Polymerase chain reaction (PCR)-based typing analysis of atypical isolates of the fish pathogen Aeromonas salmonicida.
Two hundred and five isolates of atypical Aeromonas salmonicida, recovered from a wide range of hosts and countries were characterized by polymerase chain reaction (PCR) targeting four genes. The chosen genes were those encoding the extracellular A-layer protein (AP), the serine protease (Sprot), the glycerophospholipid:cholestrol acetyltransferase protein (GCAT), and the 16S rRNA (16S rDNA). All the atypical A. salmonicida isolates could be assigned to 4 PCR groups. Group 1 comprised 45 strains which tested positive for PCR amplification, using the 16S rDNA, GCAT2, Sprot2, and AP primer-sets. Group 2 comprised 88 strains with produced PCR products using the 16S rDNA, GCAT2 and AP primer-sets. Group 3 comprised 21 strains which produced PCR products using 16S rDNA, GCAT2 and Sprot2 primer-sets, and group 4 comprised 51 strains which produced PCR products using the 16S rDNA and GCAT2 primer-sets only. A. salmonicida subsp. salmonicida isolates tested, belonged to group 1. The PCR primer-sets separated A. salmonicida from other reference strains of Aeromonas species and related bacteria with the exception of Aeromonas hydrophila. The results indicated that PCR typing is a useful framework for characterization of the increasing number of isolations of atypical A. salmonicida.
Høie
S
S
Department of Fish Health, National Veterinary Institute, Oslo, Norway. Steinar.Hoie@ld.dep.no
Dalsgaard
I
I
Aase
I L
IL
Heum
M
M
Thornton
J M
JM
Powell
R
R
D000217:Acyltransferases / Q000235:genetics; D000333:Aeromonas / Q000145:classification* / Q000201:enzymology / Q000235:genetics; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D005399:Fishes / Q000382:microbiology*; D005798:Genes, Bacterial; D008049:Lipase / Q000235:genetics; D016133:Polymerase Chain Reaction; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D012697:Serine Endopeptidases / Q000235:genetics
D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D000217:Acyltransferases; C085461:Aeromonas hydrophilia lipase-acyltransferase; D008049:Lipase; D012697:Serine Endopeptidases