La Duc Myron T, Sumner Randall, Pierson Duane, Venkat Parth, Venkateswaran Kasthuri
Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
Habitation (Elmsford). 2004;10(1):39-48. doi: 10.3727/154296604774808883.
Molecular analyses were carried out on four preflight and six postflight International Space Station (ISS)-associated potable water samples at various stages of purification, storage, and transport, to ascertain their associated microbial diversities and overall microbial burdens. Following DNA extraction, PCR amplification, and molecular cloning procedures, rDNA sequences closely related to pathogenic species of Acidovorax, Afipia, Brevundimonas, Propionibacterium, Serratia, and others were recovered in varying abundance. Retrieval of sequences arising from the iodine (biocide)-reducing Delftia acidovorans in postflight waters is also of concern. Total microbial burdens of ISS potable waters were derived from data generated by an ATP-based enumeration procedure, with results ranging from 0 to 4.9 x 10(4) cells/ml. Regardless of innate biases in sample collection and analysis, such circumstantial evidence for the presence of viable, intact pathogenic cells should not be taken lightly. Implementation of new cultivation approaches and/or viability-based assays are requisite to confirm such an occurrence.
对四个飞行前和六个飞行后与国际空间站（ISS）相关的饮用水样本在净化、储存和运输的各个阶段进行了分子分析，以确定其相关的微生物多样性和总体微生物负荷。经过DNA提取、PCR扩增和分子克隆程序后，回收了与嗜酸菌属、阿菲普菌属、短波单胞菌属、丙酸杆菌属、沙雷氏菌属等致病物种密切相关的rDNA序列，其丰度各不相同。飞行后水样中出现可还原碘（杀菌剂）的食酸戴尔福特菌产生的序列也令人担忧。国际空间站饮用水的总微生物负荷来自基于ATP计数程序生成的数据，结果范围为0至4.9×10⁴个细胞/毫升。无论样本采集和分析中存在何种固有偏差，对于存在有活力、完整的致病细胞的这种间接证据都不应掉以轻心。实施新的培养方法和/或基于活力的检测方法对于确认这种情况是必要的。
