SASPs

SASPs comprise about 10-20% of the protein in the dormant spore, exist in two forms alfi and y) d are degraded during germination. They are essential for expression of spore resistance to ultraviolet radiation and also appear to be involved in resistance to some biocides, e.g. hydrogen peroxide. Spores (a /3 ) deficient in a//3-type SASPs are much more peroxide-sensitive than are wild-type (normal) spores. It has been proposed that in wild-type spores DNA is saturated with a/j3-type SASPs and is thus protected from free radical damage. 

As the result of theoretical consideration of polycondensation of an arbitrary mixture of such monomers it was proved [55,56] that the alternation of monomeric units along polymer molecules obey the Markovian statistics. If all initial monomers are symmetric, i.e. they resemble AaScrAa, units Sa(a=l,...,m) will correspond to the transient states of the Markov chain. The probability vap of transition from state Sa to is the ratio Q /v of two quantities Qa/9 and va which represent, respectively, the number of dyads (SaSp) and monads (Sa) per one monomeric unit. Clearly, Qa(S is merely a ratio of the concentration of chemical bonds of the u/i-ih type, formed as a result of the reaction between group Aa and Ap, to the overall concentration of monomeric units. The probability va0 of a transition from the transient state Sa to an absorbing state S0 equals l-pa where pa represents the conversion of groups Aa. 

As is the case with identifications based on protein molecular masses, it appears that the use of tryptic or other peptide masses as the basis for identification is extended with difficulty to mixtures of microorganisms. This reflects unpredictable suppression. Another limitation is redundancy of peptide masses across several microorganisms. For example, the most abundant proteins (SASPs), and thus the most abundant peptides, in spores of Bacillus anthracis and the closely related pesticide Bacillus thuringiensis have extensive sequence homology.25,82... 

Newer aminosalicylate preparations appear superior to placebo but differ little in efficacy from sulfasalazine SASP. Potential advantages in reduced adverse effects from removal of the sulfa moiety nevertheless may exist. 

In addition, alkylated aldehydes can be transformed to (—)-(5)-l-amino-2-(tcr/-butyldi-methylsilyloxymethyl)pyrrolidine (SASP)-hydrazones without racemization. The diastereomeric ratio of these hydrazones can be determined directly using HPLC. Furthermore, this method allows determination of the absolute configuration of the alkylated hydrazones, since SASP-hy-drazones of (S, -configuration always elute first11 25. 

To a solution of 0.25 mmol (58 mg) of f-)-(S )-l-amino-2-(/e/- -butyIdimelhylsilyloxymcthyi)pyrrolidinc (SASP) and 0.2 g of MgS04 in 2.5 mL of cyclohexane, 0.20 mmol of the aldehyde is added and stirred at r.t. for 20 min. The solution is filtered from the MgS04, the solvent is evaporated under reduced pressure, and the crude product is filtered through a Pasteur pipette filled with silica gel using petroleum ether/elhyl acetate (98 2). The diastereomeric excess (de, which is the ee of the aldehyde) is then determined by analytical HPLC using hexane/elhyl acetate/ isopropyl alcohol (99 1 0.2). 

Starting from racemic aldehydes, this method allows separation of the diastereomeric SASP-hy-drazones on a gram scale25. 

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). 

SASPs and is thus protected from free radical damage. The a ff mutants do not appear to have been tested against other biocides. In view of their postulated role in protecting DNA, it is interesting to speculate that a///-type SASPs would not be associated with spore resistance to those biocides that have little or no effect on DNA. 

Resolution of a-substituled aldehydes. The SASP hydrazones of a-substituted aldehydes can be resolved by high-performance liquid chromatography. The separahility factors are sufficient for analytical and preparative purposes. The (S,S)-isomer elutes consistently before the (S,R)-isomer. Both isomers can be cleaved to the enantiomerically pure aldehydes by ozonolysis or acid hydrolysis, with resolution yields of 35-70%. 

A) (i ll) the limit of x in C Asp appears to be ca. 10. Although Fig. 5 does not show it, the composition of the pure stage-two material, in which the other stage phases were not detectable by XRPD, was ca. C sAsP ,. These observations indicate that the vacuum stable C(,AsF salts with the 4 distance of ca. 7.6 -F3.35n A have the staging formula Ci AsFj. 

W. Bauer, in Lithium Chemistry—A Theoretical and Experimental Overview, edited by A.-M. Saspe and P. v. R. Schleyer, Wiley, Chichester, 1995, p. 125. 

Stohner, J., Quack, M. Quantities, Units and Symbols in Physical Chemistry. In Beck, R.D., Drabbels, M., Rizzo, T.R. (eds.) Contributions 16th Symposium on Atomic and Surface Physics and Related Topics (SASP 2008), p. 219-222. Innsbruck Univ. Press, Innsbruck (2008)... 

Figure 13.12 MALDI spectra of the tryptic digests generated in situ from (a) Bacillus subtilis 168, (b) Bacillus anthracis Sterne, (c) Bacillus cereus T, (d) Bacillus thuringiensis subs. Kurstaki HD-1 and (e) Bacillus globigii spores, and analyzed with the miniaturized TOF mass spectrometer. Peaks that were matched to peptides in the SASP database are numbered 1-39. Peaks that occur in more than one spectrum carry the same number. (Reprinted with permission from ref. 37).

Boscaini, E. Boschetti, A. Biasioli, F. Gallerani, G. Gasperi, F. Jordan, A. Lindinger, W. lannotta, S. Symposium on Atomic and Surface Physics and Related Topics, Trento, Italy, Jan. 30-Feb. 5, 2000 (www.science.unitn.it/sasp/index.html). 

Electronic Conductivity. Fluorides usually are good insulators owing to the wide band gap of more than 6 eV in most compounds. In some cases it is possible, however, to obtain n-type semiconducting properties by doping, for example, in Cdp2(Y). Exceptional metallic conductivity is observed in the metal-rich compound AgaP, even superconductivity in Hga-sAsPe - despite the presence of fluoride. Mixed-valence silver fluorides have been recently discussed as possible candidates for superconductivity. ... 

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