Acute monocytic leukemia is a type of myeloid leukemia that develops in monocytes. The current clinical therapies for leukemia are unsatisfactory due to their side effects and nonspecificity toward ...target cells. Some lectins display antitumor activity and may specifically recognize cancer cells by binding to carbohydrate structures on their surface. Therefore, this study evaluated the response of the human monocytic leukemia cell lines THP‐1 to the Olneya tesota PF2 lectin. The induction of apoptosis and reactive oxygen species production in PF2‐treated cells was evaluated by flow cytometry, and the lectin‐THP‐1 cell interaction and mitochondrial membrane potential were evaluated by confocal fluorescence microscopy. PF2 genotoxicity was evaluated by DNA fragmentation analysis via gel electrophoresis. The results showed that PF2 binds to THP‐1 cells, triggers apoptosis and DNA degradation, changes the mitochondrial membrane potential, and increases reactive oxygen species levels in PF2‐treated THP‐1 cells. These results suggest the potential use of PF2 for developing alternative anticancer treatments with enhanced specificity.
Chymotrypsin was purified from jumbo squid hepatopancreas (HP) with 2.4-fold and yield 1.9%, and characterized with a molecular weight of 31 kDa, as estimated by sodium dodecyl sulfatepolyacrylamide ...gel electrophoresis (SDS-PAGE). Chymotrypsin effect over collagen extracted from the mantle, fins and arms of the jumbo squid was evaluated. The enzyme exhibited the maximum activity at pH 7 and 65°C using Suc-Ala-Ala-Pro-Phe-p-nitroanilide (SAAPNA) as a substrate and it was identified using the specific inhibitors N-tosyl-L-phenylalaninechloromethyl ketone (TPCK) and phenyl methyl sulfonyl fluoride (PMSF), showing residual activities of 6% and 0%, respectively. Furthermore, high activity was observed in the pH range of 4.0 to 8.0. Purified enzyme showed a moderate
in vitro
activity using muscle collagen as a substrate. Although further research is needed, the results suggest that the enzyme has a potential application where acidic or slightly alkaline conditions are needed.
•Trypsin was isolated and purified from viscera of Pterygoplichthys disjunctivus.•It showed high activity at pH 5.5–11.0, 25–40°C and 30% salt concentration.•Viscera from P. disjunctivus may be an ...important source of trypsin.•A biotechnological tool at low processing temperatures or high salt concentration.
Pterygoplichthys disjunctivus viscera trypsin was purified by fractionation with ammonium sulphate, gel filtration, affinity and ion exchange chromatography (DEAE-Sepharose). Trypsin molecular weight was approximately 27.5kDa according to SDS–PAGE, shown a single band in zymography. It exhibited maximal activity at pH 9.5 and 40°C, using N-benzoyl-dl-arginine-p-nitroanilide (BAPNA) as substrate. Enzyme was effectively inhibited by phenyl methyl sulphonyl fluoride (PMSF) (100%), N-α-p-tosyl-l-lysine chloromethyl ketone (TLCK) (85.4%), benzamidine (80.2%), and soybean trypsin inhibitor (75.6%) and partially inhibited by N-tosyl-l-phenylalanine chloromethyl ketone (TPCK) (10.3%), ethylendiaminetetraacetic acid (EDTA) (8.7%) and pepstatin A (1.2%). Enzyme activity was slightly affected by metal ions (Fe2+>Hg2+>Mn2+>K+>Mg2+>Li+>Cu2+). Trypsin activity decreased continuously as NaCl concentration increased (0–30%). Km and kcat values were 0.13mM and 1.46s−1, respectively. Results suggest the enzyme have a potential application where room processing temperatures (25–35°C) or high salt (30%) concentration are needed, such as in fish sauce production.
Vermiculated sailfin catfish (Pterygoplichthys disjunctivus, Weber, 1991), a member of the Loricariidae family and an invasive species of several inland waters around the world, possess an enormous ...digestive tract representing about 10% of fish weight. Thus, the aim of this study was to partially characterize proteases from their digestive tracts. Azocasein digestion of the crude extract of intestine at different pH values and temperatures revealed the presence of alkaline proteases with optimum activities at pH 9.0 and 50°C. Incubation assays of the crude extract with inhibitors such as phenyl methyl sulfonyl fluoride, N-α-p-tosyl-l-lysine chloromethyl ketone, N-tosyl-phenyalanine chloromethyl ketone, benzamidine, pepstatin A and ethylenediamine tetra-acetic acid showed that trypsin and chymotrypsin are the main alkaline proteinases present. Zymography showed that the crude extract of Pterygoplichthys disjunctivus viscera contained proteases with molecular masses ranging from 21.5 to 116 kDa. Trypsin and chymotrypsin were inhibited by the following ions in decreasing order: Hg^sup 2+^, Fe^sup 2+^, Cu^sup 2+^, Li^sup +^, Mg^sup 2+^, K^sup +^, while Mn^sup 2+^, and Ca^sup 2+^ had no effect. Activities decreased continuously as the NaCl concentration increased from 0 to 30%. These results constitute important background information for future studies and for the potential biotechnological use of the crude digestive extract from this invasive species.PUBLICATION ABSTRACT
Echinometra vanbrunti is an echinoid found in abundance in the eastern Pacific, including the Gulf of California in Mexico. The aim of this study is to document its annual reproductive cycle from ...monthly sampling. Growth, condition and gonadosomatic index (GSI) were determined from morphometric data. Additionally, sex ratio and morphology of sea urchin gonads and their gametes were analysed by histology and microscopy. The growth pattern of E. vanbrunti was allometric. The monthly variations of GSI are explained by gonad condition and the gametogenesis cycle. An annual reproductive cycle was observed with higher GSI from July-September and the highest percentage of females and males in the mature stage in the same period. Gonad histology agreed with this single gametogenic cycle per year, and gametogenesis in males and females being highly synchronized in this species. Spawning period started in July and ended in November for both sexes.
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Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Pterygoplichthys disjunctivus viscera chymotrypsin was purified by fractionation with ammonium sulfate (30-70 % saturation), gel filtration, affinity, and ion exchange chromatography. Chymotrypsin ...molecular weight was approximately 29 kDa according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), shown a single band in zymogram. Electrofocusing study suggested being an anionic enzyme (pI ≈ 3.9), exhibiting maximal activity at pH 9 and 50 °C, using Suc-Ala-Ala-Pro-Phe-p-nitroanilide (SAAPNA) as substrate. Enzyme was effectively inhibited by phenyl methyl sulfonyl fluoride (PMSF) (99 %), and N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) (94 %). Enzyme activity was affected by the following ions in decreasing order: Hg(2+), Fe(2+), Cu(2+), Li(1+), Mg(2+), K(1+), Mn(2+), while Ca(2+) had no effect. Chymotrypsin activity decreased continuously as NaCl concentration increased (from 0 to 30 %). K m and V max values were 0.72 ± 1.4 mM and 1.15 ± 0.06 μmol/min/mg of protein, respectively (SAAPNA as substrate). Results suggest the enzyme has a potential application where low processing temperatures are needed, such as in fish sauce production.
El presente estudio tuvo como objetivo establecer el tipo de relación entre la procrastinación y la adicción a las redes sociales en estudiantes universitarios de pre y post grado. Se tomó como ...muestra a un total de 402 estudiantes de Lima, con edades entre 15 y 65 años, para la presente investigación se dividieron los grupos muestrales según edad y nivel de estudios. A estos estudiantes se les aplicó la Escala de procrastinación diseñada por Iparraguirre, Cangahuala y Javier (2014), y el Cuestionaro de Adicción a las Redes Sociales propuesto por Escurra y Salas (2014). Los resultados mostraron una relación significativa, directa y positiva entre ambas variables, lo cual indica que a un mayor nivel de procrastinación se asocia una mayor adicción a redes sociales, así como se obtuvo diferencias significativas entre alumnos de pre y post grado en ambas variables, denotando que los alumnos de pregrado muestran una mayor procrastinación y adicción a redes sociales en comparación con los alumnos de post grado.
Trypsin was purified from the hepatopancreas of Dosidicus gigas by fractionation with ammonium sulfate (30-70% saturation), gel filtration, affinity and ion exchange chromatography. The molecular ...weight of the trypsin obtained was ~23.5kDa according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and, showed a single band in the zymogram. The enzyme exhibited maximal activity at pH 8.5 and 40degreesC, using BAPNA as substrate. It was effectively inhibited by phenyl methyl sulfonyl fluoride (PMSF) (98%), and Na-p-Tosyl-L-lysine chloromethyl ketone (TLCK) (99%). Enzyme activity was affected by the following ions in decreasing order: Hg.sup.2+, Fe.sup.2+, Cu.sup.2+, Li.sup.1+, Mg.sup.2+, K.sup.l+, Mn.sup.2+, Ca.sup.2+. Trypsin activity decreased continuously as NaCl concentration increased from 0 to 30%. Km and k.sub.cat values were 0.085 + or - 1.45mM and 1.76 + or - 0.12s-1, respectively. The results suggest that the purified enzyme a potential agent to be used in biotechnological processes.
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