Biochemical identification and numerical taxonomy of Aeromonas spp. isolated from environmental and clinical samples in Spain.
OBJECTIVE
To study the phenotypic characteristics of Aeromonas spp. from environmental and clinical samples in Spain and to cluster these strains by numerical taxonomy.


RESULTS
A collection of 202 Aeromonas strains isolated from bivalve molluscs, water and clinical samples was tested for 64 phenotypic properties; 91% of these isolates were identified at species level. Aeromonas caviae was predominant in bivalve molluscs and Aerom. bestiarum in freshwater samples. Cluster analyses revealed eight different phena: three containing more than one DNA-DNA hybridization group but including strains that belong to the same phenospecies complex (Aerom. hydrophila, Aerom. sobria and Aerom. caviae), Aerom. encheleia, Aerom. trota and three containing unidentified Aeromonas strains isolated from bivalve molluscs.


CONCLUSIONS
Aeromonas spp. are widely distributed in environmental and clinical sources. A selection of 16 of the phenotypical tests chosen allowed the identification of most isolates (91%), although some strains remain unidentified, mainly isolates from bivalve molluscs, suggesting the presence of new Aeromonas species. Numerical taxonomy was not in total concordance with the identification of the studied strains.


CONCLUSIONS
Numerical taxonomy of Aeromonas strains isolated from different sources revealed the presence of potentially pathogenic Aeromonas spp., especially in bivalve molluscs, and phena with unidentified strains that suggest new Aeromonas species.
Miñana-Galbis
D
D
Departament Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Divisió IV, Universitat de Barcelona, Barcelona, Spain.
Farfán
M
M
Lorén
J G
JG
Fusté
M C
MC
D000333:Aeromonas / Q000145:classification* / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D015373:Bacterial Typing Techniques; D002965:Classification / Q000379:methods; D005618:Fresh Water / Q000382:microbiology*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology*; D006168:Guinea Pigs; D006801:Humans; D008974:Mollusca / Q000382:microbiology*; D009693:Nucleic Acid Hybridization; D010641:Phenotype; D015203:Reproducibility of Results; D013030:Spain