Bioconversions

Morris, Jonathan

doi:10.1007/978-1-4757-9718-3_6

Cited by 5 publications

(2 citation statements)

References 156 publications

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“…Some of these bacteria produce potent neurotoxins which are responsible for neurological diseases in humans and animals, like tetanus or botulism ( Böhnel et al, 2001 ; Johnson and Bradshaw, 2001 ). On the other hand, many clostridial strains are widely used in biotechnology for the production of organic solvents like acetone, ethanol, butanol ( Jang et al, 2012 ) or they occur also in methane producing anaerobic fermentation plants ( Morris, 1989 ). A common feature within the genus is the ability to form endospores during nutrient deficient conditions rendering them extremely resistant against many adverse environmental factors ( Andreesen et al, 1989 ).…”

Section: Introductionmentioning

confidence: 99%

Systemic colonization of clover (Trifolium repens) by Clostridium botulinum strain 2301

Zeiller

Rothballer

Iwobi³

et al. 2015

Front. Microbiol.

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In recent years, cases of botulism in cattle and other farm animals and also in farmers increased dramatically. It was proposed, that these cases could be affiliated with the spreading of compost or other organic manures contaminated with Clostridium botulinum spores on farm land. Thus, soils and fodder plants and finally farm animals could be contaminated. Therefore, the colonization behavior and interaction of the botulinum neurotoxin (BoNT D) producing C. botulinum strain 2301 and the non-toxin producing Clostridium sporogenes strain 1739 were investigated on clover (Trifolium repens) in a field experiment as well as in phytochamber experiments applying axenic and additionally soil based systems under controlled conditions. Plants were harvested and divided into root and shoot parts for further DNA isolation and polymerase chain reaction (PCR) assays; subsamples were fixed for fluorescence in situ hybridization analysis in combination with confocal laser scanning microscopy. In addition, we observed significant differences in the growth behavior of clover plants when inoculated with clostridial spores, indicating a plant growth promoting effect. Inoculated plants showed an increased growth index (shoot size, wet and dry weight) and an enlarged root system induced by the systemic colonization of clover by C. botulinum strain 2301. To target C. botulinum and C. sporogenes, 16S rDNA directed primers were used and to specifically detect C. botulinum, BoNT D toxin genes targeted primers, using a multiplex PCR approach, were applied. Our results demonstrate an effective colonization of roots and shoots of clover by C. botulinum strain 2301 and C. sporogenes strain 1739. Detailed analysis of colonization behavior showed that C. botulinum can occur as individual cells, in cell clusters and in microcolonies within the rhizosphere, lateral roots and within the roots tissue of clover.

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Section: Introductionmentioning

confidence: 99%

Systemic colonization of clover (Trifolium repens) by Clostridium botulinum strain 2301

Zeiller

Rothballer

Iwobi³

et al. 2015

Front. Microbiol.

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“…Proteolytic clostridia are found in many natural environments, and some species such as Clostridium sporogenes and C. bifermentans are of economic and biotechnological significance through their activities as food spoilage organisms (Schmidt 1966;Frazier and Westhoff 1978;Bergere and Accolas 1986) and as potential sources of commercially exploitable enzymes (Simon et al 1985;Morris 1989).…”

Section: Introductionmentioning

confidence: 99%

Physiological and nutritional determinants of protease secretion by Clostridium sporogenes: characterization of six extracellular proteases

Allison

Macfarlane

1992

Appl Microbiol Biotechnol

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Proteases were the principal secretory proteins of Clostridium sporogenes and were optimally produced after active growth at 37 ° C. Glucose, ammonia and peptides repressed protease production. Protease formation was maximal in cultures grown at pH 6.5, but proteolytic activity exhibited a pH optimum of 7.0-8.0. Protease activity in culture filtrates was stimulated by divalent metal ions (Ca 2÷, Mn 2÷ and Co 2÷) and was strongly inhibited by ethylene diaminetetraacetate (EDTA) and thimerosal. Non-denaturing polyacrylamide gel electrophoresis and H P L C gel filtration demonstrated the presence of six major proteases of low molecular mass (approx. 15-35 kDa). The enzymes were partially purified from non-denaturing gels. Each hydrolysed azocoll and azocasein, but differed in their activity against a range of native collagen substrates. All six enzymes degraded human placental collagen (Type IV) but only one had a broad substrate specificity, being able to hydrolyse the more recalcitrant collagens (Types I, II and III). Experiments with individual proteases showed that their activities were strongly inhibited (40-85%) by 5 mM EDTA, indicating t h a t they were metalloproteases. The enzymes exhibited different susceptibilities to inhibition by either 3 mM phenylmethylsulphonylfluoride (PMSF), 5 mM thimerosal, or 10 mM cysteine, which respectively inhibit serine, thiol and metalloproteases.

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