Please use this identifier to cite or link to this item:
Title: Behavior of an Aeromonas hydrophila aroA live vaccine in water microcosms
Authors: Vivas, José
Carracedo, Begoña
Riaño, Jorge
Razquin, Blanca E.
López-Fierro, Pilar
Acosta, Félix 
Naharro, Germán
Villena, Alberto J.
Keywords: Natural Mineral-Water
Trout Oncorhynchus-Mykiss
Ulcerative Syndrome Eus
Nonculturable Cells, et al
Issue Date: 2004
Publisher: 0099-2240
Journal: Applied and Environmental Microbiology 
Abstract: Genetically modified auxotrophic mutants of different fish pathogens have been used as live vaccines in laboratory experiments, but the behavior of the strains after release into aquatic ecosystems has not been characterized. We previously constructed and characterized an aroA mutant of Aeromonas hydrophila and studied the protection afforded by this mutant as a live vaccine in rainbow trout. In this work we describe the survival of this strain in aquatic microcosms prepared from fish water tanks. The aroA mutant disappeared rapidly in nonfiltered, nonautoclaved fish tank water, declining below detection levels after 15 days, suggesting an inhibitory effect of the autochthonous microflora of the water. When the aroA strain was used to inoculate sterilized water, its culturability was lower than that of wild-type strain A. hydrophila AG2; after long periods of incubation, aroA cells were able to enter a viable but nonculturable state. Entry into this nonculturable state was accompanied by changes in the cell morphology from rods to spheres, but the cells appeared to remain potentially viable, as assessed by the preservation of cell membrane integrity. Supplementation of the culture medium with sodium pyruvate favored the culturability and resuscitation of the two A. hydrophila strains at low temperatures (6 and 16degreesC). These results contribute to a better understanding of the behavior of the aroA strain in natural environments and suggest that the inactivation of the aroA gene may be beneficial for the safety of this live vaccine for aquacultures.
ISSN: 0099-2240
DOI: 10.1128/AEM.70.5.2702-2708.2004
Source: Applied and Environmental Microbiology[ISSN 0099-2240],v. 70, p. 2702-2708
Appears in Collections:Artículos
Show full item record


checked on Aug 14, 2022


checked on Aug 14, 2022

Page view(s)

checked on May 21, 2022

Google ScholarTM




Export metadata

Items in accedaCRIS are protected by copyright, with all rights reserved, unless otherwise indicated.