Biosciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Lett Appl Microbiol. 2010 Apr;50(4):431-7. doi: 10.1111/j.1472-765X.2010.02821.x. Epub 2010 Feb 8.
We will validate sample collection methods for recovery of microbial evidence in the event of accidental or intentional release of biological agents into the environment.
We evaluated the sample recovery efficiencies of two collection methods - swabs and wipes - for both nonvirulent and virulent strains of Bacillus anthracis and Yersinia pestis from four types of nonporous surfaces: two hydrophilic surfaces, stainless steel and glass, and two hydrophobic surfaces, vinyl and plastic. Sample recovery was quantified using real-time qPCR to assay for intact DNA signatures. We found no consistent difference in collection efficiency between swabs or wipes. Furthermore, collection efficiency was more surface-dependent for virulent strains than nonvirulent strains. For the two nonvirulent strains, collection efficiency was similar between all four surfaces, albeit B. anthracis Sterne exhibited higher levels of recovery compared to Y. pestis A1122. In contrast, recovery of B. anthracis Ames spores and Y. pestis CO92 from the hydrophilic glass or stainless steel surfaces was generally more efficient compared to collection from the hydrophobic vinyl and plastic surfaces.
Our results suggest that surface hydrophobicity may play a role in the strength of pathogen adhesion. The surface-dependent collection efficiencies observed with the virulent strains may arise from strain-specific expression of capsular material or other cell surface receptors that alter cell adhesion to specific surfaces.
These findings contribute to the validation of standard bioforensics procedures and emphasize the importance of specific strain and surface interactions in pathogen detection.
我们将验证在环境中意外或故意释放生物制剂时用于回收微生物证据的样本采集方法。
我们评估了两种采集方法——拭子和擦拭物——对来自四种非多孔表面的两种非毒性和毒性炭疽芽孢杆菌和鼠疫耶尔森氏菌菌株的样本回收效率：两种亲水表面，不锈钢和玻璃，以及两种疏水表面，乙烯基和塑料。使用实时 qPCR 检测完整 DNA 特征来定量样品回收。我们发现拭子或擦拭物之间的收集效率没有一致差异。此外，对于毒性菌株，收集效率比非毒性菌株更依赖于表面。对于两种非毒性菌株，所有四种表面的收集效率相似，尽管炭疽芽孢杆菌 Sterne 的回收水平高于鼠疫耶尔森氏菌 A1122。相比之下，从亲水玻璃或不锈钢表面收集炭疽芽孢杆菌 Ames 孢子和鼠疫耶尔森氏菌 CO92 的回收率通常高于从疏水乙烯基和塑料表面收集的回收率。
我们的结果表明，表面疏水性可能在病原体附着强度中起作用。对于毒性菌株观察到的依赖表面的收集效率可能源于荚膜物质或其他细胞表面受体的菌株特异性表达，这些物质改变了细胞对特定表面的粘附。
这些发现有助于标准生物取证程序的验证，并强调了特定菌株和表面相互作用在病原体检测中的重要性。
