Endospore surface properties of commonly used Bacillus anthracis surrogates vary in aqueous solution

• Published in: Antonie van Leeuwenhoek Vol. 106; no. 2; pp. 243 - 251
• Main Authors: White, Colin P, Popovici, Jonathan, Lytle, Darren A, Rice, Eugene W
• Format: Journal Article
• Language: English
• Published: Cham Springer-Verlag 01.08.2014; Springer International Publishing; Springer Nature B.V
• Subjects: Aqueous solutions; Bacillus - chemistry; Bacillus anthracis; Biomedical and Life Sciences; buffers; Drinking water; electrophoresis; electrostatic interactions; Electrostatics; endospores; Gram-positive bacteria; Hydrophobic surfaces; hydrophobicity; infrastructure; Life Sciences; Medical Microbiology; Microbiology; Microorganisms; Original Paper; Plant Sciences; Soil Science & Conservation; Solutions; Spores, Bacterial - chemistry; Surface Properties; tap water; virulence; Endospores; Hydrophobicity; Surrogate; Anthrax; Electrophoretic mobility; Surface
• ISSN: 0003-6072; 1572-9699
• DOI: 10.1007/s10482-014-0187-3

The hydrophobic character and electrophoretic mobility (EPM) of microorganisms are vital aspects of understanding their interactions with the environment. These properties are fundamental in fate-and-transport, physiological, and virulence studies, and thus integral in surrogate selection. Hydrophobic and electrostatic forces are significant contributors to particle and microorganism mobility in the environment. Herein, the surface properties of commonly used Bacillus anthracis surrogate endospores were tested under comparable conditions with respect to culture, endospore purification, buffer type and strength. Additionally, data is presented of endospores suspended in dechlorinated tap water to evaluate the surrogates in regard to a breach of water infrastructure security. The surface properties of B. anthracis were found to be the most hydrophobic and least electronegative among the six Bacillus species tested across buffer strength. The effect of EPM on hydrophobicity varies in a species-specific manner. This study demonstrates that surrogate surface properties differ and care must be taken when choosing the most suitable surrogate. Moreover, it is shown that Bacillus thuringensis best represents Bacillus anthracis-Sterne with respect to both EPM and hydrophobicity across all test buffers.