Una consecuencia a considerar cuando se realiza el tratamiento biológico de aguas residuales que contienen compuestos aromáticos como el ácido tereftálico es la generación de una enorme cantidad de biomasa o lodos residuales.La problemática asociada a los lodos aparece cuando éstos dejan de ser un producto para convertirse en un residuo. Los procesos de tratamiento diseñados para lograr una reducción de bacterias pueden incurrir en capital substancial y altos costos de operación. El desarrollo del tratamiento de lodos con bacteriófagos puede proporcionar un control efectivo del costo a largo plazo de bacterias potencialmente patógenas. Las bacteriófagos son virus que infectan y lisan bacterias. Aquí la potencial aplicación de las técnicas con fagos es en los sistemas de tratamiento de aguas residuales para mejorar las emisiones de efluentes y lodos al ambiente. El propósito principal de este proyecto fue el aislar y el caracterizar bacteriófagos capaces de lisar a las bacterias degradadoras de ácido tereftálico, Arthrobacter sp. y Brevundimonas sp, de diversas fuentes de suelo y cuerpos de agua para el contro biólogico de éstas. Un bacteriófago capaz de lisar a Arthrobacter fue aislado de una muestra de suelo. Este fago fue caracterizado morfológicamente usando Microscopía Electrónica de Transmisión (TEM) y molecularmente utilizando técnicas de biología molecular. Algunos fragmentos del genoma del fago, generados por digestión con enzimas de restricción, fueron clonados en el vector pBlueScript II KS y posteriormente secuenciados y analizados. Las Imágenes de TEM mostraron fagos con cápsides isométricas y cola larga no contráctil, similares a las que presentan plataforma basal descritas para la familia siphoviridae del orden de los caudovirales. Dos de los fragmentos del genoma secuenciados y analizados muestran símilaridad con los genes de una proteína encargada de mediar la longitud de la cola de dos bacteriofagos que infectan a bacterias de los generos Gordonia y Rhodococcus. La similitud de estos fragmentos fue de 36-41%, la cual es baja y podría sugerir que el fago aislado está relacionado con los fagos que infectan a los generos mencionados pero no muestran una alta similitud con genomas de bacteriofagos previamente reportados por lo que el fago aislado en el presente trabajo y aquí reportado podría tratarse de un nuevo bacteriofago de Arthrobacter sp.
One of the aspect to consider when bio treating residual waters containing aromatic compounds such as tereftalic acid is the high biomass generated in the treatment. There is a problem when the sludge generated is no longer a product but a residue. Treatment of this sludge, to reduce bacterial number mainly, is costly. Treatment of residual sludge with bacteriophages could represent and effective and inexpensive process to reduce the number of potentially pathogenic bacteria. Bacteriophages are viruses that infect and lyse bacteria specifically and could then be used to lyse bacteria that are present at high number in residual sludge. The main objective of the present thesis was to isolate and characterize bacteriophages from diverse sources of soil and water capable of lysing tereftalic acid-degrading bacteria Arthrobactersp and Brevundimonas sp. Such bacteriophages could then be used to biologically control their growth. A bacteriophage capable of infecting Arthrobactersp was isolated from a soil sample. Using Transmission Electron Microscopy and DNA sequencing the isolated phage was characterized. Some DNA fragments from the phage´s genome, generated by restriction digestion, were cloned into vector pBlueScript II KS and sequenced. TEM images showed phages with isometric capsids and long non-contractile tails, similar to the basal platforms described for the family siphoviridae of the order caudovirales. Two of the DNA fragments sequenced from the phage´s genome showed similarity with the genes coding for a protein in charge of modulating the tail´s length in bacteriophages that infect bacteria of the genus Gordonia and Rhodococcus. The similarity was in the order of 36-41%, which is considered low and may suggest that the isolated phage is related to the bacteriophages that infect bacteria of the mentioned genus but not identical to any reported previously, thus could be a new phage discovered for Arhrobacter. sp.
One of the aspect to consider when bio treating residual waters containing aromatic compounds
such
as tereftalic acid is the
high biomass generated in the treatment. There is a problem when
the sludge generated is no longer a product but a residue. Treatment of this sludge, to reduce
bacterial number mainly, is costly. Treatment of residual sludge with
bacteriophages could
represent and effective and inexpensive process to reduce the number of potentially pathogenic
bacteria. Bacteriophages are viruses that infect and lyse bacteria specifically and could then be
used to lyse bacteria that are present at
high number in residual sludge. The main objective of
the present thesis was to isolate and characterize bacteriophages from diverse sources of soil
and water capable of lysing tereftalic acid-degrading bacteria
Arthrobactersp
and
Brevundimonas sp
. Such
bacteriophages could then be used to biologically control their growth.
A bacteriophage capable of infecting
Arthrobactersp
was isolated from a soil sample. Using
Transmission Electron Microscopy and DNA sequencing the isolated phage was characterized.
Some DNA
fragments from
the phage ́s genome, generated by restriction digestion,
were cloned into vector pBlueScript II KS and sequenced. TEM images showed phages with
isometric capsids and long non-contractile tails, similar to the basal platforms described for the
family
siphoviridae
of the order
caudovirales. Two of the DNA fragments sequenced from the
phage ́s genome showed similarity with the genes coding for a protein in charge of modulating
the tail ́s length in bacteriophages that infect bacteria of the genus
Gordonia
and
Rhodococcus
.
The similarity was in the order of 36-41%, which is considered low and may suggest that the
isolated phage is related to the bacteriophages that infect bacteria of the mentioned genus but
not identical to any reported previously, thus could be a new phage discovered for
Arhrobacter. sp
