Detection of virulence factors from Aeromonas Spp. In relation to diarrhea
2
Issued Date
2004
Resource Type
Language
eng
Rights
Mahidol University
Suggested Citation
Busakorn Promsarin, Boonchuay Eampokalap, Srisin Khusmith, ศรีสิน คูสมิทธิ์, Orasa Suthienkul, Yuvadee Mahakunkijcharoen, ยุวดี มหาคุณกิจเจริญ (2004). Detection of virulence factors from Aeromonas Spp. In relation to diarrhea. Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/63408
Title
Detection of virulence factors from Aeromonas Spp. In relation to diarrhea
Abstract
Aeromonas is one of the bacteria commomly isolated from stools of diarrheal patients, however, their etological role in gastroenteritis is unclear, as many virulence factors produced by Aeromonas species were reported, their association with diarrhea has not been clearly linked. This study was to elucidate the presence of major virulence factors among different Aeromonas spp. During the period of study (2002 to 2003), A. hydrophila and A. sobria were the most common species isolated from stools of patients with diarrhea while A. trota and A. caviae were less frequent. Of which 120 randomly selected Aeromonas that included 30 isolates of each Aeromonas spp. were determined for hemolytic, cytotonic and cytotoxic activities. Hemolytic activity was detected by the presence of a clear zone around bacterial colony on sheep blood agar plate and the ability of the bacterial culture supernatant to rupture sheep erythrocytes. While cytotonic and cytotoxic activities were detected by Chinese hamster ovary (CHO) cell elongation assay and cytopathic effect to African green monkey kidney (Vero) cell, respectively. Beta(β)-hemolysis was shown by 85 (71%) from all isolates studied including all A. hydrophila, 27(90%) of A. sobria, 13(43%) of A. trota and 15(50%) of A. caviae. The ability of culture supernatant to rupture sheep erythrocytes was found in 52(43%) isolates, 26(87%) were A. hydrophila, 21(70%) A. sobria and 5(16%) A. trota. All isolates of A. caviae did not rupture sheep erythrocytes. A hydrophila and A. sobria showed higher hemolytic activity than A. trota. All β-hemolysis positive isolates were also rupture sheep erythrocytes. The cytotonic activity, 92(72%) isolates affect CHO cell elongation. A. hydrophila, A. sobria and A. trota contain more cytotonic strains (97%), while A. caviae gave the less number of cytotonic strains(17%). Study of the effect on Vero cell, 90(75%) isolates showed cytotoxic activity. All A. trota isolates and 97% of A. hydrophila and A. sobria were cytotoxic strains, but only 2 A. caviae showed cytotoxic activity. Taken together, 52(43%) isolates possess all 3 activities, i.e., 26(87%) A. hydrophila, 21(70%) A.sobria and 5(17%) A. trota. These results indicate that the extracellular products from diarrheagenic A. hydrophila and A. sobria were displayed hemolytic, cytotonic and cytotoxic activities. A. trota produced only cytotonic and cytotoxic activities, while A. caviae express lowest activities.
Description
Joint International Tropical Medicine Meeting 2004: Ambassador Hotel, Thailand 29 November-1 December 2004: abstract. Bangkok: Faculty of Tropical Medicine, Mahidol University; 2004. p.257.