Defensive and simultaneous actions of glycoconjugates during spore decontamination.

An estimated $1 billion was lost in decontaminating areas exposed to anthrax in the 2001 attacks. To counter the threat of biological attacks, an effective 'green' decontaminant is vital to minimize the consequences of such attacks. The objective of our research was to study the ability of glycoconjugate ligands to decontaminate Bacillus cereus spores on hard surfaces. Polyvalent glycoconjugates (also known as neoglycoconjugates) were tested during decontamination of B. cereus spores. Resulting colony forming units (CFU) of viable spores were a direct evidence of glycoconjugate decontamination efficacy. Our results indicate a substantial, decreasing CFU count due to defensive and simultaneous actions of glycoconjugates compared to spores only used as controls. Decontamination of B. cereus spores was most efficiently and consistently achieved using Galalpha1-->3GalNAcbeta-PAA-flu glycoconjugate under both defensive and simultaneous conditions. Atomic force microscopy (AFM) allowed us to visualize decontamination at the nanoscale level using glycoconjugates. AFM reveals the size of glycoconjugate agglomerates (clusters) and a noticeably different morphology of glycoconjugate-treated spores during decontamination. Morphological features of untreated spores disappear under a thin layer of glycoconjugate solution. This thin layer is formed due to the defensive action of glycoconjugates. Simultaneous action has shown agglomeration of glycoconjugates in solution with B. cereus spores in glycoconjugate suspensions. Glycoconjugates might be useful for the development of an environment-friendly decontaminant of bacterial spores.