Structure and properties of the outer membranes of Brucella abortus and Brucella melitensis Authors Ignacio Moriyón Departamento de Microbiología, Universidad de Navarra, Pamplona, Spain Ignacio López-Goñi Departamento de Microbiología, Universidad de Navarra, Pamplona, Spain Keywords: Brucella abortus, Brucella melitensis, outer membrane (OM), lipopolysaccharide (LPS), bacterial pathogenicity Abstract The brucellae are Gram-negative bacteria characteristically able to multiply facultatively within phagocytic cells and which cause a zoonosis of world-wide importance. This article reviews the structure and topology of the main components (lipopolysaccharide, native hapten polysaccharide, free lipids and proteins) of the outer membranes of Brucella abortus and B. melitensis, as well as some distinctive properties (permeability and interactions with cationic peptides) of these membranes. On these data, an outer membrane model is proposed in which, as compared to other Gram-negatives, there is a stronger hydrophobic anchorage for the lipopolysaccharide, free lipids, porin proteins and lipoproteins, and a reduced surface density of anionic groups, which could be partially or totally neutralized by ornithine lipids. This model accounts for the permeability of Brucella to hydrophobic permeants and for its resistance to the bactericidal oxygen-independent systems of phagocytes. Downloads PDF Published 2010-03-18 Issue Vol. 1 No. 1 (1998) 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.