Polyglutamic acid from Bacillus anthracis grown in vivo: structure and aggressin activity

Abstract

Tomesik & Szongott (1933) obtained a nitrogenous, polysaccharide-free, capsular material from BacillU anthracis which was identified by Ivanovics & Bruckner (1937a, b) as poly-D-glutamic acid. A capsule is formed by virulent strains of B. anthracis and appears to be connected with the aggressive aspect of virulence, that is, with the ability of the pathogen to interfere with the defence mechanisms

Poly-γ-glutamic acid: production, properties and applications

“…anthracis is known to produce a pure D enantiomer of c-PGA (Zwartouw & Smith, 1956). The prominent difference in the mechanism of production of B. anthracis compared with other Bacillus species is that it does not secrete c-PGA into the medium, but instead, it is peptidoglycan bound.…”

“…The D enantiomer in B. anthracis capsule makes the bacterium non-immunogenic (Zwartouw & Smith, 1956). The c-PGA protects the bacterial cells against phage infections and also prevents antibodies from gaining access to the bacterium (Mesnage et al, 1998).…”

Characterization of new l,d-endopeptidase gene product CwlK (previous YcdD) that hydrolyzes peptidoglycan in Bacillus subtilis

“…These results indicate that h-∆CwlK is an L-alanoyl-D-glutamic acid endopeptidase. (Zwartouw and Smith 1956) and B. subtilis (natto) (Hara et al 1982) have poly-γ-glutamic acids as capsules and CwlK can hydrolyse the L-Ala-D-Glu bond in B. subtilis cell wall. Interestingly, YwtD, which was recently predicted to be a DL-endopeptidase (Smith et al 2000), was identified as an enzyme involved in γ-glutamic acid degradation (Suzuki and Tahara 2003).…”

Western blot analysis of the exotoxin components from Bacillus anthracis separated by isoelectric focusing gel electrophoresis

“…Finally, Namibia, an isolate that can overcome preexisting immunity in guinea pigs, and ST-I, a live vaccine isolate, had comparable LeTx cytotoxicity levels (32.6 and 28.1 ng/ml, respectively) and EdTx adenylate cyclase activity (6.99 and 7.48 pmol/lg protein, respectively). Thus, the ability of some isolates to override immunity in guinea pigs may be dependent upon other B. anthracis virulence factors, capsule production [35], surface composition of the spores as well as physiological characteristics of the animal itself.…”