TY - JOUR
T1 - Antimicrobial susceptibilities of Aeromonas spp. isolated from environmental sources
AU - Huddleston, Jennifer R.
AU - Zak, John C.
AU - Jeter, Randall M.
PY - 2006/11
Y1 - 2006/11
N2 - Aeromonas spp. are ubiquitous aquatic bacteria that cause serious infections in both poikilothermic and endothermic animals, including humans. Clinical isolates have shown an increasing incidence of antibiotic and antimicrobial drug resistance since the widespread use of antibiotics began. A total of 282 Aeromonas pure cultures were isolated from both urban and rural playa lakes in the vicinity of Lubbock, Texas, and several rivers in West Texas and New Mexico. Of these, at least 104 were subsequently confirmed to be independent isolates. The 104 isolates were identified by Biolog and belonged to 11 different species. The MICs of six metals, one metalloid, five antibiotics, and two antimicrobial drugs were determined. All acromonads were sensitive to chromate, cobalt, copper, nickel, zinc, cefuroxime, kanamycin, nalidixic acid, oioxacin, tetracycline, and sulfamethoxazole. Low incidences of trimethoprim resistance, mercury resistance, and arsenitc resistance were found. Dual resistances were found in 5 of the 104 Aeromonas isolates. Greater numbers of resistant isolates were obtained from samples taken in March versus July 2002 and from sediment versus water. Plasmids were isolated from selected strains of the arsenite- and mercury-resistant organisms and were transformed into Escherichia coli XL1-Blue MRF'. Acquisition of the resistance phenotypes by the new host showed that these resistance genes were carried on the plasmids. Mercury resistance was found to be encoded on a conjugative plasmid. Despite the low incidence of resistant isolates, the six playa lakes and three rivers that were sampled in this study can be considered a reservoir for antimicrobial resistance genes.
AB - Aeromonas spp. are ubiquitous aquatic bacteria that cause serious infections in both poikilothermic and endothermic animals, including humans. Clinical isolates have shown an increasing incidence of antibiotic and antimicrobial drug resistance since the widespread use of antibiotics began. A total of 282 Aeromonas pure cultures were isolated from both urban and rural playa lakes in the vicinity of Lubbock, Texas, and several rivers in West Texas and New Mexico. Of these, at least 104 were subsequently confirmed to be independent isolates. The 104 isolates were identified by Biolog and belonged to 11 different species. The MICs of six metals, one metalloid, five antibiotics, and two antimicrobial drugs were determined. All acromonads were sensitive to chromate, cobalt, copper, nickel, zinc, cefuroxime, kanamycin, nalidixic acid, oioxacin, tetracycline, and sulfamethoxazole. Low incidences of trimethoprim resistance, mercury resistance, and arsenitc resistance were found. Dual resistances were found in 5 of the 104 Aeromonas isolates. Greater numbers of resistant isolates were obtained from samples taken in March versus July 2002 and from sediment versus water. Plasmids were isolated from selected strains of the arsenite- and mercury-resistant organisms and were transformed into Escherichia coli XL1-Blue MRF'. Acquisition of the resistance phenotypes by the new host showed that these resistance genes were carried on the plasmids. Mercury resistance was found to be encoded on a conjugative plasmid. Despite the low incidence of resistant isolates, the six playa lakes and three rivers that were sampled in this study can be considered a reservoir for antimicrobial resistance genes.
UR - http://www.scopus.com/inward/record.url?scp=33750996430&partnerID=8YFLogxK
U2 - 10.1128/AEM.00774-06
DO - 10.1128/AEM.00774-06
M3 - Article
C2 - 16950901
AN - SCOPUS:33750996430
SN - 0099-2240
VL - 72
SP - 7036
EP - 7042
JO - Applied and environmental microbiology
JF - Applied and environmental microbiology
IS - 11
ER -