[et_pb_section fb_built=”1″ _builder_version=”4.16″ global_colors_info=”{}”][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” custom_padding=”5px|0px|0|0px|false|false” make_fullwidth=”on” locked=”off” global_colors_info=”{}” column_structure=”2_3,1_3″ width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”2_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”|700|||||||” text_text_color=”#256168″ text_font_size=”44px” text_line_height=”1.1em” text_font_size_tablet=”” text_font_size_phone=”33px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n
Detection and enumeration methods<\/p>\n
[\/et_pb_text][et_pb_text _builder_version=”4.23.1″ text_font=”||||||||” text_text_color=”#256168″ text_font_size=”25px” text_line_height=”1.1em” background_color=”#eaeddb” custom_margin=”|||” custom_padding=”60px|60px|60px|95px|true” custom_padding_tablet=”60px|50px|60px|50px|true|true” custom_padding_phone=”40px|50px|40px|50px|true|true” custom_padding_last_edited=”on|tablet” hover_enabled=”0″ text_font_size_tablet=”” text_font_size_phone=”20px” text_font_size_last_edited=”on|phone” locked=”off” global_colors_info=”{}” sticky_enabled=”0″]<\/p>\n
4.1<\/strong> Methods based on direct observation of host cell lysis<\/a> [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n Before starting to look at detection and enumeration, we should perhaps talk a little bit about sampling and conservation of the samples<\/strong>. When taking a sample the ideal situation would probably be to do the analyses as soon as possible, but the tests can be delayed<\/strong>, if needed, by 48-72 hours<\/strong> as long as the samples are kept at 4\u00baC<\/strong>. It is easy to concentrate phages from volumes up to one liter, and small volumes can keep their phage density for months<\/strong> when stored at -20\u00baC, or -80\u00baC after adding 10% v\/v glycerol.<\/strong><\/p>\n [\/et_pb_text][et_pb_button button_url=”http:\/\/www.ub.edu\/ubtv\/cerca\/?cercar=bacteriophage” url_new_window=”on” button_text=”access video content” button_alignment=”left” _builder_version=”4.16″ custom_padding=”10px|50px|10px|50px|true|true” global_colors_info=”{}” button_text_size__hover_enabled=”off” button_one_text_size__hover_enabled=”off” button_two_text_size__hover_enabled=”off” button_text_color__hover_enabled=”off” button_one_text_color__hover_enabled=”off” button_two_text_color__hover_enabled=”off” button_border_width__hover_enabled=”off” button_one_border_width__hover_enabled=”off” button_two_border_width__hover_enabled=”off” button_border_color__hover_enabled=”off” button_one_border_color__hover_enabled=”off” button_two_border_color__hover_enabled=”off” button_border_radius__hover_enabled=”off” button_one_border_radius__hover_enabled=”off” button_two_border_radius__hover_enabled=”off” button_letter_spacing__hover_enabled=”off” button_one_letter_spacing__hover_enabled=”off” button_two_letter_spacing__hover_enabled=”off” button_bg_color__hover_enabled=”off” button_one_bg_color__hover_enabled=”off” button_two_bg_color__hover_enabled=”off”][\/et_pb_button][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/coliphages.com\/wp-content\/uploads\/2018\/09\/cta-bluephage.jpg” url=”http:\/\/bluephage.com\/” url_new_window=”on” align_tablet=”center” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}” align_phone=”center”][\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” make_fullwidth=”on” global_colors_info=”{}” width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.2em” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n When working with bacteriophages, we do not need to worry about phenomena such as stress, injury or reactivation that frequently lead to misinterpretation of environmental data on bacterial indicators.<\/p>\n All of the above makes it easy to work with phages as an indicator.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”28px” text_line_height=”1.3em” background_color=”#f0f1ec” custom_margin=”|||||true” custom_padding=”50px|50px|70px|50px||true” custom_padding_tablet=”” custom_padding_phone=”50px|30px|50px|30px|true|true” custom_padding_last_edited=”on|phone” text_font_size_tablet=”” text_font_size_phone=”21px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n The detection and enumeration of an infectious<\/strong> (living) bacteriophage depends on the fact that they lyse a susceptible host cell<\/strong>.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n \u00a0It is possible to detect the presence of phage genomes or fragments of genome by nucleic acid amplification techniques such as PRC. However, the detection of whole genomes<\/strong> or fragments of genome in a sample does not guarantee that they correspond to phages which are still alive<\/strong> and hence capable of infecting and replicating in a susceptible host cell.<\/p>\n Lysis<\/strong> of a host cell can be detected by<\/strong> visual observation due to the decrease in opacity<\/strong> of a matrix containing the host cells. This can be seen either by the appearance of clear areas<\/strong> in an opaque solid layer<\/strong> of host cells (see figures 1 and 2) or by a decrease in the optical density<\/strong> of a liquid suspension<\/strong> of host cells.<\/p>\n It is also possible to detect host cell lysis<\/strong> by detecting the appearance of an intracellular enzyme in the supernatant that has been released by lysis<\/strong>.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.23.1″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” hover_enabled=”0″ text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}” module_id=”4-1″ sticky_enabled=”0″]<\/p>\n Nowadays, standardized methods for the detection and enumeration of bacteriophages are based on this principle. They can be quantitative<\/strong> methods and presence\/absence<\/strong> methods (Adams, 1959).<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ background_color=”#f0f1ec” width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” custom_padding=”|||” make_fullwidth=”on” global_colors_info=”{}” column_structure=”1_2,1_2″ width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”1_2″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/coliphages.com\/wp-content\/uploads\/2018\/09\/01detection-ok.png” force_fullwidth=”on” align_tablet=”center” align_last_edited=”on|desktop” _builder_version=”4.16″ custom_margin=”30px|0px||0px||true” custom_margin_tablet=”” custom_margin_phone=”0px|||” custom_margin_last_edited=”on|phone” custom_padding=”|||30px” custom_padding_tablet=”” custom_padding_phone=”0px|20px|0px|20px|true|true” custom_padding_last_edited=”on|phone” global_colors_info=”{}” align_phone=”center”][\/et_pb_image][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.3em” custom_margin=”20px|40px|20px||true” custom_margin_tablet=”” custom_margin_phone=”|20px||20px||true” custom_margin_last_edited=”on|phone” text_font_size_tablet=”” text_font_size_phone=”15px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n Quantitative methods<\/strong> are those that allow direct quantification<\/strong> of infectious viral particles in a sample<\/strong>. The number of viruses is visible when making a culture consisting of an agar<\/strong> monolayer containing both bacteria<\/strong> and the sample<\/strong> that may contain bacteriophages. After incubation<\/strong> on a Petri plate, we can observe clear areas of different sizes where turbidity<\/strong> (a typical feature of Petri plates where there is a mass bacterial culture) is lost due to cell destruction<\/strong>. Each clear area (called a plaque)<\/strong> is caused by a bacteriophage<\/strong> (or clump of bacteriophages). When counting<\/strong>, we speak about plaque-forming units (PFUs)<\/strong> instead of saying an absolute number of viruses as it is possible that the virions attach to one another, and thus an agglomerate of more than one bacteriophage can only attack one bacterium. In some literature PFUs can also be called PFPs (plaque-forming particles).<\/p>\n [\/et_pb_text][et_pb_button button_url=”https:\/\/www.youtube.com\/watch?v=ddbaul2ijw8″ url_new_window=”on” button_text=”access video content” button_alignment=”center” _builder_version=”4.16″ custom_margin=”||10px||false” custom_padding=”10px|50px|10px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|30px||30px||true” custom_padding_last_edited=”on|phone” global_colors_info=”{}” button_text_size__hover_enabled=”off” button_one_text_size__hover_enabled=”off” button_two_text_size__hover_enabled=”off” button_text_color__hover_enabled=”off” button_one_text_color__hover_enabled=”off” button_two_text_color__hover_enabled=”off” button_border_width__hover_enabled=”off” button_one_border_width__hover_enabled=”off” button_two_border_width__hover_enabled=”off” button_border_color__hover_enabled=”off” button_one_border_color__hover_enabled=”off” button_two_border_color__hover_enabled=”off” button_border_radius__hover_enabled=”off” button_one_border_radius__hover_enabled=”off” button_two_border_radius__hover_enabled=”off” button_letter_spacing__hover_enabled=”off” button_one_letter_spacing__hover_enabled=”off” button_two_letter_spacing__hover_enabled=”off” button_bg_color__hover_enabled=”off” button_one_bg_color__hover_enabled=”off” button_two_bg_color__hover_enabled=”off”][\/et_pb_button][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” make_fullwidth=”on” global_colors_info=”{}” width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.2em” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n The two main quantitative methods<\/strong> are single agar layer (SAL)<\/strong> and double agar layer (DAL)<\/strong>. Both SAL and DAL are based on the appearance of plaques<\/strong> on an agar layer made of semisolid agar, a culture containing the desired bacterial strain, and the problem sample. After incubation overnight<\/strong> the plaques can be observed in the agar plate if there are bacteriophages in the sample. The difference between the two methods is that DAL has an extra solid agar layer under the semisolid<\/strong> one that makes a more stable base for the second layer, which is an advantage in situations where the Petri plates are in a bad state or made of poor quality materials. For the results obtained to be statistically valid<\/strong>, the number of PFUs on a Petri plate<\/strong> has to be between 30 and 300<\/strong>. This is why it is recommendable to make<\/strong> several dilutions<\/strong> of the sample before starting the procedure.<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ background_color=”#f0f1ec” width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” custom_padding=”|||0px” make_fullwidth=”on” locked=”off” global_colors_info=”{}” column_structure=”1_2,1_2″ width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”1_2″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/coliphages.com\/wp-content\/uploads\/2018\/08\/02detection.png” force_fullwidth=”on” align_tablet=”center” align_last_edited=”on|desktop” _builder_version=”4.16″ custom_margin=”|||0px” custom_margin_tablet=”” custom_margin_phone=”” custom_margin_last_edited=”on|phone” custom_padding=”|20px||20px” global_colors_info=”{}” align_phone=”center”][\/et_pb_image][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.3em” custom_margin=”20px|40px|20px||true” custom_margin_tablet=”” custom_margin_phone=”|20px||20px||true” custom_margin_last_edited=”on|phone” text_font_size_tablet=”” text_font_size_phone=”15px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n The presence\/absence methods<\/strong> are those that, by themselves, only indicate<\/strong> whether or not there are bacteriophages<\/strong> in a given volume of the tested sample<\/strong>. The traditional presence\/absence method is the spot test<\/strong>, which consists of putting a drop<\/strong> of a decontaminated aliquot of an enrichment culture<\/strong> on a Petri plate where previously we cultured bacteria. After incubating<\/strong>, the place where the drop was put loses its turbidity due to cell destruction if there are bacteriophages<\/strong> in the sample. The enrichment culture consists of a liquid culture of the host bacteria, inoculated with an aliquot of a sample and incubated for a number of hours.<\/p>\n [\/et_pb_text][et_pb_button button_url=”https:\/\/www.youtube.com\/watch?v=W8nOklhhEw4″ url_new_window=”on” button_text=”Access video content” button_alignment=”center” _builder_version=”4.16″ custom_padding=”10px|50px|10px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|20px||20px||true” custom_padding_last_edited=”on|phone” global_colors_info=”{}” button_text_size__hover_enabled=”off” button_one_text_size__hover_enabled=”off” button_two_text_size__hover_enabled=”off” button_text_color__hover_enabled=”off” button_one_text_color__hover_enabled=”off” button_two_text_color__hover_enabled=”off” button_border_width__hover_enabled=”off” button_one_border_width__hover_enabled=”off” button_two_border_width__hover_enabled=”off” button_border_color__hover_enabled=”off” button_one_border_color__hover_enabled=”off” button_two_border_color__hover_enabled=”off” button_border_radius__hover_enabled=”off” button_one_border_radius__hover_enabled=”off” button_two_border_radius__hover_enabled=”off” button_letter_spacing__hover_enabled=”off” button_one_letter_spacing__hover_enabled=”off” button_two_letter_spacing__hover_enabled=”off” button_bg_color__hover_enabled=”off” button_one_bg_color__hover_enabled=”off” button_two_bg_color__hover_enabled=”off”][\/et_pb_button][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” make_fullwidth=”on” global_colors_info=”{}” width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n This kind of method does not allow direct quantification, but the number of infectious viral particles can be determined using quantal (statistics-based) methods<\/strong>. The most used of them is MPN (most probable number)<\/strong> which consists of making presence\/absence tests with different amounts (or dilutions) of the sample and making several replicas of each amount (or dilution) of sample to determine, using statistics, the amount of virus in a certain volume of sample<\/strong>. This kind of method increases their sensitivity when increasing the number of replicas performed, until the point that they can be as accurate as quantitative methods.<\/p>\n [\/et_pb_text][et_pb_button button_url=”https:\/\/www.youtube.com\/user\/melodyscrudato\/videos?shelf_id=0&view=0&sort=dd” url_new_window=”on” button_text=”access video content” button_alignment=”left” _builder_version=”4.16″ custom_padding=”10px|60px|10px|60px|true|true” custom_padding_tablet=”” custom_padding_phone=”|30px||30px||true” custom_padding_last_edited=”on|phone” global_colors_info=”{}” button_text_size__hover_enabled=”off” button_one_text_size__hover_enabled=”off” button_two_text_size__hover_enabled=”off” button_text_color__hover_enabled=”off” button_one_text_color__hover_enabled=”off” button_two_text_color__hover_enabled=”off” button_border_width__hover_enabled=”off” button_one_border_width__hover_enabled=”off” button_two_border_width__hover_enabled=”off” button_border_color__hover_enabled=”off” button_one_border_color__hover_enabled=”off” button_two_border_color__hover_enabled=”off” button_border_radius__hover_enabled=”off” button_one_border_radius__hover_enabled=”off” button_two_border_radius__hover_enabled=”off” button_letter_spacing__hover_enabled=”off” button_one_letter_spacing__hover_enabled=”off” button_two_letter_spacing__hover_enabled=”off” button_bg_color__hover_enabled=”off” button_one_bg_color__hover_enabled=”off” button_two_bg_color__hover_enabled=”off”][\/et_pb_button][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” make_fullwidth=”on” global_colors_info=”{}” width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.23.1″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” hover_enabled=”0″ text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}” module_id=”4-2″ sticky_enabled=”0″]<\/p>\n These methods are based on the discharge of intracellular enzymes to the growth medium when the bacteria lyse<\/strong>. This kind of method requires identifying easy-to-detect intracellular enzymes, such as adenylate kinase and adenosine 5\u2019-triphosphate, \u03b2-galactosidase and \u03b2- glucuroronidase, for which chromogenic or fluorogenic substrates are available (Guzman et al. 2009, Salter et al., 2010, Muniesa et al., 2018)<\/p>\n At present this procedure is only applicable to liquid suspension<\/strong> and hence for presence\/absence<\/strong> determination. However, as explained in the previous section, accurate quantal methods such as most probable number (MPN)<\/strong>, can be used.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.23.1″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” hover_enabled=”0″ text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” global_colors_info=”{}” module_id=”4-3″ sticky_enabled=”0″]<\/p>\n Based on these principles, the following standardized methods are available for bacteriophages proposed or being used as indicators. The key feature of standardized methods is the host bacteria selected for the method.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” background_color=”#f0f1ec” custom_padding=”50px|50px|50px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”30px|30px|30px|30px|true|true” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n International Standardization Organization.<\/strong> Water Quality\u2014Detection and Enumeration of Bacteriophages\u2014Part 1: Enumeration of F-specific RNA Bacteriophages; ISO-10705-1; International Standardization Organization: Geneva, Switzerland, 1995.<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” custom_padding=”|50px||50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|0px||0px||true” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n International Standardization Organization.<\/strong> Water Quality\u2014Detection and Enumeration of Bacteriophages\u2014Part 2: Detection and Enumeration of Somatic Coliphages; ISO-10705-2; International Standardization Organization: Geneva, Switzerland, 2000.<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” background_color=”#f0f1ec” custom_padding=”50px|50px|50px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”30px|30px|30px|30px|true|true” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n USEPA Office of Water.<\/strong> Method 1601: Male-specific (F+) and Somatic Coliphage in Water by Two-step Enrichment Procedure; EPA 821-R-01-030; USEPA Office of Water: Washington, DC, USA, 2001.<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” custom_padding=”|50px||50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|0px||0px||true” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n USEPA Office of Water.<\/strong> Method 1601: Male-specific (F+) and Somatic Coliphage in Water by Two-step Enrichment Procedure; EPA 821-R-01-030; USEPA Office of Water: Washington, DC, USA, 2001.<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” background_color=”#f0f1ec” custom_padding=”50px|50px|50px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”30px|30px|30px|30px|true|true” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n USEPA Office of Water<\/strong>. Method 1602: Male-specific (F+) and Somatic Coliphage in Water by Single Agar Layer (SAL) Procedure; EPA 821-R-01-029; USEPA Office of Water: Washington, DC, USA, 2001.<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” custom_margin=”||0px|” custom_padding=”0px|50px|0px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|||0px” custom_padding_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n Rice, E.W.,Baird, R.B., Eaton, A.D. and Clesceri, L.S. Standard Methods for the Examination of Water and Wastewater<\/strong>; American Public Health Association, American Water Works Association, Water Environment Federation. Washington, DC, USA, 2012<\/em>.<\/p>\n \u00a0<\/em><\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”18px” text_line_height=”1.2em” background_color=”#f0f1ec” custom_padding=”50px|50px|50px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”30px|30px|30px|30px|true|true” custom_padding_last_edited=”on|phone” locked=”off” global_colors_info=”{}”]<\/p>\n International Standardization Organization.<\/strong> Water Quality\u2014Detection and Enumeration of Bacteriophages-Part 4: Detection and enumeration of bacteriophages infecting Bacteroidesfragilis; ISO-10705-2 International Standardization Organization, Geneva, Switzerland, 2001<\/em><\/p>\n [\/et_pb_text][et_pb_divider _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_divider][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_line_height=”1.3em” header_font=”||||||||” header_2_font=”|700|||||||” header_2_text_color=”#0a2d31″ header_2_font_size=”33px” text_font_size_tablet=”” text_font_size_phone=”18px” text_font_size_last_edited=”on|phone” locked=”off” global_colors_info=”{}”]<\/p>\n Some emerging detection methods are based on the detection of an enzyme released by cell lysis into the liquid matrix where phage infection of a host cell occurs. These methods appear to be simple, fast, cost-effective and as accessible as user-friendly kits.<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”28px” text_line_height=”1.2em” background_color=”#f0f1ec” text_orientation=”center” custom_margin=”|||||true” custom_padding=”50px|50px|70px|50px||true” custom_padding_tablet=”” custom_padding_phone=”50px|30px|50px|30px|true|true” custom_padding_last_edited=”on|phone” text_font_size_tablet=”” text_font_size_phone=”21px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n BLUEPHAGE is a method based on this principle for which engineered host cells have been designed to increase the specificity, sensitivity and speed of the procedure<\/strong>.<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” custom_padding=”31.7833px|0px|4px|0px|false|false” make_fullwidth=”on” global_colors_info=”{}” width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_divider divider_weight=”2px” _builder_version=”4.16″ max_width=”20%” global_colors_info=”{}”][\/et_pb_divider][et_pb_text _builder_version=”4.16″ text_font=”|700|||||||” text_text_color=”#256168″ text_font_size=”33px” global_colors_info=”{}”]<\/p>\n References<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_font_size=”15px” text_line_height=”1.3em” background_color=”#eaeddb” custom_padding=”50px|50px|50px|50px|true|true” custom_padding_tablet=”” custom_padding_phone=”|30px||30px||true” custom_padding_last_edited=”on|phone” text_font_size_tablet=”” text_font_size_phone=”12px” text_font_size_last_edited=”on|phone” global_colors_info=”{}”]<\/p>\n Adams, M.H. (1959).<\/em> Bacteriophages<\/strong>. Interscience Publishers Inc. New York.<\/p>\n Guzm\u00e1n Luna, C., Cost\u00e1n-Longares, A., Lucena, F. and Jofre, J.<\/em> Detection of somatic coliphages through a bioluminescence assay measuring phage mediated release of adenylate kinase and adenosine 5\u2019-triphosphate<\/strong>. J. Virol. Methods 2009, 161, 107\u2013113.<\/p>\n Salter, R.S. and Durbin, G.W.<\/em> Modified USEPA method 1601 to indicate viral contamination of groundwater<\/strong>. J. Am. Water Works Assoc. 2012, 104, 480\u2013488.<\/p>\n Muniesa, M., Ballest\u00e9, E., Imamovic, L., Pascula-Benito, M., Toribio-Avedillo, D., Lucena, F.and and Jofre, J. 2018<\/em>. Bluephage: A rapid method for the detection of somatic coliphages used as indicators of fecal pollution in water<\/strong>. Water Research 128: 10-19.<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”3.12.1″ background_color=”#256168″ custom_padding=”33px|0px|0|0px|false|false” global_module=”97″ saved_tabs=”all” global_colors_info=”{}”][et_pb_row module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ width=”89%” width_tablet=”80%” width_last_edited=”on|desktop” max_width=”89%” max_width_tablet=”80%” max_width_last_edited=”on|desktop” module_alignment=”center” custom_margin=”0px|||” custom_padding=”0px||0||false|false” make_fullwidth=”on” global_colors_info=”{}” column_structure=”1_3,1_3,1_3″ width_phone=”80%” max_width_phone=”80%”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”||30px|” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/coliphages.com\/wp-content\/uploads\/2019\/05\/logo-coliphages.png” show_bottom_space=”off” align=”right” align_tablet=”center” align_last_edited=”on|desktop” _builder_version=”4.16″ custom_margin=”0px|||” custom_padding=”|30px|30px|” global_colors_info=”{}” align_phone=”center”][\/et_pb_image][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/coliphages.com\/wp-content\/uploads\/2018\/09\/ub-mars.png” align_tablet=”center” align_last_edited=”on|desktop” _builder_version=”4.16″ custom_margin=”30px|||30px” global_colors_info=”{}” align_phone=”center”][\/et_pb_image][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_sidebar area=”sidebar-4″ disabled_on=”on|on|off” _builder_version=”4.16″ header_font=”|700|||||||” header_text_color=”#dce09a” header_font_size=”16px” background_layout=”dark” custom_margin=”40px|||30px” global_colors_info=”{}”][\/et_pb_sidebar][\/et_pb_column][\/et_pb_row][\/et_pb_section]<\/p>\n","protected":false},"excerpt":{"rendered":" Detection and enumeration methods 4.1 Methods based on direct observation of host cell lysis4.2 Methods based on the determination of molecules released by cell lysis4.3 Specific methodsBefore starting to look at detection and enumeration, we should perhaps talk a little bit about sampling and conservation of the samples. When taking a sample the ideal situation […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-209","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/pages\/209","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/comments?post=209"}],"version-history":[{"count":67,"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/pages\/209\/revisions"}],"predecessor-version":[{"id":952,"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/pages\/209\/revisions\/952"}],"wp:attachment":[{"href":"https:\/\/coliphages.com\/index.php\/wp-json\/wp\/v2\/media?parent=209"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
4.2<\/strong> Methods based on the determination of molecules released by cell lysis<\/a>
4.3<\/strong> Specific methods<\/a><\/p>\n4.1 Methods based on direct observation of host cell lysis<\/h2>\n
4.2 Methods based on the determination of molecules released by cell lysis<\/h2>\n
4.3 Specific methods<\/h2>\n
Standardized methods<\/em><\/h3>\n
Emerging methods<\/em><\/h3>\n