| Registro completo |
| Provedor de dados: |
Braz. J. Plant Physiol.
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| País: |
Brazil
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| Título: |
Purification and structural stability of a trypsin inhibitor from Amazon Inga cylindrica [Vell.] Mart. seeds
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| Autores: |
Calderon,Leonardo A
Almeida Filho,Humberto A
Teles,Rozeni C. L
Medrano,Francisco J
Bloch Jr,Carlos
Santoro,Marcelo M
Freitas,Sonia M
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| Data: |
2010-01-01
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| Ano: |
2010
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| Palavras-chave: |
Inga cylindrica [Vell.] Mart
Leguminosae
Mimosoideae
Protease inhibitor
Protein stability
Trypsin inhibitor
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| Resumo: |
Inga cylindrica Trypsin Inhibitor (ICTI) was purified as a single polypeptide chain by one step anion-exchange chromatography from a crude extract of Inga cylindrica (Vell.) Mart. seeds. ICTI is a 19.5 kDa protein presenting a remarkable inhibitory activity against bovine trypsin (EC 3.4.21.4) (Ki = 4.3 nM). Circular dichroism analysis revealed that this inhibitor is a β type protein (40.4% of β-strand; 24.6% of β-turn and 6.7% of α-helix) in accordance with properties displayed in Kunitz type inhibitors. ICTI is a thermal stable protein within a wide range of pH (1.6 to 10.0) exhibiting highest stability at pH 7.0 as indicated by Tm of 70.0 ºC and ΔG25 of 48.5 ± 0.7 kJ.mol-1. The values of ΔG25 at pH 1.6 (22.5 ± 1.2 kJ.mol-1) and pH 10.0 (31.5 ± 1.0 kJ.mol-1) indicate a reduced structural stability of the protein under these conditions. This is likely to result from pKa differences of the acid and basic side chains reflecting the changes in the non-covalent interactions in the folded state.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000200001
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| Editor: |
Brazilian Journal of Plant Physiology
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| Relação: |
10.1590/S1677-04202010000200001
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| Formato: |
text/html
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| Fonte: |
Brazilian Journal of Plant Physiology v.22 n.2 2010
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| Direitos: |
info:eu-repo/semantics/openAccess
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