La Duc Myron T, Osman Shariff, Vaishampayan Parag, Piceno Yvette, Andersen Gary, Spry J A, Venkateswaran Kasthuri
Biotechnology and Planetary Protection, NASA Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 89, Oak Grove Dr., Pasadena, CA 91109, USA.
Appl Environ Microbiol. 2009 Oct;75(20):6559-67. doi: 10.1128/AEM.01073-09. Epub 2009 Aug 21.
A census of clean room surface-associated bacterial populations was derived from the results of both the cloning and sequencing of 16S rRNA genes and DNA microarray (PhyloChip) analyses. Samples from the Lockheed Martin Aeronautics Multiple Testing Facility (LMA-MTF), the Kennedy Space Center Payload Hazard and Servicing Facility (KSC-PHSF), and the Jet Propulsion Laboratory Spacecraft Assembly Facility (JPL-SAF) clean rooms were collected during the various assembly phases of the Phoenix and Mars Science Laboratory (MSL) spacecraft. Clone library-derived analyses detected a larger bacterial diversity prior to the arrival of spacecraft hardware in these clean room facilities. PhyloChip results were in agreement with this trend but also unveiled the presence of anywhere from 9- to 70-fold more bacterial taxa than cloning approaches. Among the facilities sampled, the JPL-SAF (MSL mission) housed a significantly less diverse bacterial population than either the LMA-MTF or KSC-PHSF (Phoenix mission). Bacterial taxa known to thrive in arid conditions were frequently detected in MSL-associated JPL-SAF samples, whereas proteobacterial lineages dominated Phoenix-associated KSC-PHSF samples. Comprehensive bacterial censuses, such as that reported here, will help space-faring nations preemptively identify contaminant biomatter that may compromise extraterrestrial life detection experiments. The robust nature and high sensitivity of DNA microarray technologies should prove beneficial to a wide range of scientific, electronic, homeland security, medical, and pharmaceutical applications and to any other ventures with a vested interest in monitoring and controlling contamination in exceptionally clean environments.
通过对16S rRNA基因的克隆和测序以及DNA微阵列（PhyloChip）分析的结果，得出了洁净室表面相关细菌种群的普查数据。在凤凰号和火星科学实验室（MSL）航天器的各个组装阶段，采集了来自洛克希德·马丁航空航天多重测试设施（LMA-MTF）、肯尼迪航天中心有效载荷危险与服务设施（KSC-PHSF）以及喷气推进实验室航天器组装设施（JPL-SAF）洁净室的样本。基于克隆文库的分析在航天器硬件抵达这些洁净室设施之前检测到了更大的细菌多样性。PhyloChip的结果与这一趋势一致，但也揭示出细菌分类群的数量比克隆方法多出9至70倍。在所采样的设施中，JPL-SAF（MSL任务）中的细菌种群多样性明显低于LMA-MTF或KSC-PHSF（凤凰号任务）。在与MSL相关的JPL-SAF样本中经常检测到已知在干旱条件下繁衍生息的细菌分类群，而与凤凰号相关的KSC-PHSF样本中则以变形菌谱系为主。像本文所报告的这种全面的细菌普查，将有助于航天国家预先识别可能会影响外星生命探测实验的污染生物物质。DNA微阵列技术的强大特性和高灵敏度应该会对广泛的科学、电子、国土安全、医疗和制药应用以及任何其他对在极其洁净的环境中监测和控制污染有既得利益的项目有益。
