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Bacillus anthracis spores are enclosed by an exosporium comprised of a basal layer and an external hair-like nap. The filaments of the nap are composed of trimers of the collagen-like glycoprotein Bc1A. The attachment of essentially all Bc1A trimers to the exosporium requires the basal layer protein BxpB, and both proteins are included in stable high-molecular-mass exosporium complexes. Bc1A contains a proteolytically processed 38-residue amino-terminal domain (NTD) that is essential for basaMayer attachment. In this report, we identify three NTD submotifs (SM1a, SM1b, and SM2, located within residues 21 to 33) that are important for Bc1A attachment and demonstrate that residue A20, the amino-terminal residue of processed Bc1A, is not required for attachment. We show that the shortest NTD of BclA--or of a recombinant protein--sufficient for high-level basal-layer attachment is a 10-residue motif consisting of an initiating methionine, an apparently arbitrary second residue, SM1a or SM1b, and SM2. We also demonstrate that cleavage of the Bc1A NTD is necessary for efficient attachment to the basal layer and that the site of cleavage is somewhat flexible, at least in certain mutant NTDs. Finally, we propose a mechanism for BclA attachment and discuss the possibility that analogous mechanisms are involved in the attachment of many different collagen-like proteins of B. anthracis and closely related Bacillus species. doi: 10.1128/JB.01003-09

Short metal-binding NP peptides were efficiently displayed and covalently anchored to the cell wall of Saccharomyces cerevisiae to enhance the biosorption capacity of the potential yeast biosorbent. The results revealed that the biosorption mechanism could be specifically upgraded with microprecipitation by engineering the biosorbent with an eligible metal-binding peptide.

The various effects of the wall structure, macromolecular composition and the surface polymers on the survival and hydrologic transport of Cryptosporidium parvum oocysts are determined. The strength of these oocsyt walls is shown to be highly dependent on an inner layer of glycoprotein.

Gram-positive bacteria are probed with conformationally specific antibodies and have disclosed the existence of extracellular functional bacterial amyloid (FuBA) in mycolata species, as well as six other specific antibodies belonging to the phyla Actinobacteria and Firmicutes. The studies have shown that amyloid is widespread among gram-positive bacteria and might constitute an integral part of the spore and the cellular envelope.