Small acid-soluble spore proteins

B. anthracis and related species.41,44 6 Some of these peaks have been identified (e.g., as small acid soluble spore proteins and cyclic lipopeptides), but others remain uncharacterized. There is no agreement among different laboratories as to which markers are suitable for chemotaxonomic differentiata-tion of species (i.e., are consistently found in one species versus another) or for strain identification (i.e., are reproducibly found in one strain but not another). Further, although it might be anticipated that surface proteins can be preferentially ionized or extracted, the ultra-structural origin of some peptides within the cell is not always clear. 

Senthilkumar K, Grozema FC, Guerra CF, Bickelhaupt FM, Siebbeles LDA (2003) Mapping the sites for selective oxidation of guanines in DNA. J Am Chem Soc 125 13658-13659 Setlow B, Setlow P (1993) Binding of small, acid-soluble spore proteins to DNA plays a significant role in the resistance of Bacillus subtilis spores to hydrogen peroxide. Appl Environ Microbiol... 

Moeller R, Setlow P, Reitz G, Nicholson WL. Roles of small, acid-soluble spore proteins and core water content in survival of Bacillus subtilis spores exposed to environmental solar UV radiation. Appl Environ Microbiol. 2009 75(16) 5202 8. doi 10.1128/AEM.00789-09. 

Setlow P. Small, acid-soluble spore proteins of Bacillus species structure, synthesis, genetics, function, and degradation. Ann Rev Microbiol. 1988 42 319-38. doi 10.1146/annurev. mi.42.100188.001535. 

Swatkoski S, Russell SC, Edwards N, Fenselau C. Rapid chemical digestion of small acid-soluble spore proteins for analysis of Bacillus spores. Anal Chem. 2006 78 181-8. 

DNA in spores is densely packed and covered by small acid-soluble spore proteins. The DNA is strongly dehydrated and exits in a more A-Hke conformation. This dense packing enables spores to survive even extreme conditions like extreme cold and heat or severe dryness. Irradiation of spores with UV Kght causes formation of yet another photolesion, which is exclusively formed in spores, possibly due to the unusual A-like conformation of the DNA. > The formation of this lesion (Scheme 5) can be mimicked by irradiation of a thin film of dry thymine or of a frozen thymidine solution with a UV-C hght source (254 nm), as depicted in Scheme 6(a). ... 

Hathout, Y. Setlow, B. Cabrera-Martinez, R. M. Fenselau, C. Small, acid-soluble proteins as biomarkers in mass spectrometry analysis of Bacillus spores. Appl. Environ. Microbiol. 2003,69,1100-1107. 

Various reasons have been put forward as to why the spore is less sensitive to H202 than the vegetative cell. In the spore, the DNA is covered by the so-called small acid-soluble proteins (SASP) instead of water which makes it relatively inaccessible to oxidative damage as these SASPs may provide compaction besides sacrificial protection (e.g., Setlow 1994,1995 Setlow and Setlow 1993). 

The UV-induced generation of cyclobutane dimers is greatly dependent on double-helix conformational factors. In dormant spores of various bacillus species, for example, a group of small, acid-soluble proteins specifically bind to DNA, thereby enforcing a particular conformation that is unfavorable for the formation of harmful cyclobutane-type lesions. As a consequence, these dormant spores are much more resistant to UV radiation than the corresponding grooving cells, in which DNA strands reassume conformations favorable for the formation of cyclobutane-type lesions [31]. 

Demirev, R, Ramirez, J. and Fenselau, C., Tandem mass spectrometry of intact proteins for characterization of biomarkers from Bacillus cereus T spores. Anal. Chent, 73, 5725-5731 (2001). Hathout, Y., Setlow, B., Cabrera-Martinez, R.M., Eenselau, C. and Setlow R, Small, acid-soluble proteins as biomarkers in mass spectrometry analysis of Bacillus spores. Appl. Environ. Microbiol., 69, 1100-1107 (2003). 

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