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1.
Int J Mol Cell Med ; 12(1): 1-17, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37942260

RESUMEN

Leukemia is a type of cancer that affects the blood and bone marrow. Acute lymphoid leukaemia, also known as ALL, is regarded as one of the deadliest forms of cancer. Due to the rapid increase in various cancer cases and the development of resistance in cancer cells, it is necessary to identify novel lead molecules with more potent anticancer properties. There is a growing interest in using herbal products/analogs as multi-component agents (as anticancer agents and immunomodulators) for cancer treatment. In the present investigation, an attempt has been made to explore the anticancer and immunomodulatory activity of P19, an analog of parthenin in ALL. P19 was reported to exhibit anticancer efficacy by triggering apoptotic signaling events in human leukaemia HL-60 cells by significant NO production. In contrast to this finding, ROS and NO were not required for P19-mediated apoptosis in Raji cells. The mechanism of action of P19 was observed to be cancer cell lineage dependent. P19 demonstrated very effective anticancer properties against ALL (IC50 3µM). Molecular investigations revealed that P19 induced mitochondrion mediated apoptosis by Bax localization to mitochondria and enhanced cytosolic calcium in the cytoplasm. Further activation of the caspase 3, caspase 8 and PARP cleavage suggested the involvement of the caspase-mediated apoptosis. Anti-proliferative activity revealed the telomerase inhibition and cell cycle arrest in G0/G1 phase after P19 treatment. Immunomodulatory effects of the P19 revealed the enhanced INFÉ£ and NO production in Jurkat and THP cells. Owing to its antiproliferative and immunomodulatory potential against leukemia cells P19 can further be explored as effective therapeutics against leukemia.

2.
Biotechnol Appl Biochem ; 63(5): 669-678, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26224294

RESUMEN

A thermotolerant bacterium Paenibacillus thiaminolyticus with an ability to produce extracellular ß-mannanase was isolated from a soil sample. Bacterium produced 45 U/mL ß-mannanase at 50 °C. The culture conditions for high-level production of ß-mannanase were optimized. Optimized MS medium [wheat bran 2% (w/v), ammonium sulfate 0.3% (w/v), yeast extract, and peptone (0.025% each) pH 6.5] was inoculated with 2% of 16 H old culture.  The culture was incubated at 50 °C for 48 H resulting in 24-folds higher ß-mannanase production (1,100 ± 50 U/mL). Optimum pH and temperature for enzyme activity of the crude enzyme was 6.0 and 60 °C, respectively. The enzyme demonstrated 65% relative enzyme activity at 37 °C. The hydrolytic activity of the crude enzymatic preparation was assessed on various agro residues. Thin-layer chromatographic analysis showed that the enzyme activity to saccharify heteromannans resulted in production of a mixture of manno-oligosaccharides (MOS) and enzyme exhibited classic endo-activity. To evaluate the possible prebiotic potential of the MOS thus obtained, initial screening for their ability to support the growth of probiotics was carried out by the pure culture method. Bifidobacterium and Lactobacillus sp. responded positively to the addition of enzymatically derived oligosaccharides and their numbers increased significantly.


Asunto(s)
Biotecnología/métodos , Paenibacillus/metabolismo , Prebióticos , beta-Manosidasa/biosíntesis , beta-Manosidasa/metabolismo , Fermentación , Inmersión , Manosa/química , Oligosacáridos/química , Oligosacáridos/metabolismo , beta-Manosidasa/aislamiento & purificación
3.
Mol Biol Rep ; 39(8): 8353-61, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22711301

RESUMEN

The gene encoding a thermostable pectinase was isolated from a soil metagenome sample. The gene sequence corresponded to an open reading frame of 1,311 bp encoding a translation product of 47.9 kDa. It showed maximum (93 %) identity to a Bacillus licheniformis glycoside hydrolase. Deduced amino acid analysis showed an absence of highly conserved cysteine residues in the N-terminal region at positions 24 and 42, and in the C-terminal region at positions 389, 394, 413 and 424. pQpecJKR01 (pQE30 expression vector containing the pectinase gene) was expressed in Escherichia coli strain M15 as a recombinant fusion protein containing an N-terminal 6× His tag. Biochemical properties of this pectinase were novel. The enzyme had temperature and pH optima of 70 °C and 7.0, respectively, but was active over a broad temperature and pH range. The enzyme was stable at 60 °C with a half-life of 5 h and the enzyme activity was inhibited by 0.1 % diethyl pyrocarbonate and 5 mM dicyclohexyl carbodiimide. The enzyme could be of great use in industrial processes due to its activity over a broad pH range and at high temperature.


Asunto(s)
Bacillus/enzimología , Bacillus/genética , Metagenoma , Poligalacturonasa/genética , Poligalacturonasa/metabolismo , Secuencia de Aminoácidos , Clonación Molecular , Activación Enzimática , Estabilidad de Enzimas , Expresión Génica , Calor , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
4.
Crit Rev Biotechnol ; 27(4): 197-216, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18085462

RESUMEN

Microbial mannanases have become biotechnologically important since they target the hydrolysis of complex polysaccharides of plant tissues into simple molecules like manno-oligosaccharides and mannoses. The role of mannanases in the paper and pulp industry is well established and recently they have found application in the food and feed technology, coffee extraction, oil drilling and detergent industry. Mannanses are enzymes produced mainly from microorganisms but mannanases produced from plants and animals have also been reported. Bacterial mannanases are mostly extracellular and can act in a wide range of pH and temperature, though acidic and neutral mannanases are more common. This review will focus on complex mannan structure and the microbial enzyme complex involved in its complete breakdown, mannanase sources, production conditions and their applications in the commercial sector. The reference to plant and animal mannanases has been made to complete the overview. However, the major emphasis of the review is on the microbial mannanases.


Asunto(s)
Bacterias/enzimología , Proteínas Bacterianas/biosíntesis , Biotecnología/métodos , Manosidasas/química , Manosidasas/metabolismo , Bacterias/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Concentración de Iones de Hidrógeno , Hidrólisis , Mananos/química , Mananos/metabolismo , Manosidasas/genética , Estructura Molecular , Peso Molecular , Especificidad por Sustrato , Temperatura
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