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Bersanetti, Patrí,cia A.,Park, Ho-Yong,Bae, Kyung Sook,Son, Kwang-Hee,Shin, Dong-Ha,Hirata, Izaura Y.,Juliano, Maria A.,Carmona, Adriana K.,Juliano, Luiz Elsevier 2005 Enzyme and microbial technology Vol.37 No.6
<P><B>Abstract</B></P><P>We investigated the biochemical properties of a 51.5kDa metalloprotease (arazyme, 3.4.24.40) secreted into the culture medium by <I>Aranicola proteolyticus</I>, a symbiotic bacterium of the spider <I>Nephila clavata</I>. The enzyme was purified to apparent homogeneity by ion exchange chromatography in a Resource Q column (FPLC system). The substrate specificity requirements of purified arazyme were examined using fluorescence resonance energy transfer (FRET) peptides derived from the lead sequence Abz-KLRFSKQ-EDDnp (Abz=<I>ortho</I>-aminobenzoic acid; EDDnp=ethylenediaminedinitrophenyl). Three series of peptides were assayed to map the S<SUB>2</SUB>, S<SUB>1</SUB> and <SUB><SUP>S′</SUP>1</SUB> subsites: Abz-KXRFSKQ-EDDnp, Abz-KLXFSKQ-EDDnp and Abz-KLRXSKQ-EDDnp (X are natural amino acids). The results indicated that S<SUB>1</SUB> subsite has a broad specificity, being Gly the preferred amino acid for this subsite followed by positively charged residues (Arg and His). The S<SUB>2</SUB> and <SUB><SUP>S′</SUP>1</SUB> subsites accommodated better hydrophobic residues with aliphatic or aromatic side chains (Leu, Phe). The pH effect on hydrolysis of Abz-KLFFSKQ-EDDnp indicated that optimal hydrolysis occurred at pH 8.0 or higher. The effect of NaCl on the arazyme activity depends on the substrate, but in general the activity was reduced with this salt. The temperature did not affect the enzyme from 10 to 45°C, after which activity decreased sharply. Arazyme presented high hydrolytic activity on substance P and peptides related to bradykinin. In addition, arazyme activity was resistant to the treatment by pepsin, trypsin and chymotrypsin. In conclusion, arazyme has a broad hydrolytic profile and works in very aggressive conditions, which justify its potential use in therapeutics and biotechnological applications.</P>
Natural Products from Garcinia brasiliensis as Leishmania Protease Inhibitors
Ivan O. Pereira,Diego M. Assis,Maria A. Juliano,Rodrigo L.O.R. Cunha,Clara L. Barbieri,Luis V.S. do Sacramento,Marcos J. Marques,Marcelo H. dos Santos 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.6
The infections by protozoans of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials, which cause renal and cardiac toxicity. As part of a search for new drugs against leishmaniasis, we evaluated the in vitro Leishmania protease inhibition activity of extracts (hexanic, ethyl-acetate, and ethanolic) and fukugetin, a bioflavonoid purified from the ethyl-acetate extract of the pericarp of the fruit of Garcinia brasiliensis, a tree native to Brazilian forests. The isolated compound was characterized by using spectral analyses with nuclear magnetic resonance, mass spectroscopy, ultraviolet, and infrared techniques. The ethyl-acetate extract and the compound fukugetin showed significant activity as inhibitors of Leishmania's proteases, with mean (±SD) IC50 (50% inhibition concentration of protease activity) values of 15.0±1.3 μg/mL and 3.2±0.5 μM/mL, respectively, characterizing a bioguided assay. In addition, this isolated compound showed no activity against promastigote and amastigote forms of L. (L.) amazonensis and mammalian cells. These results suggest that fukugetin is a potent protease inhibitor of L. (L.) amazonensis and does not cause toxicity in mammalian or Leishmania cells in vitro. This study provides new perspectives on the development of novel drugs that have leishmanicidal activity obtained from natural products and that target the parasite's proteases.