USDA-ARS U. S. Salinity Laboratory, Riverside, CA 92507, United States; Department of Environmental Sciences, University of California, Riverside, CA 92521, United States.
USDA-ARS U. S. Salinity Laboratory, Riverside, CA 92507, United States.
Sci Total Environ. 2014 Aug 15;490:822-9. doi: 10.1016/j.scitotenv.2014.05.069. Epub 2014 Jun 5.
Shiga toxin producing Escherichia coli O157 and non-O157 serogroups are known to cause serious diseases in human. However, research on the persistence of E. coli non-O157 serogroups in preharvest environment is limited. In the current study, we compared the survival behavior of E. coli O157 to that of non-O157 E. coli strains in agricultural soils collected from three major fresh produce growing areas of California (CA) and Arizona (AZ). Results showed that the nonpathogenic E. coli O157:H7 4554 survived longer than the pathogenic E. coli O157:H7 EDL933 in Imperial Valley CA and Yuma AZ, but not in soils from the Salinas area. However, E. coli O157:NM was found to persist significantly longer than E. coli O157:H7 EDL933 in all soil tested from the three regions. Furthermore, two non-O157 (E. coli O26:H21 and E. coli O103:H2) survived significantly longer than E. coli O157:H7 EDL933 in all soils tested. Pearson correlation analysis showed that survival of the E. coli strains was affected by different environmental factors. Our data suggest that survival of E. coli O157 and non-O157 may be strain and soil specific, and therefore, care must be taken in data interpretation with respect to survival of this pathogen in different soils.
产志贺毒素大肠杆菌 O157 和非 O157 血清群已知会导致人类严重疾病。然而，关于食源性非 O157 血清群大肠杆菌在收获前环境中的持久性研究有限。在本研究中，我们比较了来自加利福尼亚州（CA）和亚利桑那州（AZ）三个主要新鲜农产品种植区的农业土壤中收集的大肠杆菌 O157 和非 O157 大肠杆菌菌株的生存行为。结果表明，非致病性大肠杆菌 O157:H7 4554 在加利福尼亚州帝国谷和亚利桑那州尤马的生存时间长于致病性大肠杆菌 O157:H7 EDL933，但在萨利纳斯地区的土壤中并非如此。然而，在三个地区所有测试的土壤中，大肠杆菌 O157:NM 比大肠杆菌 O157:H7 EDL933 持续存在的时间明显更长。此外，两种非 O157（大肠杆菌 O26:H21 和大肠杆菌 O103:H2）在所有测试的土壤中比大肠杆菌 O157:H7 EDL933 存活时间明显更长。Pearson 相关性分析表明，大肠杆菌菌株的存活受到不同环境因素的影响。我们的数据表明，大肠杆菌 O157 和非 O157 的存活可能与菌株和土壤特异性有关，因此，在解释该病原体在不同土壤中的存活时必须谨慎。
