Crecimiento in vitro y producción de enzimas degradadoras de pared celular vegetal de aislamientos argentinos de Macrophomina phaseolina, agente causal de la podredumbre carbonosa en maíz / In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn

Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes --#91;pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase--#93; by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3 U/ml and polymethylgalacturonase between 0.15 and 1.3 U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36 U/l and 63 U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation.

Macrophomina phaseolina es un fitopatógeno polífago, causante de podredumbre carbonosa. Los daños que genera en cultivos de soja y maíz bajo siembra directa en Argentina, en períodos secos y calurosos, se incrementaron por su habilidad para sobrevivir como esclerocios en suelos y restos de cosecha. El propósito del trabajo fue estudiar la producción in vitro de enzimas degradadoras de pared celular vegetal (pectinasas --#91;poligalacturonasa y polimetilgalacturonasa--#93;; celulasas --#91;endoglucanasa--#93;; hemicelulasas --#91;endoxilanasa--#93; y la enzima ligninolítica lacasa) de varios aislamientos argentinos de M. phaseolina y evaluar la patogenicidad de esos aislamientos, como paso preliminar para establecer el papel de estas enzimas en la interacción M. phaseolina-maíz. Se estudió la cinética de crecimiento del hongo y la de la producción de dichas enzimas en medios de cultivo líquidos sintéticos con ácido glutámico como fuente de nitrógeno y con pectina, carboximetilcelulosa (CMC) o xilano como fuentes de carbono. Las pectinasas fueron las primeras enzimas detectadas y los máximos títulos registrados (1,4 UE/ml --#91;poligalacturonasa--#93; y 1,2 UE/ml --#91;polimetilgalacturonasa--#93;, respectivamente) superaron a los de celulasas y xilanasas, que aparecieron más tardíamente y en menor magnitud. Esta secuencia promovería la maceración inicial del tejido, seguida luego por la degradación de la pared celular vegetal. Se detectó actividad lacasa en todos los aislamientos (36 a 63 U/l). La agresividad de todos los aislamientos resultó alta en los 3 hospedantes evaluados: semillas de maíz, de girasol y de melón. En este trabajo se investiga por primera vez el potencial de distintos aislamientos de M. phaseolina para producir enzimas degradadoras de pared celular vegetal en cultivo líquido.

In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn.

Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes [pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase] by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3U/ml and polymethylgalacturonase between 0.15 and 1.3U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36U/l and 63U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation.

CDH1/E-cadherin and solid tumors. An updated gene-disease association analysis using bioinformatics tools.

Cancer is a group of diseases that causes millions of deaths worldwide. Among cancers, Solid Tumors (ST) stand-out due to their high incidence and mortality rates. Disruption of cell-cell adhesion is highly relevant during tumor progression. Epithelial-cadherin (protein: E-cadherin, gene: CDH1) is a key molecule in cell-cell adhesion and an abnormal expression or/and function(s) contributes to tumor progression and is altered in ST. A systematic study was carried out to gather and summarize current knowledge on CDH1/E-cadherin and ST using bioinformatics resources. The DisGeNET database was exploited to survey CDH1-associated diseases. Reported mutations in specific ST were obtained by interrogating COSMIC and IntOGen tools. CDH1 Single Nucleotide Polymorphisms (SNP) were retrieved from the dbSNP database. DisGeNET analysis identified 609 genes annotated to ST, among which CDH1 was listed. Using CDH1 as query term, 26 disease concepts were found, 21 of which were neoplasms-related terms. Using DisGeNET ALL Databases, 172 disease concepts were identified. Of those, 80 ST disease-related terms were subjected to manual curation and 75/80 (93.75%) associations were validated. On selected ST, 489 CDH1 somatic mutations were listed in COSMIC and IntOGen databases. Breast neoplasms had the highest CDH1-mutation rate. CDH1 was positioned among the 20 genes with highest mutation frequency and was confirmed as driver gene in breast cancer. Over 14,000 SNP for CDH1 were found in the dbSNP database. This report used DisGeNET to gather/compile current knowledge on gene-disease association for CDH1/E-cadherin and ST; data curation expanded the number of terms that relate them. An updated list of CDH1 somatic mutations was obtained with COSMIC and IntOGen databases and of SNP from dbSNP. This information can be used to further understand the role of CDH1/E-cadherin in health and disease.