, was hydrolysed with thermolysin at pH 6.5. The peptic and tryptic hydrolysates were separated on a Sephadex G25 column and the peptide fractions with the highest cystine content were separated further by reversed-phase high-performance liquid chromatography (RP-HPLC). Cystine peptides were detected by differential chromatography (RP-HPLC prior to and after reduction of disulphide bonds) and then isolated by preparative RP-HPLC. After reduction, cysteine peptides were alkylated and analysed for their amino acid sequence. Altogether, 19 cystine peptides were characterized and assigned to known sequences of gluten proteins; 16 peptides confirmed the positions of disulphide bonds present in LMW subunits and gamma-gliadins, as described previously. For the first time, a cystine peptide has been isolated, representing an intermolecular disulphide bond between the y-type of HMW and LMW subunits. Furthermore, a cystine peptide was assigned to gamma-gliadins; thus, all cysteine residues of gamma-gliadins are documented by at least one cystine peptide. One peptide analysed came from the alpha-amylase inhibitor CM 16. Altogether the results indicate that the intramolecular linkages of gluten proteins are not formed at random, but are strongly directed.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Disulphide bonds in wheat gluten: cystine peptides derived from gluten proteins following peptic and thermolytic digestion. 766 61

The shore crab Hemigrapsus sanguineus hemolymph contains soluble proteins that bind tetrodotoxin (TTX) and are responsible for high resistance of the crab to TTX. The TTX-binding protein was purified from the hemolymph by ultrafiltration, lectin affinity chromatography and gel filtration HPLC. The purified protein gave only one band in native-polyacrylamide gel electrophoresis (PAGE), confirming its homogeneity. Its molecular weight was estimated to be about 400k by gel filtration HPLC, while it was estimated to be about 82k under non-reducing conditions and about 72 and 82k under reducing conditions by SDS-PAGE, indicating that the TTX-binding protein was composed of at least two distinct subunits. The TTX-binding protein was an acidic glycoprotein with pI 3.5, abundant in Asp and Glu but absent in Trp, and contained 6% reducing sugar and 12% amino sugar. The protein selectively bound to TTX, with a neutralizing ability of 6.7 mouse unit TTX/mg protein, but not to paralytic shellfish poisoning toxins. However, its neutralizing activity was almost lost by treatments with enzymes (protease XIV, thermolysin, trypsin, amyloglucosidase and alpha-amylase) and denaturing agents (1% SDS, 1% dithiothreitol, 8 M urea and 6 M guanidine hydrochloride), suggesting the involvement of both proteinaceous and sugar moieties in the binding to TTX and the importance of the steric conformation of the TTX-binding protein.
 ...
PMID:A tetrodotoxin-binding protein in the hemolymph of shore crab Hemigrapsus sanguineus: purification and properties. 1217 12

Schizolobium parahyba chymotrypsin inhibitor (SPCI) was completely purified as a single polypeptide chain with two disulfide bonds, by TCA precipitation and ion exchange chromatography. This purification method is faster and more efficient than that previously reported: SPCI is stable from pH 2 to 12 at 25 degrees C, and is highly specific for chymotrypsin at pH 7-12. It weakly inhibits elastase and has no significant inhibitory effect against trypsin and alpha-amylase. SPCI is a thermostable protein and resists thermolysin digestion up to 70 degrees C.
 ...
PMID:Purification and pH stability characterization of a chymotrypsin inhibitor from Schizolobium parahyba seeds. 1508 Dec 78

Detailed circular dichroism (CD), scattering and quenching studies, 1-anilinonaphthalene-8-sulfonate (ANS) binding, irreversible thermoinactivation, activity measurements and proteolytic digestion of bacterial alpha-amylases have been carried out to elucidate the effect of trifluoroethanol (TFE) on the structure of these enzymes. Under high concentrations of TFE both of the alpha-amylases, a thermostable alpha-amylase from Bacillus licheniformis (BLA) and its mesophilic counterpart from Bacillus amyloliquefaciens (BAA), acquire partially folded state characterized by an enhanced content of the secondary structure (helix) and reduced tertiary structures. According to ANS binding studies, we suggest that the TFE states induced by TFE/water mixture are not the molten globule state in the alpha-amylase folding pathway. In addition, data shows significant reversible aggregation of both enzymes in TFE/water mixtures with concentration between 10 and 60% (v/v). However, reversibility is more in case of BAA. As expected, in the absence of TFE, the thermophilic enzyme compared to mesophilic enzyme, shows a greater resistance to digestion by thermolysin. With respect to fluorescence quenching by acrylamide and potassium iodide, the thermophilic enzyme, BLA, is characterized by higher structural flexibility as compared to the BAA. On the other hand, in the presence of TFE, the enzymes are digested by protease to produce large protein fragments. It is proposed that highly helical secondary structures, acquired by BAA and BLA when dissolved in aqueous TFE, prevent binding and adaptation of the protein substrate at the active site of the protease.
 ...
PMID:Comparative studies on trifluoroethanol (TFE) state of a thermophilic alpha-amylase and its mesophilic counterpart: limited proteolysis, conformational analysis, aggregation and reactivation of the enzymes. 1522 89

The most abundant alpha-amylase (EC 3.2.1.1) in shoots and cotyledons from pea (Pisum sativum L.) seedlings was purified 6700-and 850-fold, respectively, utilizing affinity (amylose and cycloheptaamylose) and gel filtration chromatography and ultrafiltration. This alpha-amylase contributed at least 79 and 15% of the total amylolytic activity in seedling cotyledons and shoots, respectively. The enzyme was identified as an alpha-amylase by polarimetry, substrate specificity, and end product analyses. The purified alpha-amylases from shoots and cotyledons appear identical. Both are 43.5 kilodalton monomers with pls of 4.5, broad pH activity optima from 5.5 to 6.5, and nearly identical substrate specificities. They produce identical one-dimensional peptide fingerprints following partial proteolysis in the presence of SDS. Calcium is required for activity and thermal stability of this amylase. The enzyme cannot attack maltodextrins with degrees of polymerization below that of maltotetraose, and hydrolysis of intact starch granules was detected only after prolonged incubation. It best utilizes soluble starch as substrate. Glucose and maltose are the major end products of the enzyme with amylose as substrate. This alpha-amylase appears to be secreted, in that it is at least partially localized in the apoplast of shoots. The native enzyme exhibits a high degree of resistance to degradation by proteinase K, trypsin/chymostrypsin, thermolysin, and Staphylococcus aureus V8 protease. It does not appear to be a high-mannose-type glycoprotein. Common cell wall constituents (e.g. beta-glucan) are not substrates of the enzyme. A very low amount of this alpha-amylase appears to be associated with chloroplasts; however, it is unclear whether this activity is contamination or alpha-amylase which is integrally associated with the chloroplast.
 ...
PMID:Characterization of alpha-Amylase from Shoots and Cotyledons of Pea (Pisum sativum L.) Seedlings. 1666 84


1