Abstract:
An Enterobacterial repetitive intergenic consensus (ERIC)-PCR technique was used
for subtyping of 106 Aeromonas strains from Thailand and Italy. All 106 strains fall
into 80 genomic ERIC patterns (P1-P80), where ERIC pattern P1 represent by 6
strains (5.7 %) were predominant, followed by ERIC pattern P76 (4 strains), then
ERIC pattern P30, P70, P71 (3 strains each), ERIC pattern P2, P3, P4, P11, P32, P50,
P55, P58, P68 and P75 (2 strains each), and the rest of the strains have one strain each.
Twenty clinical Aeromonas strains from Thailand, were fall into 11 ERIC patterns
(pattern P1-P11), for eighty five environmental strains and one reference strain from
Italy, were fall into 69 ERIC patterns (P12-P80). All Aeromonas strains could be
grouped based on their genetic distance and geographic distribution of the strains, into
3 major clusters, cluster A, cluster B and cluster C, that contained 9, 30 and 41 ERIC
PCR patterns, with 18, 38 and 50 strains respectively. There appears to be
geographically restricted of ERIC patterns among Aeromonas strains from Thailand,
in that 85% of clinical strains from Thailand that fall in to ERIC pattern P1-P5, P8, P9
and P11, have closed genetic similarity and fall in to the same cluster of cluster A.
Except three Thai strains that fall in to ERIC pattern P6, P7 and P10, were in cluster C.
Cluster B contained 38 environmental strains from Italy, which 52% came from river
sediment of F. Basento river and 48% came from brackish water of L. Miseno lagoon.
Cluster C contained 47 environmental strains from Italy, which 77% came from river
sediment of F. Basento river, only 19% came from brackish water from L. Miseno
lake, this cluster also contained 3 clinical strains from Thailand. There was no
correlation between ERIC patterns and host, collection time, antibiotic resistant
profiles, also no correlation between ERIC patterns and biochemical profiles of the
strains.