RESUMO
A novel protein protease inhibitor (FPI-F) which is highly specific for fungal proteases and subtilisin was isolated from the silkworm hemolymph, and its amino acid sequence was determined by conventional methods. The inhibitor consisted of 55 amino acid residues and had a molecular weight of 6,100. The inhibitor included eight cysteine residues and relatively large amounts of acidic amino acids, but neither alanine, methionine nor tryptophan. The amino acid sequence of FPI-F was not homologous with those of other known protease inhibitors of microbe, plant or animal origin.
Assuntos
Bombyx/química , Proteínas de Insetos , Proteínas/isolamento & purificação , Sequência de Aminoácidos , Animais , Hemolinfa/química , Dados de Sequência Molecular , Peptídeos/química , Proteínas/química , Serina Endopeptidases/químicaRESUMO
The amino acid sequence of glutathione S-transferase a from guinea pig liver was determined. Glutathione S-transferase a was composed of two identical subunits, each comprising 218 amino acid residues. The amino acid sequence of glutathione S-transferase a exhibited 73% homology with that of human glutathione S-transferase Ha, 69% with that of rat glutathione S-transferase Ya, and 68% with that of rat glutathione S-transferase Yc, which are known to belong to class Alpha. From the above result, together with previous observations on its substrate specificity, it was concluded that glutathione S-transferase a belonged to class Alpha.
Assuntos
Glutationa Transferase/isolamento & purificação , Fígado/enzimologia , Sequência de Aminoácidos , Animais , Brometo de Cianogênio , Glutationa Transferase/classificação , Cobaias , Humanos , Dados de Sequência Molecular , Peso Molecular , Fragmentos de Peptídeos/isolamento & purificação , Ratos , Homologia de Sequência de Aminoácidos , TripsinaAssuntos
Galactanos/química , Glicosaminoglicanos/química , Imidoésteres/química , Ácidos Sulfúricos/química , Compostos de Trimetilsilil/química , Sequência de Carboidratos , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Dados de Sequência MolecularRESUMO
Methyl alpha- and beta-D-galactopyranosides and 4-O-beta-D-galactopyranosyl-3,6-anhydro-L-galactose dimethylacetal were sulfated with sulfuric acid and dicyclohexylcarbodiimide as a condensation reagent. The sulfated sugars were isolated by ion-exchange chromatography, characterized, and assigned by methylation analyses. On the basis of the yield of each sulfated product that was isolated, sulfation on O-6 appeared to be predominant.
Assuntos
Dicicloexilcarbodi-Imida/química , Metilgalactosídeos/química , Sulfatos/síntese química , Ácidos Sulfúricos/química , Acetais/química , Acetais/metabolismo , Sequência de Carboidratos , Carboidratos/síntese química , Carboidratos/isolamento & purificação , Cromatografia por Troca Iônica , Dissacarídeos/química , Dissacarídeos/metabolismo , Metilação , Metilgalactosídeos/metabolismo , Dados de Sequência Molecular , Estereoisomerismo , Sulfatos/isolamento & purificaçãoRESUMO
Three inhibitors (CMCTI-I, II, and III) were isolated from oriental pickling melon (Cucumis melo L. var. Conomon Makino) seeds by acetone precipitation, gel filtration, and reversed phase chromatography. The amino acid sequences of these inhibitors were: [table; see text] The reactive sites (P1 and P1' sites) of these inhibitors are presumed to be the Lys-Ile indicated by an arrow, comparing them with other squash family inhibitors. All three inhibitors can inhibit lysyl endopeptidase and trypsin at the enzyme-inhibitor ratio of 1:1.
Assuntos
Proteínas de Plantas/química , Inibidores da Tripsina/química , Sequência de Aminoácidos , Aminoácidos/análise , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Dados de Sequência Molecular , Proteínas de Plantas/isolamento & purificação , Plantas Comestíveis/química , Sementes/química , Inibidores da Tripsina/isolamento & purificaçãoRESUMO
Two almost identical trypsin isoinhibitors, LLDTI-I and LLDTI-II, from bottle gourd (Lagenaria leucantha Rusby var. Depressa Makino) seeds were purified by acetone precipitation, gel filtration and reversed phase chromatography. LLDTI-I and LLDTI-II consist of 30 and 29 amino acid residues, respectively, and have identical sequences, except that LLDTI-I has one additional pyroglutamic acid residue at N-terminus. Both proteins are strong inhibitors of bovine trypsin, with Ki values of 2.4.10(-10) M (LLDTI-I) and 9.6.10(-11) M (LLDTI-II). Amino acid sequences are as follows: [sequence: see text]
Assuntos
Plantas/química , Inibidores da Tripsina/isolamento & purificação , Sequência de Aminoácidos , Dados de Sequência Molecular , Mapeamento de Peptídeos , Sementes , Alinhamento de Sequência , Inibidores da Tripsina/químicaRESUMO
Gourd seed inhibitors were purified in the following manner: gourd seeds were ground and extracted with 10 mM ammonium carbonate, pH 7.8. The extract was precipitated with 65-90% acetone and the acetone precipitates were gel filtered in a Cellulofine GCL-90-m column. Fractions of 3000 Da showing trypsin inhibitory activity were combined and purified further by ion exchange and reversed phase chromatographies. Three inhibitors, LLTI-I, II, and III were thus purified to homogeneity and the amino acid sequences of these inhibitors were: [sequence: see text] The exact sequences are unique but very similar to proteinase inhibitors belonging to the squash family. Based on the sequence, it is assumed that the peptide bond (Arg-Ile) found in the three inhibitors is the reactive site for trypsin. The Ki values estimated for complexes of LLTI-I, II, and III with bovine trypsin were 3.6 x 10(-10) M, 6.5 x 10(-11) M, and 3.0 x 10(-11) M, respectively.
