{"id":135838,"date":"2010-04-27T13:24:38","date_gmt":"2010-04-27T12:24:38","guid":{"rendered":"http:\/\/www.madrimasd.org\/blogs\/universo\/?p=135838"},"modified":"2010-04-28T14:45:01","modified_gmt":"2010-04-28T13:45:01","slug":"la-extraordinaria-genetica-de-los-microorganismos-del-suelo","status":"publish","type":"post","link":"https:\/\/www.madrimasd.org\/blogs\/universo\/2010\/04\/27\/135838","title":{"rendered":"La Extraordinaria Gen\u00e9tica de los Microorganismos del Suelo"},"content":{"rendered":"

Como la mayor\u00eda de vosotros sab\u00e9is, los organismos del suelo que atesoran una mayor biodiversidad<\/span><\/strong> resultan ser las bacterias y<\/span><\/strong> los hongos<\/a>. Si bien se sab\u00eda que el flujo horizontal de genes<\/strong><\/span> entre las bacterias era muy frecuente, no se sospechaba lo mismo en el universo f\u00fangico<\/strong><\/span>, ya que se pensaba que este mecanismo era ocasional en relaci\u00f3n a la herencia vertical. Nuevo varapalo para los untraneodarwinistas. \u00a1Qu\u00e9 la vamos a hacer! Ahora resulta, que habr\u00eda que reanalizar cuales son los mecanismos gen\u00e9ticos dominantes en las comunidades del suelo<\/span><\/strong>, ya que la noticia que el 24\/3\/2010 ofreci\u00f3 Terradaily<\/span><\/strong>, cuestiona las preconcepciones previas. Tal descubrimiento posee un gran inter\u00e9s, fitosanitario, econ\u00f3mico y de salud p\u00fablica<\/span><\/strong>, por cuanto las infecciones de los hongos del suelo en los cultivos generan miles de millones de p\u00e9rdidas anuales, a la par que causan serias enfermedades al\u00a0ser humano.<\/p>\n

\u00a0\"fusarium_verticillioides-fuente-wikipedia\"<\/p>\n

Fussariun el hongo estudiado en esta investigaci\u00f3n. Fuente: Wikipedia<\/a><\/p>\n

<\/p>\n

No se tata, ni mucho menos de un descubrimiento m\u00e1s, ni desde el punto de vista de la ciencia b\u00e1sica ni aplicada. Al parecer, el mecanismo que genera el flujo horizontal de genes en bacterias y hongos es muy distinto<\/span><\/strong>, como es l\u00f3gico, por cuanto hablamos de procariotas y eucariotas, respectivamente. En el \u00faltimo caso se acaba de demostrar la transferencia horizontal de \u00bfcromosamas, genes? completos entre organismos distintos<\/span><\/strong> (ver g\u00e9nero Fusarium<\/a>). Sea como sea, tanto las unas como los otros pueden adquirir mucho m\u00e1s r\u00e1pidamente resistencia a los antibi\u00f3ticos y fungicidas que mediante la herencia vertical<\/span><\/strong>. Los hongos se encuentran mucho m\u00e1s emparentados con los seres humanos que las bacterias, lo cual deviene en una seria preocupaci\u00f3n para los expertos en salud p\u00fablica. Recordemos que varios tipos de hongos pueden causar enfermedades, simult\u00e1neamente, en los seres humanos, ganado y plantas<\/span><\/strong>. Si bien las \u00faltimas son menos frecuentes, tambi\u00e9n son dif\u00edciles de tratar, afectando gravemente la salud de personas inmuno-deprimidas<\/span><\/strong>, como las que padecen SIDA<\/span><\/strong>. No viene de m\u00e1s recordar que muchas enfermedades intraospitalarias o nosocomiales<\/span><\/strong> tienen su origen en especies que habitaban en el suelo, si es que ya podemos utilizar tal concepto con rigor en el mundo f\u00fangico, como tambi\u00e9n ocurri\u00f3 con anterioridad en el bacteriano.<\/p>\n

Tal hallazgo ayudar\u00e1 a entender mejor la rapidez con que se propaga la resistencia a los f\u00e1rmacos f\u00fangicos y fungicidas de los cultivos<\/span><\/strong>. Esperemos tambi\u00e9n que sea \u00fatil con vistas a que los pol\u00edticos y colegas de otras disciplinas entiendan la vital importancia de ese universo invisible que tenemos bajo nuestros pies. As\u00ed, por ejemplo, ya nadie puede acusar de ret\u00f3rica la cuesti\u00f3n previamente planteada: \u00bfqu\u00e9 tipo de herencia gen\u00e9tica domina en los suelos, la vertical <\/strong><\/span>(como defienden los ultra-neodarvinistas) o la horizontal? <\/strong><\/span>Una vez m\u00e1s, reiteremos que se trata de taxa enormemente diversos, mucho m\u00e1s que los de gran tama\u00f1o<\/span><\/strong>.<\/p>\n

Toda la sociedad debe ser consciente, que tirar la basura, utilizar plaguicidas en cantidades agro-industriales, e incluso esa detestable costumbre de escupir al suelo nuestras mucosidades, devienen en bombas de relojer\u00eda (entre otras pr\u00e1cticas \u201csustentables\u201d).<\/p>\n

Apostamos cada vez m\u00e1s por sustituir una revoluci\u00f3n verde biotecnol\u00f3gica por otra agroecol\u00f3gica<\/strong> <\/span>que devuelva la armon\u00eda a las comunidades ed\u00e1ficas, en lugar de inestabilizarla a base de venenos o tocando los genes a sus moradores, sin ton ni son, ya que la primera fomenta el mecanismo mostrado, a la par que\u00a0ha generado una pandemia contaminante de dimensiones globales.<\/p>\n

\u00a0<\/p>\n

Los autores terminan pregunt\u00e1ndose si habr\u00eda que cambiar el concepto de \u00e1rbol de la vida por el de red de la vida, dado que el flujo horizontal de genes comienza a mostrarse como un mecanismo determinante de la evoluci\u00f3n, justamente en los taxa m\u00e1s biodiversos<\/strong><\/span><\/p>\n

El ser humano parece el m\u00e1s experto de la biosfera en echar piedras sobre su propio tejado. Pero como tambi\u00e9n es el \u00fanico que tropieza numerosas veces ante el mismo obst\u00e1culo\u2026\u2026. Quiz\u00e1s por eso nos consideremos superiores al resto de los organismos \u00bfverdad?.<\/p>\n

Que placer trabajar sobre excelentes e innovadoras investigaciones, para variar de vez en cuando. \u00bfQu\u00e9 dir\u00e1n ahora los neodarvinistas? Me lo imagino: no saben, no contestan ni les importa o (\u2026.) todo gracias a la \u201cselecci\u00f3n natural\u201d \u00bf\u00bf??. No hay m\u00e1s ciego que el que no quiere ver, ni m\u00e1s sordo que el que no desea escuchar, justamente como los propios creacionistas.\u00a0<\/p>\n

Juan Jos\u00e9 Ib\u00e1\u00f1ez\u00a0<\/span>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/strong><\/p>\n

\u00a0<\/p>\n

Fungi Can Change Quickly And Pass Along Infectious Ability<\/a><\/strong><\/p>\n

Terradaily: by Staff Writers; Corvallis OR (SPX) Mar 24, 2010<\/span><\/strong><\/p>\n

Fungi have significant potential for \u00abhorizontal\u00bb gene transfer, a new study has shown, similar to the mechanisms that allow bacteria to evolve so quickly, become resistant to antibiotics and cause other serious problems<\/span><\/strong>.<\/p>\n

This discovery, to be published Thursday in the journal Nature<\/strong>, suggests that fungi have the capacity to rapidly change the make-up of their genomes and become infectious to plants and possibly animals, including humans<\/strong>.<\/p>\n

They are not nearly as confined to the more gradual processes of conventional evolution as had been believed<\/strong>, scientists say. And this raises issues not only for crop agriculture<\/strong> but also human health, because fungi are much closer on the \u00abevolutionary tree\u00bb to humans than bacteria, and consequently fungal diseases are much more difficult to treat<\/strong>.<\/p>\n

The genetic mechanisms fungi use to do this are different than those often used by bacteria<\/strong>, but the end result can be fairly similar. The evolution of virulence in fungal strains that was once believed to be slow has now been shown to occur quickly, and may force a renewed perspective on how fungi can behave, change and transfer infectious abilities.<\/p>\n

\u00abPrior to this we’ve believed that fungi were generally confined to vertical gene transfer or conventional inheritance, a slower type of genetic change based on<\/strong> the interplay of DNA mutation, recombination and the effects of selection,\u00bb said Michael Freitag, an assistant professor of biochemistry and biophysics at Oregon State University.<\/p>\n

\u00abBut in this study we found fungi able to transfer an infectious capability to a different strain in a single generation<\/strong>,\u00bb he said. \u00abWe’ve probably underestimated this phenomenon, and it indicates that fungal strains may become pathogenic faster than we used to think possible<\/strong>.\u00bb<\/p>\n

Researchers from the Center for Genome Research and Biocomputing at OSU collaborated on this study with a large international group of scientists, including principal investigators from The Broad Institute in Massachusetts, the University of Amsterdam, and the USDA Agricultural Research Service<\/strong> at the University of Minnesota.<\/p>\n

Bacteria use \u00abhorizontal\u00bb genetic transfer through chromosomes and DNA plasmids to change quickly<\/strong>, which is one reason that antibiotic resistance<\/strong> can often develop. This capability was believed to be possible, but rare, in fungi. In the new study<\/strong>, based on a genome-wide analysis of three Fusarium species<\/strong>, it was shown experimentally that complete chromosomes were being transferred between different fungal strains, along with the ability to cause infection. Various Fusarium fungi can infect both plants and humans<\/strong>.<\/p>\n

In humans, fungal infections are less common than those caused by bacteria, but<\/strong> can be stubborn and difficult to treat – in part, because fungi are far more closely related to animals, including humans, than are bacteria. That limits the types of medical treatments that can be used against them. Fungal infections are also a serious problem in people with compromised immune systems, including AIDS patients<\/strong>, and can be fatal.<\/p>\n

According to Freitag, this new understanding of fungal genetics and evolution is great news.<\/p>\n

For one thing, it may help researchers to better understand the types of fungal strains that are most apt to develop resistance to fungicides<\/strong>, and help crop scientists develop approaches to minimize that problem<\/strong>.<\/p>\n

Fungal diseases are a major problem in crop agriculture, and billions of dollars are spent<\/strong> around the world every year to combat new and emerging fungal pathogens in plants, animals and humans.<\/p>\n

On a more basic level, this study provides evidence that the \u00abtree of life,\u00bb with one trunk and many branches, is outdated. It should be replaced by a \u00abnetwork of life\u00bb in which many horizontal connections occur between different species<\/strong>.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

Como la mayor\u00eda de vosotros sab\u00e9is, los organismos del suelo que atesoran una mayor biodiversidad resultan ser las bacterias y los hongos. Si bien se sab\u00eda que el flujo horizontal de genes entre las bacterias era muy frecuente, no se sospechaba lo mismo en el universo f\u00fangico, ya que se pensaba que este mecanismo era ocasional en relaci\u00f3n a la herencia vertical. Nuevo varapalo para los untraneodarwinistas. \u00a1Qu\u00e9 la vamos a hacer! Ahora resulta, que habr\u00eda que reanalizar cuales son los mecanismos gen\u00e9ticos dominantes en las comunidades del suelo, ya que la noticia que el 24\/3\/2010 ofreci\u00f3 Terradaily, cuestiona las\u2026<\/p>\n","protected":false},"author":26,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0},"categories":[596,608,594,591,592],"tags":[46749,46750,46753,46745],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":4}},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/135838"}],"collection":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/users\/26"}],"replies":[{"embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/comments?post=135838"}],"version-history":[{"count":12,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/135838\/revisions"}],"predecessor-version":[{"id":136075,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/135838\/revisions\/136075"}],"wp:attachment":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/media?parent=135838"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/categories?post=135838"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/tags?post=135838"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}