Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The production, purification and analysis of peptide derived by digestion of mitochondrial aspartate aminotransferase with thermolysin and chymotrypsin are described. Despite the complexity of the peptide mixture obtained and the relative shortness of the fragments produced, these digests proved to be very useful for the completion of the primary structure determination of the enzyme. In fact, information for 87% of the total structure was contributed by thermolytic peptides, and for 89% by the chymotryptic ones. Moreover some of these peptides were essential for elucidating controversial points of the sequence.
 ...
PMID:The primary structure of mitochondrial aspartate aminotransferase from pig heart: peptides obtained by cleavage with thermolysin and chymotrypsin. 55 5

1. Crude extracts of Limulus CNS cause hyperglycemia in Orconectes immunis and expand chromatophores in Uca pugilator. 2. The hyperglycemic action is due to a previously unknown polypeptide (LHGF) with an estimated molecular weight of 6400 daltons. LHGF is inactivated by hydrogen peroxide, pepsin, and protease, but unaffected by trypsin and brief boiling.3. The chromatophorotropic activity is due to the previously reported substance, LUC. LUC is shown to be a peptide with an approximate molecular weight of 1850 daltons; it is inactivated by hydrogen peroxide, protease, pepsin, trypsin, chymotrypsin, and thermolysin. 4. LUC and LHGF activity can be readily separated by gel filtration on a Sephadex G-25 column. 5. The similarity of LUC and LHGF to known crustacean hormones is dicussed.
 ...
PMID:Separation and partial purification of central nervous system peptides from Limulus polyphemus with hyperglycemic and chromatophorotropic activity in crustaceans. 62 59

Protein S21 was digested with trypsin before and after maleylation, with chymotrypsin, thermolysin and a glutamyl-specific protease. The resulting peptides were isolated and their amino acid composition determined. The amino acid sequences of selected peptides were determined either by the manual subtractive Edman method or by the dansyl-Edman procedure. Additional information was obtained from the automatic Edman degradation of the whole protein in a modified Sequenator. All these results combined yielded the sequence shown in Fig. 1. Protein S21 consists of 70 amino acids (Asp1,Asn2,Thr3,Ser2,Glu8,Pro3,Gly1,Ala9,Val6,Cys1,Ile1,Leu4,Tyr2,Phe3,His1,Lys9 and Arg14). It contains neither Met nor Trp. The molecular weight amounts to 8359. Clustering of basic amino acids is observed in five regions. We also include a prediction for regions with alpha-helices and with beta-sheets.
 ...
PMID:Determination of the complete amino acid sequence of protein S21 from Escherichia coli ribosomes. 76 57

The complete amino acid sequence of ribosomal protein L34 has been established by improved micro techniques with 3 mg of the lyophilized protein. The protein was digested with trypsin, thermolysin and chymotrypsin and the resulting peptides were isolated from fingerprints performed on cellulose thin-layer plates. The amino acid sequences of the peptides were determined by the combined micro dansyl-Edman technique using 5 - 10 nmol per sample. Aspartic acid and glutamic acid were distinguished from their amides by use of the color reaction of ninhydrin with the respective amino acid phenylthiohydantoins.
 ...
PMID:The sequence determination of a protein in a micro scale: the sequence analysis of ribosomal protein L34 of Escherichia coli. 78 33

The complete amino acid sequence of phosphlipase A2 (EC 3.1.1.4) from horse pancreas was determined. The protein controls of a single polypeptide chain of 125 amino acids and has a molecular weight of 13,927. The chain is crosslinked by seven disulfide bridges. The sequence was determined by automated Edman degradation of the intact protein and several of the large peptide fragments. Smaller peptides were analyzed by manual Edman degradation. Fragmentation of the peptide chain was accomplished by enzymatic digestion with trypsin, chymotrypsin, and thermolysin. The final overlap was found by digestion of the polypeptide with a staphylococcal protease specific for glutamoyl bonds. Phospholipase A2 from horse pancreas shows homology to snake venom phospholipases A2 and to the enzyme from porcine pancreas, provided that the published amino acid sequence of the porcine phospholipase A2 is revised to some extent.
 ...
PMID:Amino acid sequence of phospholipase A2 from horse pancreas. 83 12

The alfalfa mosaic virus protein was submitted to the action of cyanogen bromide. Four peptides were isolated. Study of these peptides allowed us to determine the order. Then protein was submitted, after S-carboxymethylation or S-aminoethylation, to the action of different proteolytic enzymes: trypsin, chymotrypsin, thermolysin and papain. The peptides issued from these different hydrolysis were separated on Dowex 50 X4 and Dowex 1 X2, and their amino acid composition was determined. The use of classical methods of sequence determination, of mass spectrometry and for one case the use of a sequencer, lead to the obtention of the primary structure of all the tryptic peptides. The studies of chymotryptic, thermolytic and papainic hydrolysates, and of cyanogen bromide rupture, allowed us to isolate the overlapping peptides which were necessary for the reconstitution of the complete proteic chain.
 ...
PMID:[Determination of the primary structure of alfalfa mosaic virus (strain S) coat protein. II. Complete sequence of the protein (author's transl)]. 88 29

Myoglobin isolated from skeletal muscle of the platypus contains 153 amino acid residues. The complete amino acid sequence has been determined following cleavage with cyanogen bromide and further digestion of the four fragments with trypsin, chymotrypsin, pepsin and thermolysin. Sequences of the purified peptides were determined by the dansyl-Edman procedure. The amino acid sequence showed 25 differences from human myoglobin and 24 from kangaroo myoglobin. Amino acid sequences in myoglobins are more conserved than sequences in the alpha- and beta-globin chains, and platypus myoglobin shows a similar number of variations in sequence to kangaroo myoglobin when compared with myoglobin of other species. The date of divergence of the platypus from other mammals was estimated at 102 +/- 31 million years, based on the number of amino acid differences between species and allowing for mutations during the evolutionary period. This estimate differs widely from the estimate given by similar treatment of the alpha- and beta-chain sequences and a constant rate of mutation of globin chains is not supported.
 ...
PMID:Studies on monotreme proteins. VII. Amino acid sequence of myoglobin from the platypus, Ornithoryhynchus anatinus. 96 22

The antitumor protein actinoxanthin exhibits high inhibitory activity against a number of gram-positive bacteria and some strains of transplantable leucoses and related tumors. Actinoxanthin was shown to consist of a single polypeptide chain crosslinked by two disulfide bonds and to contain 107 amino acid residues. Reduced and alkylated actinoxanthin was digested with chymotrypsin, thermolysin and trypsin. Based on the sequence analysis of fragments so obtained the complete amino acid sequence and the location of disulfide bonds of actinoxanthin has been proposed. The high degree homology of some regions of actinoxanthin and the antitumor protein neocarzinostatin have been revealed.
 ...
PMID:Chemical studies on actinoxanthin. 99 23

Preliminary studies have suggested that in Hb Dakar, histidine alpha112 was substituted by a glutamine. A re-investigation on this hemoglobin is presented in this report. A structural study has been performed using a new approach to analyse the tryptic core region of the human hemoglobin alpha chain. After tryptic digestion of the aminoethylated alpha chain, a secondary digestion of the tryptic core was carried out with chymotrypsin and with another protease, thermolysin. Analyses of the chymotryptic and thermolytic peptides indicated that the structure of Hb Dakar was identical to that of Hb Grady previously described by Huisman et al. who showed the insertion of three amino acid residues in position alpha115 or alpha118. The insertion, which was localized near two residues involved in the alpha1beta1 contact, did not produce a dissociation into dimers. Functional studies demonstrated a a slightly increased oxygen affinity, a lowered cooperativity and a normal Bohr effect. The low amount of the abnormal hemoglobin (8%) may in part be explained by a slight instability of the molecule.
 ...
PMID:Hemoglobin Dakar = Hb Grady: demonstration by a new approach to the analysis of the tryptic core region of the alpha chain and oxygen equilibrium properties. 99 99

The amino acid sequence of the coenzyme-binding site of serine transhydroxymethylase from rabbit liver has been determined. After reduction with NaBH4 and aminoethylation, a first sample of enzyme was digested with thermolysin and a single phosphopyridoxyl peptide was isolated. A second sample of similarly treated enzyme was digested with chymotrypsin and three phosphopyridoxyl peptides clearly originating from a unique coenzyme-binding site were isolated. Sequence analysis of these peptides indicate the following structure: Val-Val-Thr-Thr-His(Pxy)-Thr-Leu. Sequence homologies of the active site of various pyridoxalphosphate enzymes are discussed in terms of a possible catalytic role and of evolution of this class of proteins.
 ...
PMID:Serine transhydroxymethylase from rabbit liver. Sequence of anonapeptide at the pyridoxal-5'-phosphate-binding site. 100 37


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>