|
|
|
|
|
Carvalho,K.M.; Nava,R.A.; França,M.S.F.; Medeiros,M.A.S.; Camarão,G.C.; Juliano,L.. |
A new metalloendopeptidase was purified to apparent homogeneity from a homogenate of normal human liver using successive steps of chromatography on DEAE-cellulose, hydroxyapatite and Sephacryl S-200. The purified enzyme hydrolyzed the Pro7-Phe8 bond of bradykinin and the Ser25-Tyr26 bond of atrial natriuretic peptide. No cleavage was produced in other peptide hormones such as vasopressin, oxytocin or Met- and Leu-enkephalin. This enzyme activity was inhibited by 1 mM divalent cation chelators such as EDTA, EGTA and o-phenanthroline and was insensitive to 1 µM phosphoramidon and captopril, specific inhibitors of neutral endopeptidase (EC 3.4.24.11) and angiotensin-converting enzyme (EC 3.4.15.1), respectively. With Mr 85 kDa, the enzyme exhibits optimal... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Liver metalloendopeptidase; Bradykinin; Atrial natriuretic peptide. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000100007 |
| |
|
| |
|
|
Santana,A.N.C.; Trindade-Filho,E.M.; Cunha,R.B.; Sousa,M.V.; Cavalheiro,E.A.; Carvalho,K.M.. |
In this study, the behavioral and electroencephalographic (EEG) analysis of seizures induced by the intrahippocampal injection in rats of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera, was determined. The first alterations occurred during microinjection of granulitoxin (8 µg) into the dorsal hippocampus and consisted of seizure activity that began in the hippocampus and spread rapidly to the occipital cortex. This activity lasted 20-30 s, and during this period the rats presented immobility. During the first 40-50 min after its administration, three to four other similar short EEG seizure periods occurred and the rats presented the following behavioral alterations: akinesia, facial automatisms, head tremor, salivation,... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Bunodosoma granulifera; Granulitoxin; Sea anemones; Toxic peptides; Seizure; Electroencephalographic assay. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000600016 |
| |
|
|
Santana,A.N.C.; Leite,A.B.; França,M.S.F.; França,L.; Vale,O.C.; Cunha,R.B.; Ricart,C.A.O.; Sousa,M.V.; Carvalho,K.M.. |
A neurotoxic peptide, granulitoxin (GRX), was isolated from the sea anemone Bunodosoma granulifera. The N-terminal amino acid sequence of GRX is AKTGILDSDGPTVAGNSLSGT and its molecular mass is 4958 Da by electrospray mass spectrometry. This sequence presents a partial degree of homology with other toxins from sea anemones such as Bunodosoma caissarum, Anthopleura fuscoviridis and Anemonia sulcata. However, important differences were found: the first six amino acids of the sequence are different, Arg-14 was replaced by Ala and no cysteine residues were present in the partial sequence, while two cysteine residues were present in the first 21 amino acids of other toxins described above. Purified GRX injected ip (800 µg/kg) into mice produced severe neurotoxic... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Bunodosoma granulifera; Sea anemones; Toxic peptides. |
Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998001000015 |
| |
|
|
Medeiros,M.A.S.; França,M.S.F.; Boileau,G.; Juliano,L.; Carvalho,K.M.. |
Two intramolecularly quenched fluorogenic peptides containing o-aminobenzoyl (Abz) and ethylenediamine 2,4-dinitrophenyl (EDDnp) groups at amino- and carboxyl-terminal amino acid residues, Abz-<!-- $MVD$:face("Times") -->DArg-Arg-Leu-EDDnp (Abz-<!-- $MVD$:face("Times") -->DRRL-EDDnp) and Abz-<!-- $MVD$:face("Times") -->DArg-Arg-Phe-EDDnp (Abz-<!-- $MVD$:face("Times") -->DRRF-EDDnp), were selectively hydrolyzed by neutral endopeptidase (NEP, enkephalinase, neprilysin, EC 3.4.24.11) at the Arg-Leu and Arg-Phe bonds, respectively. The kinetic parameters for the NEP-catalyzed hydrolysis of Abz-<!-- $MVD$:face("Times") -->DRRL-EDDnp and Abz-<!-- $MVD$:face("Times") -->DRRF-EDDnp were Km = 2.8 µM, kcat = 5.3 min-1, kcat/Km = 2... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Neutral endopeptidase; Enkephalinase; Neprilysin; Fluorogenic substrates; Phosphoramidon. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997001000003 |
| |
|
|
|