Clostridia/Clostridium

Butanol Some clostridia Clostridium acetobutylicum Clostridium saccha roacetobutylicum... 

S.Red. Cl =Sulphite Reducing Clostridia—Clostridium welchii =Decimal logarithms of counts... 

Anaerobic sporulating clostridia (Clostridium perfringens) are much less frequent as compared with the coliforms. 

The carboxylic acid reductase in acetogenic Clostridia such as Clostridium thermoaceti-cum (White et al. 1989 Strobl et al. 1992). 

As for the aerobic degradation of pyridines, hydroxylation of the heterocyclic ring is a key reaction in the anaerobic degradation of azaarenes by Clostridia. Whereas in Clostridium barkeri, the end products are carboxylic acids, CO2, and ammonium, the anaerobic sulfate-reducing Desulfococcus niacinii degraded nicotinate completely to CO2 (Imhoff-Stuckle and Pfennig 1983), although the details of the pathway remain incompletely resolved. 

Partial reduction by Clostridia has been demonstrated and has already been discussed in Chapter 9, Part 5. The effectiveness of Clostridia in the anaerobic digestion of a number of nitroaromatics has prompted development of a procedure for the production of spores of Clostridium bifermentans, and a medium for their effective production has been developed (Sembries and Crawford 1997). 

A narrow beam, attainable with Raman, was used by Schuster et al.4 to characterize the population distribution in Clostridium cultures. The technique was applied to the acetone-butanol (ABE) fermentation process in which the solventogenic Clostridia go through a complex cell cycle. After drying the cells on calcium fluoride carriers, single-cell spectra were obtained. Cells of different morphology showed different spectra. A number of cell components could be detected and varied in quantity. The approach was seen to be far faster than conventional methods. 

Hatheway, C.L., Clostridium botulinum and other Clostridia that produce botulinum neurotoxin, in Hauschild, A.H.W. and Dodds, K.L,. eds., Clostridium botulinum Ecology and Control in Foods, Marcel Dekker, New York, pp. 3-20, 1993. 

Gas gangrene Clostridium perfringens Clostridia toxin Activates phosphohpase to break down cell membranes. (Major cause of death in First World War and American Civil War)... 

Treatment with antibacterial agents alters the normal flora of the colon and may permit overgrowth of Clostridia. Studies indicate that a toxin produced by Clostridium difficile is a primary cause of antibiotic-associated colitis. ... 

A characteristic cultural reaction of Clostridium perfringens anJ many other Clostridia is known as a stormy fermentation. When the organism is inoculated into milk the lactose is fermented and the casein is coagulated. 

Fig. 5.21. The end-products (circled) of microbial fermentations of pyruvate. Letters indicate the organisms able to perform these reactions. (/<) Lactic acid bacteria (Streptococcus, Lactobacillus) (B) Clostridium propionicum (C) Yeast, Zymomonas mobilis, Sarcina ventriculr, (D) Enterobacteriaceae (Coli-aerogenes) (E) Clostridia, ...

Acrylate and 3-MPA were readily metabolised by sediment microbes when they were present at micromolar concentrations but were not so easily degraded at millimolar levels. Acrylate is metabolised by a variety of bacteria. Escherichia coli converts acrylyl-CoA to pyruvate via lactyl-CoA, and some clostridia ferment acrylate, via CoA intermediates, to a mixture of acetate and propionate. Of particular relevance to the fate of DMSP was the isolation by Wagner and Stadtman (14) of a species of Clostridium (probably . propionicuml from river mud that fermented DMSP as follows ... 

Species of Clostridium have been used on a very large scale for the production of industrial solvents such as acetone and butanol. Many clostridia ferment sugars with the formation of carbon dioxide, hydrogen and butyric acid. Some of them convert butyric acid to butanol and the acetic acid to ethanol and acetone. The acetone-butanol process by Clostridium acetobutylicum expanded after its introduction just before World War I. Although the industry has now been almost totally replaced by the synthetic production from oil, it may again be of interest for the production of renewable monomers. 

The method has been used for semi-quantitative monitoring of the changes in the protein patterns in Clostridium acetobutylicum [10]. Recently, it has been further assessed for linearity and other analytical features and extended in application to discriminate between different physiological states (acid production versus solvent production) in solventogenic Clostridia [71,72]) (Fig. 4). 

Table 3 shows the recovery and extent of enrichment in each of the various purification steps of ferredoxin from Clostridium acidi-urici by using DEAE-cellulose and ammonium sulfate fractionation (Buchanan, Lovenberg, and Rabinowitz (32)). This procedure yields crystalline preparations from all clostridia which have been tested. Various modifications are employed for the crystallization of ferredoxin from other bacteria (Figs. 1 and 2). 

---