Rosiles-González Gabriela, Ávila-Torres Gerardo, Moreno-Valenzuela Oscar A, Acosta-González Gilberto, Leal-Bautista Rosa María, Grimaldo-Hernández Cinthya D, Brown Judith K, Chaidez-Quiroz Cristóbal, Betancourt Walter Q, Gerba Charles P, Hernández-Zepeda Cecilia
Unidad de Ciencias del Agua, Centro de Investigación Científica de Yucatán A.C., Calle 8, No 39, Mz 29, SM 64, CP 77524, Cancún, Quintana Roo, México.
Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán A.C., Calle 43, No 130, Col. Chuburná de Hidalgo, CP 97205, Mérida, Yucatán, México.
Food Environ Virol. 2017 Dec;9(4):487-497. doi: 10.1007/s12560-017-9309-1. Epub 2017 Jun 23.
The Yucatan Peninsula of Mexico hosts a karst aquifer system that is the only source of freshwater for the area; however, it is vulnerable to human-mediated contamination. Pepper mild mottle virus (PMMoV) is one of the most abundant RNA viruses associated with human feces, making it a viable indicator for tracking fecal pollution in aquatic environments, including groundwater. In this study, groundwater samples collected from a karst aquifer from fresh and brackish water locations were analyzed for fecal indicator bacteria, somatic and male F+ specific coliphages, and PMMoV during the rainy and dry seasons. Total coliform bacteria were detected at all sites, whereas Escherichia coli were found at relatively low levels <40 MPN/100 ml. The highest average concentrations of somatic and male F+ specific coliphages were 920 and 330 plaque forming units per 100 ml, respectively, detected in freshwater during the rainy season. PMMoV RNA was detected in 85% of the samples with gene sequences sharing 99-100% of nucleotide identity with PMMoV sequences available in GenBank. Quantification of PMMoV genome copies (GC) by quantitative real-time PCR indicated concentrations ranging from 1.7 × 10 to 1.0 × 10 GC/L, with the highest number of GC detected during the rainy season. No significant correlation was observed between PMMoV occurrence by season or water type (p > 0.05). Physicochemical and indicator bacteria were not correlated with PMMoV concentrations. The abundance and prevalence of PMMoV in the karst aquifer may reflect its environmental persistence and its potential as a fecal indicator in this karst aquifer system.
墨西哥的尤卡坦半岛拥有一个岩溶含水层系统，该系统是该地区唯一的淡水来源；然而，它易受人为污染的影响。辣椒轻斑驳病毒（PMMoV）是与人类粪便相关的最丰富的RNA病毒之一，使其成为追踪包括地下水在内的水生环境中粪便污染的可行指标。在本研究中，对从岩溶含水层的淡水和微咸水位置采集的地下水样本在雨季和旱季进行了粪便指示细菌、体细胞和雄性F+特异性大肠杆菌噬菌体以及PMMoV的分析。在所有地点均检测到总大肠菌群，而大肠杆菌的检出水平相对较低，<40 MPN/100 ml。在雨季淡水样本中检测到的体细胞和雄性F+特异性大肠杆菌噬菌体的最高平均浓度分别为每100 ml 920和330噬菌斑形成单位。在85%的样本中检测到PMMoV RNA，其基因序列与GenBank中可用的PMMoV序列具有99-100%的核苷酸同一性。通过定量实时PCR对PMMoV基因组拷贝（GC）进行定量分析，结果表明浓度范围为1.7×10至1.0×10 GC/L，在雨季检测到的GC数量最多。未观察到PMMoV的发生与季节或水类型之间存在显著相关性（p>0.05）。理化指标和指示细菌与PMMoV浓度无关。岩溶含水层中PMMoV的丰度和流行率可能反映了其在环境中的持久性及其作为该岩溶含水层系统中粪便指示物的潜力。
