Research Article
Identification of bapA in Strains of Salmonella
enterica subsp. enterica Isolated from Wild Animals
Kept in Captivity in Sinaloa, Mexico
Gabriela Silva-Hidalgo,
1
Martin López-Valenzuela,
1
Nora Cárcamo-Aréchiga,
1
Silvia Cota-Guajardo,
1
Mayra López-Salazar,
1
and Edith Montiel-Vázquez
2
1
Pathology Laboratory, Faculty of Veterinary Medicine and Animal Husbandry, Autonomous University of Sinaloa,
Boulevard San
´
Angel s/n, Fraccionamiento San Benito, 80246 Culiac´ an, SIN, Mexico
2
Enteric Bacteriology Laboratory, Institute of Epidemiological Diagnosis and Reference, Francisco de P. Miranda 177,
Lomas de Plateros,
´
Alvaro Obreg´ on, 01480 Mexico City, DF, Mexico
Correspondence should be addressed to Gabriela Silva-Hidalgo; gabsilhid@uas.edu.mx
Received 30 January 2016; Accepted 16 May 2016
Academic Editor: Remo Lobetti
Copyright © 2016 Gabriela Silva-Hidalgo et al. Tis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
bapA, previously named stm2689, encodes the BapA protein, which, along with cellulose and fmbriae, constitutes bioflms. Bioflms
are communities of microorganisms that grow in a matrix of exopolysaccharides and may adhere to living tissues or inert surfaces.
Bioflm formation is associated with the ability to persist in diferent environments, which contributes to the pathogenicity of
several species. We analyzed the presence of bapA in 83 strains belonging to 17 serovars of Salmonella enterica subsp. enterica from
wildlife in captivity at Culiacan’s Zoo and Mazatl´ an’s Aquarium. Each isolate amplifed a product of 667 bp, which corresponds to
the expected size of the bapA initiator, with no observed variation between diferent serovars analyzed. bapA gene was found to be
highly conserved in Salmonella and can be targeted for the genus-specifc detection of this organism from diferent sources. Since
bapA expression improves bacterial proliferation outside of the host and facilitates resistance to disinfectants and desiccation, the
survival of Salmonella in natural habitats may be favored. Tus, the risk of bacterial contamination from these animals is increased.
1. Introduction
Bioflms, composed of cellulose, fmbriae, and bioflm-
associated protein A (BapA, encoded by bapA), are com-
munities of microorganisms that grow in a matrix of
exopolysaccharides and can adhere to inert surfaces or living
tissues [1]. Bioflm formation is associated with the ability
to persist in diferent environments [2], which contributes
to the pathogenicity of several species [3]. It has been
shown that bacteria growing in bioflms are more resistant
to antimicrobial agents than those growing in planktonic
cultures due to their physical structure and the formation
of multilayer bioflms [4]. Whereas acute bacterial infections
can be eliminated afer a brief antibiotic treatment, infections
by bioflm-producing bacteria normally fail to be completely
eliminated and lead to recurrent infections, which can only
be resolved by replacing the initial antibiotic therapy [3].
Salmonella are rod-shaped bacteria commonly found in
bioflms [5]. Tis genus includes fagellated, Gram-negative
bacteria without spores that thrive in animals’ digestive tracts
and environments that facilitate long periods of survival,
which makes elimination difcult [6].
Fimbriae, or pili, are important for bioflm formation by
Salmonella [7]. Tese protein structures recognize a wide
range of molecular targets, allowing the bacteria to interact
with various surfaces and adhere to specifc tissues in the
host [8]. For example, type 1 fmbriae are thin, rigid, adhe-
sive structures that express FimH adhesins, which promote
bacterial adhesion to and invasion of epithelial cells [9]. Type
1 fmbriae also mediate interactions with abiotic surfaces [9].
Hindawi Publishing Corporation
Veterinary Medicine International
Volume 2016, Article ID 3478746, 4 pages
http://dx.doi.org/10.1155/2016/3478746