Rapid and low-level toxic PCR-based method for routine identification of Flavobacterium psychrophilum Authors Catalina Cepeda Department of Microbiology and Parasitology, Faculty of Biology, University of Santiago de Compostela, Spain Ysabel Santos Department of Microbiology and Parasitology, Faculty of Biology, University of Santiago de Compostela, Spain Keywords: Flavobacterium psychrophilum, low toxicity, methylene blue, vertical electrophoresis, fish pathogenic bacteria Abstract We describe a rapid, low-toxicity and simple method for the detection of the bacterial fish pathogen Flavobacterium psychrophilum. The method, based on the polymerase chain reaction (PCR), combined the electrophoresis of PCR products in a vertical agarose gel and a modified methylene blue stain. DNA was amplified directly either from bacterial suspensions or from tissues experimentally infected with F. psychrophilum, using different non-toxic commercial DNA extraction kits. The protocol allowed to detect 15 to 150 cells of the pathogen in bacterial suspension, without prior DNA extraction, and 7500 to 75,000 cells in seeded spleen tissue and ovarian fluid using Dynabeads DNA DIRECT extraction system. This method, which has the advantage of not using hazardous products, is proposed as a fast tool for routine identification of F. psychrophilum. Downloads PDF Published 2010-03-14 Issue Vol. 3 No. 4 (2000) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.