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1.
Sci Rep ; 6: 20051, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26837852

RESUMEN

Cervical cancer is one of the most common cancers among women worldwide. Current standards of care for cervical cancer includes surgery, radiation, and chemotherapy. Conventional chemotherapy fails to elicit therapeutic responses and causes severe systemic toxicity. Thus, developing a natural product based, safe treatment modality would be a highly viable option. Curcumin (CUR) is a well-known natural compound, which exhibits excellent anti-cancer potential by regulating many proliferative, oncogenic, and chemo-resistance associated genes/proteins. However, due to rapid degradation and poor bioavailability, its translational and clinical use has been limited. To improve these clinically relevant parameters, we report a poly(lactic-co-glycolic acid) based curcumin nanoparticle formulation (Nano-CUR). This study demonstrates that in comparison to free CUR, Nano-CUR effectively inhibits cell growth, induces apoptosis, and arrests the cell cycle in cervical cancer cell lines. Nano-CUR treatment modulated entities such as miRNAs, transcription factors, and proteins associated with carcinogenesis. Moreover, Nano-CUR effectively reduced the tumor burden in a pre-clinical orthotopic mouse model of cervical cancer by decreasing oncogenic miRNA-21, suppressing nuclear ß-catenin, and abrogating expression of E6/E7 HPV oncoproteins including smoking compound benzo[a]pyrene (BaP) induced E6/E7 and IL-6 expression. These superior pre-clinical data suggest that Nano-CUR may be an effective therapeutic modality for cervical cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Curcumina/administración & dosificación , Ácido Láctico/química , Ácido Poliglicólico/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Curcumina/química , Curcumina/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ácido Láctico/administración & dosificación , Ratones , MicroARNs/genética , Nanopartículas/administración & dosificación , Nanopartículas/química , Ácido Poliglicólico/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Neoplasias del Cuello Uterino/genética , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Oncotarget ; 5(17): 7599-609, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25277192

RESUMEN

Pancreatic cancer has a poor prognosis due to late diagnosis and ineffective therapeutic multimodality. MUC13, a transmembrane mucin is highly involved in pancreatic cancer progression. Thus, understanding its regulatory molecular mechanisms may offer new avenue of therapy for prevention/treatment of pancreatic cancer. Herein, we report a novel microRNA (miR-145)-mediated mechanism regulating aberrant MUC13 expression in pancreatic cancer. We report that miR-145 expression inversely correlates with MUC13 expression in pancreatic cancer cells and human tumor tissues. miR-145 is predominantly present in normal pancreatic tissues and early Pancreatic Ductal Adenocarcinoma (PDAC) precursor lesions (PanIN I) and is progressively suppressed over the course of development from PanIN II/III to late stage poorly differentiated PDAC. We demonstrate that miR-145 targets 3' untranslated region of MUC13 and thus downregulates MUC13 protein expression in cells. Interestingly, transfection of miR-145 inhibits cell proliferation, invasion and enhances gemcitabine sensitivity. It causes reduction of HER2, P-AKT, PAK1 and an increase in p53. Similar results were found when MUC13 was specifically inhibited by shRNA directed at MUC13. Additionally, intratumoral injections of miR-145 in xenograft mice inhibited tumor growth via suppression of MUC13 and its downstream target, HER2. These results suggest miR-145 as a novel regulator of MUC13 in pancreatic cancer.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , Mucinas/biosíntesis , Neoplasias Pancreáticas/genética , Animales , Western Blotting , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Técnica del Anticuerpo Fluorescente , Xenoinjertos , Humanos , Inmunohistoquímica , Hibridación in Situ , Ratones , Ratones Desnudos , Microscopía Confocal , Mucinas/genética , Invasividad Neoplásica/genética , Neoplasias Pancreáticas/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
3.
Mol Cancer Ther ; 12(6): 1049-59, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23580416

RESUMEN

Prostate cancer is one of the most prevalent cancers in males and ranks as the second most common cause of cancer-related deaths. 2-methoxyestradiol (2-ME), an endogenous estrogen metabolite, is a promising anticancer agent for various types of cancers. Although 2-ME has been shown to activate c-Jun-NH2-kinase (JNK) and mitochondrial-dependent apoptotic signaling pathways, the underlying mechanisms, including downstream effectors, remain unclear. Here, we report that the human Bcl-2 homology 3 (BH3)-only protein harakiri (Hrk) is a critical effector of 2-ME-induced JNK/mitochondria-dependent apoptosis in prostate cancer cells. Hrk mRNA and protein are preferentially upregulated by 2-ME, and Hrk induction is dependent on the JNK activation of c-Jun. Hrk knockdown prevents 2-ME-mediated apoptosis by attenuating the decrease in mitochondrial membrane potential, subsequent cytochrome c (cyt c) release, and caspase activation. Involvement of the proapoptotic protein Bak in this process suggested the possible interaction between Hrk and Bak. Thus, Hrk activation by 2-ME or its overexpression displaced Bak from the complex with antiapoptotic protein Bcl-xL, whereas deletion of the Hrk BH3 domain abolished its interaction with Bcl-xL, reducing the proapoptotic function of Hrk. Finally, Hrk is also involved in the 2-ME-mediated reduction of X-linked inhibitor of apoptosis through Bak activation in prostate cancer cells. Together, our findings suggest that induction of the BH3-only protein Hrk is a critical step in 2-ME activation of the JNK-induced apoptotic pathway, targeting mitochondria by liberating proapoptotic protein Bak.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Apoptosis/genética , Neoplasias de la Próstata/metabolismo , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo , 2-Metoxiestradiol , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular Tumoral , Estradiol/análogos & derivados , Estradiol/farmacología , Estrógenos/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , MAP Quinasa Quinasa 4/metabolismo , Masculino , Mitocondrias/metabolismo , Mitocondrias/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Transducción de Señal/efectos de los fármacos , Proteína Destructora del Antagonista Homólogo bcl-2/biosíntesis
4.
Carcinogenesis ; 33(2): 420-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22159223

RESUMEN

Long-term exposure to estrogen and its metabolites may play an important role in renal cell carcinogenesis. Catechol-O-methyltransferase (COMT) participates in the estrogen metabolism pathway by neutralizing toxic substances. Although reduced COMT activity has been suggested to be a risk factor for estrogen-associated cancers, no studies have investigated the biological significance of COMT in the pathogenesis of human renal cell cancers (RCCs). We initially found that COMT levels are significantly decreased in human RCC tissues and cells suggesting it plays a suppressive role in tumor development. However, transient overexpression of COMT has no functional effect on RCC cell lines. In contrast, when cells overexpressing COMT are treated with its substrate 4-hydroxyestradiol (4-OHE(2)), growth is inhibited by apoptotic cell death. We also found that COMT overexpression combined with 4-OHE(2) induces upregulation of growth arrest- and DNA damage-inducible protein α (GADD45α). We further show that downregulation of GADD45α by a small interfering RNA-mediated approach inhibits cell death, indicating the essential role of GADD45α in the underlying mechanism of COMT action in response to 4-OHE(2). Finally, 4-methoxyestradiol fully reproduces the antiproliferative function of COMT with 4-OHE(2) by promoting GADD45α induction. Together, these findings show that COMT in the presence of 4-OHE(2) prevents RCC cell proliferation by enhancing apoptosis and that GADD45α plays a critical role in the COMT-mediated inhibition of RCC.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/enzimología , Catecol O-Metiltransferasa/metabolismo , Estradiol/análogos & derivados , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/enzimología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Catecol O-Metiltransferasa/biosíntesis , Catecol O-Metiltransferasa/genética , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Muerte Celular/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Estradiol/metabolismo , Estradiol/farmacología , Estrógenos de Catecol , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , ARN Mensajero/genética , Regulación hacia Arriba/efectos de los fármacos
5.
Cancer ; 117(8): 1649-60, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21472712

RESUMEN

BACKGROUND: To the authors' knowledge, the functional significance of the Wnt antagonist dickkopf homolog 4 (DKK4) has not been investigated previously in renal cancer. METHODS: The authors initially observed that the expression of DKK4 was significantly higher in renal cancer tissues compared with adjacent normal kidney tissues. To assess the function of DKK4, stable DKK4-transfected cells were established, and functional analyses were performed, including a T-cell factor/lymphoid enhancer factor (TCF/LEF) reporter assay and tests for cell viability, colony formation, apoptosis, cell cycle, invasive capability, wound-healing capability, and in vivo tumor growth. RESULTS: The relative TCF/LEF activity was significantly lower in DKK4-transfected cells compared with empty vector, and nuclear ß-catenin expression was decreased in DKK4 transfectants. In addition, expression levels of the ß-catenin downstream effector proteins cyclin D1 and c-Myc were decreased in DKK4 transfectants. However, greater invasiveness and migration were observed in stably transfected DKK4 cells. Increased growth of DKK4-transfected tumors also was observed in nude mice. Members of the Wnt noncanonical/c-Jun-NH2 kinase (JNK) signaling pathway also were effected, such as c-Jun, which had significantly increased expression and phosphorylation in DKK4-stable transfectants, and matrix metalloproteinase-2, which had significantly increased expression in DKK4-stable transfectants. CONCLUSIONS: This is the first study to indicate that DKK4 expression is increased in renal cancer tissues and that DKK4 activates the noncanonical JNK signaling pathway while inhibiting the Wnt-canonical pathway.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neoplasias Renales/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Wnt/metabolismo , Adulto , Anciano , Línea Celular Tumoral , Células Clonales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
6.
Mol Carcinog ; 50(6): 449-57, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21268126

RESUMEN

The Wnt signaling pathway is activated in most cancers while Wnt antagonist genes are inactivated. However, the functional significance and mechanisms of inactivation of Wnt antagonist Dkk-3 gene in renal cell carcinoma (RCC) has not been reported. In this study, we examined potential epigenetic mechanisms regulating Dkk-3 expression in RCC cells and whether Dkk-3 expression affects cell growth and apoptosis. The expression of Dkk-3 is regulated by histone modification rather than CpG island DNA methylation in renal cancer cells. Renal cancer cell proliferation was significantly inhibited and apoptosis was promoted in Dkk-3 transfected renal cancer cells. Dkk-3 did not inhibit the Wnt/beta-catenin signaling pathway but induced apoptosis via the noncanonical JNK pathway in renal cancer cells. Expression of p21, MDM-2, and Puma genes were increased after transfecting RCC cell lines with a Dkk-3 expression plasmid. Overexpression of Dkk-3 induced G(0)/G(1) arrest together with an increase in p21 expression. Growth of stable Dkk-3 transfected cells in nude mice was decreased compared to controls. Our data show for the first time that mRNA expression of Dkk-3 is regulated by histone modification and that Dkk-3 inhibits renal cancer growth through modulation of cell cycle and apoptotic pathways.


Asunto(s)
Apoptosis , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Renales/metabolismo , Proteínas Wnt/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Western Blotting , Carcinoma de Células Renales/genética , Ciclo Celular , Proliferación Celular , Células Cultivadas , Quimiocinas , Inmunoprecipitación de Cromatina , Islas de CpG , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Metilación de ADN , Epigénesis Genética , Histonas/metabolismo , Humanos , Técnicas para Inmunoenzimas , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/genética , Luciferasas/metabolismo , Ratones , Ratones Desnudos , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
7.
Int J Cancer ; 128(8): 1793-803, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20549706

RESUMEN

The functional significance of Wnt antagonist DKK1 has not been investigated in renal cell carcinoma (RCC). Therefore, we hypothesized that DKK1 may be a tumor suppressor gene and is epigenetically silenced, thus decreased DKK1 may cause progression of RCC. To assess the function of DKK1, we established stable DKK1 transfected cells and monitored them regarding cell viability, colony formation, apoptosis, cell cycle, and invasive capability. RCC cell lines had decreased levels of DKK1, which were increased after treatment with 5-Aza-2'-deoxycytidine and trichostatin A. In chromatin immunoprecipitation assay, the level of dimethyl H3K9 and trimethyl H3K27 was decreased after 5-Aza-2'-deoxycytidine/trichostatin A treatment in RCC cell lines. Increased methylation was also associated with higher pathological stages in primary RCC tissues. T-cell factor/lymphoid enhancer factor activity and nuclear beta-catenin expression were not changed in DKK1 transfectants. Also the expression of cyclinD1 and c-Myc was not changed in DKK1 transfectants. These results suggest that DKK1 may not be involved in the beta-catenin dependent pathway. We also evaluated the expression of various related genes. Cleaved caspase3, p53, p21 and puma expression were significantly upregulated in the DKK1 transfected cells. The population of apoptotic cells was increased in stable DKK1 cells and tumor growth suppression was also observed in nude mice with DKK1 transfected cells. In conclusion, this is the first report to show that DKK1 expression is epigenetically silenced in kidney cancer and its reexpression induces apoptosis and cell cycle arrest in RCC.


Asunto(s)
Apoptosis , Carcinoma de Células Renales/patología , Proliferación Celular , Genes Supresores de Tumor , Péptidos y Proteínas de Señalización Intercelular/fisiología , Neoplasias Renales/patología , Proteínas Wnt/antagonistas & inhibidores , Antimetabolitos Antineoplásicos/farmacología , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacología , Western Blotting , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Inmunoprecipitación de Cromatina , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Metilación de ADN , Decitabina , Epigénesis Genética , Femenino , Humanos , Ácidos Hidroxámicos/farmacología , Técnicas para Inmunoenzimas , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Masculino , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
8.
Carcinogenesis ; 31(9): 1620-6, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20554747

RESUMEN

Endometrial cancer (EC) is a steroid hormone-dependent cancer. Uridine 5'-diphospho-glucuronosyltransferase enzymes conjugate and detoxify endogenous and exogenous steroid hormones and environmental carcinogens. Among these enzymes, the function of UGT2B17 is unknown except for glucuronidation. The messenger RNA expression of UGT2B17 and myeloid cell leukemia-1 (Mcl-1) was significantly increased in EC tissues compared with matched normal endometrial tissues. Therefore, we focused on the function of UGT2B17 in EC. A total of nine patients with confirmed EC were enrolled in this study to investigate the expression of UGT2B17 and target genes. EC cell lines were used for functional tests including cell growth, invasion, apoptosis and cell cycle analyses. To find the target genes of UGT2B17, we performed microarray analysis to see which genes were upregulated or downregulated by UGT2B17-transfected cells. Functional analysis showed decreased numbers of viable cells and increased numbers of apoptotic cells in si-UGT2B17-transfected Ishikawa cells. Among microarray target genes, Mcl-1 was significantly downregulated in si-UGT2B17-transfected cells. We also found upregulation of Puma protein, a target of Mcl-1, in si-UGT2B17-transfected cells. This is the first report to show that UGT2B17 and Mcl-1 expression are upregulated in EC tissues and that UGT2B17 depletion induces inhibition of cell growth and apoptosis in EC cells through Mcl-1 downregulation.


Asunto(s)
Adenocarcinoma/enzimología , Neoplasias Endometriales/enzimología , Regulación Enzimológica de la Expresión Génica , Glucuronosiltransferasa/fisiología , Adenocarcinoma/patología , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Estudios de Casos y Controles , Adhesión Celular , Ciclo Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Neoplasias Endometriales/patología , Femenino , Perfilación de la Expresión Génica , Genotipo , Humanos , Antígenos de Histocompatibilidad Menor , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Mensajero/genética , ARN Interferente Pequeño/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Biochem Biophys Res Commun ; 383(4): 440-4, 2009 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-19364498

RESUMEN

Mismatch repair is one of several DNA repair pathways of which defects may lead to cancer. We hypothesize that polymorphisms of the MLH1 gene can be a risk factor for benign prostatic hyperplasia (BPH) and prostate cancer. The genetic distribution of MLH1 polymorphisms that lead to amino acid changes at codons 132, 219, 384, and 723 were analyzed in BPH and sporadic prostate cancer patients, and compared to healthy controls from an Asian population. These experiments demonstrate a protective role for the codon 384 variant allele against prostate cancer (P=0.031) but not BPH when compared to normal controls and furthermore, an inverse association was observed with stage (P=0.074) and grade (P=0.056) of cancer. This is the first report that demonstrates a protective effect for the race-related MLH1 polymorphism at codon 384 against prostate cancer and these results are important in understanding their role in this disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Predisposición Genética a la Enfermedad , Proteínas Nucleares/genética , Hiperplasia Prostática/genética , Neoplasias de la Próstata/genética , Anciano , Sustitución de Aminoácidos , Humanos , Masculino , Homólogo 1 de la Proteína MutL , Polimorfismo Genético
10.
Arch Microbiol ; 191(3): 241-53, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19050850

RESUMEN

The propensity of bacterium to sporulate or retain the vegetative form depends on the amount of phosphorylated Spo0A (Spo0A(-P)), regulated by Spo0E multigene family of phosphatases (Spo0E, YisI and YnzD). Phylogenetic analysis revealed that Spo0E multigene family of phosphatases (SMFP) descends in two distinct clades of aerobic (Bacillus cluster) and anaerobic (Clostridia cluster) sporulating bacteria. High sequence conservation within species gives a notion that these members could have evolved through lineage and species-specific duplication event. Of the five genes in Bacillus cereus group, three are pathogen specific, and their synteny suggests that these paralogs could be involved in the regulation of amino acid metabolism and its transport. Overexpression of B. subtilis Spo0E, an ortholog of SMFP members in B. anthracis (BAS1251), resulted in sporulation deficient phenotype in B. anthracis. B. anthracis Spo0A(-P) binds to a consensus DNA sequence 5'-TGNCGAA-3' ('0A-like box') and loses its DNA binding ability following treatment with B. subtilis Spo0E. Thus, B. subtilis Spo0E acts on B. anthracis Spo0A(-P) and, therefore could complement the function of BAS1251. Further, since '0A-like box' are present in the promoter region of abrB gene, a known regulator of anthrax toxin gene expression, cross talk among SMFP members and Spo0A(-P)-AbrB could regulate the expression of anthrax toxin genes.


Asunto(s)
Bacillus anthracis/genética , Proteínas Bacterianas/genética , Evolución Molecular , Familia de Multigenes , Bacillus anthracis/enzimología , Secuencia Conservada , ADN Bacteriano/metabolismo , Proteínas de Unión al ADN/genética , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Monoéster Fosfórico Hidrolasas/genética , Filogenia , Alineación de Secuencia , Especificidad de la Especie
11.
Arch Microbiol ; 189(1): 71-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17713759

RESUMEN

Bacillus anthracis makes highly stable, heat-resistant spores which remain viable for decades. Effect of various stress conditions on sporulation in B. anthracis was studied in nutrient-deprived and sporulation medium adjusted to various pH and temperatures. The results revealed that sporulation efficiency was dependent on conditions prevailing during sporulation. Sporulation occurred earlier in culture sporulating at alkaline pH or in PBS than control. Spores formed in PBS were highly sensitive towards spore denaturants whereas, those formed at 45 degrees C were highly resistant. The decimal reduction time (D-10 time) of the spores formed at 45 degrees C by wet heat, 2 M HCl, 2 M NaOH and 2 M H(2)O(2) was higher than the respective D-10 time for the spores formed in PBS. The dipicolinic acid (DPA) content and germination efficiency was highest in spores formed at 45 degrees C. Since DPA is related to spore sensitivity towards heat and chemicals, the increased DPA content of spores prepared at 45 degrees C may be responsible for increased resistance to wet heat and other denaturants. The size of spores formed at 45 degrees C was smallest amongst all. The study reveals that temperature, pH and nutrient availability during sporulation affect properties of B. anthracis spores.


Asunto(s)
Bacillus anthracis/química , Bacillus anthracis/fisiología , Bacillus anthracis/efectos de los fármacos , Bacillus anthracis/efectos de la radiación , Proteínas Bacterianas/metabolismo , Tamaño de la Célula , Electroforesis en Gel Bidimensional , Ácido Clorhídrico/farmacología , Peróxido de Hidrógeno/farmacología , Concentración de Iones de Hidrógeno , Hidróxido de Sodio/farmacología , Esporas Bacterianas/química , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/fisiología , Esporas Bacterianas/efectos de la radiación , Temperatura , Rayos Ultravioleta
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