TY - JOUR
T1 - Inability of some aeromonas hydrophila strains to act as recipients of plasmid pRAS1 in conjugal transfer experiments
AU - Bello-López, Juan Manuel
AU - Vázquez-Ocampo, Noemi Judith
AU - Fernández-Rendón, Elizabeth
AU - Curiel-Quesada, Everardo
N1 - Funding Information:
This work was partially supported by grant CGPI-IPN 20101081. JMBL was awarded a CONACyT fellowship. Everardo Curiel-Quesada and Elizabeth Fernández-Rendón are COFAA fellows.
PY - 2012/4
Y1 - 2012/4
N2 - Plasmids belonging to the IncU incompatibility group are mobile genetic elements isolated frequently from Aeromonas spp. These plasmids share structural and functional characteristics and often carry Class-1 integrons bearing antibiotic resistance genes. In this work the ability of two IncU plasmids, pAr-32 and pRAS1 to establish in different A. hydrophila strains after conjugal transfer was studied. In vitro transfer frequencies on solid surface ranged from 10 -1 to 10 -6 for pAr-32 and from 10 -3 to 10 -5 for pRAS1. While carrying out these experiments we detected four strains unable to acquire plasmid pRAS1, indicating that the genetic background of recipients affects the establishment of the plasmid. We explored the possible reasons why these strains failed to yield transconjugants after mating experiments using A. salmonicida 718 as a donor. Factors included donor cell recognition, incompatibility, surface exclusion and restriction of incoming DNA. We found that none of these factors could explain the refractivity of non-receptive A. hydrophila strains to yield transconjugants. Although we do not know the reasons of this refractivity, we may speculate that these isolates lack a product necessary to replicate or stabilize plasmid pRAS1. Alternatively, these strains could contain a product that impedes plasmid establishment.
AB - Plasmids belonging to the IncU incompatibility group are mobile genetic elements isolated frequently from Aeromonas spp. These plasmids share structural and functional characteristics and often carry Class-1 integrons bearing antibiotic resistance genes. In this work the ability of two IncU plasmids, pAr-32 and pRAS1 to establish in different A. hydrophila strains after conjugal transfer was studied. In vitro transfer frequencies on solid surface ranged from 10 -1 to 10 -6 for pAr-32 and from 10 -3 to 10 -5 for pRAS1. While carrying out these experiments we detected four strains unable to acquire plasmid pRAS1, indicating that the genetic background of recipients affects the establishment of the plasmid. We explored the possible reasons why these strains failed to yield transconjugants after mating experiments using A. salmonicida 718 as a donor. Factors included donor cell recognition, incompatibility, surface exclusion and restriction of incoming DNA. We found that none of these factors could explain the refractivity of non-receptive A. hydrophila strains to yield transconjugants. Although we do not know the reasons of this refractivity, we may speculate that these isolates lack a product necessary to replicate or stabilize plasmid pRAS1. Alternatively, these strains could contain a product that impedes plasmid establishment.
UR - http://www.scopus.com/inward/record.url?scp=84860241271&partnerID=8YFLogxK
U2 - 10.1007/s00284-011-0076-1
DO - 10.1007/s00284-011-0076-1
M3 - Artículo
C2 - 22228423
SN - 0343-8651
VL - 64
SP - 332
EP - 337
JO - Current Microbiology
JF - Current Microbiology
IS - 4
ER -