Non-pathogenic clostridia are exploited for a diverse range of applications. These include established use within the solvent manufacturing industry, as well as utility for food production and treating cancer. Using our proprietary CRISPR-Cas technology, CLEAVE™, to directly manipulate the clostridial genome, we aim to both enhance existing applications and facilitate further development opportunities.

How are clostridia used for solvent manufacturing?

Solvent-producing clostridia have been of interest to researchers for over 100 years, with the advent of WW1 driving the use of Clostridium acetobutylicum for acetone production via the Weizmann acetone–butanol–ethanol (ABE) fermentation process. This represented the first large-scale industrial fermentation process of global significance and paved the way toward using ABE-producing clostridia for other forms of solvent manufacturing. However, while clostridia have become established tools for the chemical and biofuel markets, the associated cost of feedstocks has presented an ongoing challenge for those engaged in developing more sustainable fermentation routes¹.

How are clostridia used in agricultural food production?

In addition to being exploited for the substances they naturally produce, clostridial strains are also used directly as dietary supplements within the food production industry. For example, Clostridium butyricum has been added to chicken feed to promote growth performance (for reduced production costs) and improve resistance to infectious diseases (as an alternative to using antibiotics), with studies showing it to be more tolerant of low pH compared with Lactobacillus and Bifidobacterium². Clostridium butyricum has also demonstrated encouraging results within pig and goat production, where it has improved weight gain and feed efficiency³.

How are clostridia used to treat cancer?

Strategies utilizing clostridia to treat cancer are largely focused on selective tumour targeting and destruction. Clostridia-based methods investigated for oncology include clostridium directed enzyme prodrug therapy (CDEPT), where genetically engineered clostridial species function to cleave a pro-drug into an active form; clostridium directed antibody therapy (CDAT), which involves clostridial production of anti-tumour antibodies; and combined bacteriolytic therapy (COBALT), where clostridia known to demonstrate direct anti-tumour effects are administered with other forms of cancer treatment⁴.

Why clostridia?

The non-pathogenic clostridial strains are anaerobic, giving them a major advantage for improving or establishing processes where this feature is essential. Examples include applications targeting environments that are inherently deficient in oxygen, such as the gut microbiome, tumour microenvironment, and soil, as well as processes like anaerobic digestion and waste treatment. Additionally, the fact that non-pathogenic clostridia don’t produce endotoxins provides further opportunities to explore diverse applications.

What is CLEAVE™ and how can it be used to expand the capabilities of clostridia?

CLEAVE™ is our patented technology based on the CRISPR-Cas system, which creates precise modifications in the clostridial genome to accelerate the production of recombinant strains. It is suitable for all modifications, including single nucleotide polymorphisms (SNPs), deletions, insertions, and promoter exchange. Importantly, by eliminating the need for secondary selection markers, CLEAVE™ minimizes screening requirements and ensures the resultant strains are completely free of un-desired plasmids and antibiotic resistance markers.

What’s in biocleave’s clostridial pipeline?

To date, we have used our technology for the scalable production of high-quality recombinant proteins. Our product portfolio includes the clostridial toxin light and heavy chains, terpene synthases, and several recombinant protozoal proteins implicated in neglected tropical diseases (NTDs). Other product classes currently under development include poly ADP-ribose polymerases (PARPs), neurite growth inhibitors, and various signalling peptides.

Recombinant protein expression is just the beginning for clostridia – there is so much more these exciting microbes can do and we are working on ways to harness this untapped potential. To learn more about our clostridium platform and how it could accelerate your research, contact us today!

References:

1. Poehlein A, Solano JDM, Flitsch SK, et al. Microbial solvent formation revisited by comparative genome analysis. Biotechnol Biofuels. 2017;10:58. Published 2017 Mar 9. https://doi.org/10.1186/s13068-017-0742-z
2. Li W. Xu B, Wang L, et al. Effects of Clostridium butyricum on Growth Performance, Gut Microbiota and Intestinal Barrier Function of Broilers, Front. Microbiol., 08 December 2021 https://doi.org/10.3389/fmicb.2021.777456
3. Cai L, Hartanto R, Zhang J, et al. Clostridium butyricum Improves Rumen Fermentation and Growth Performance of Heat-Stressed Goats In Vitro and In Vivo, Animals 2021, 11(11), 3261; https://doi.org/10.3390/ani11113261
4. Umer B, Good D, Anné J, et al. Clostridial spores for cancer therapy: targeting solid tumour microenvironment. J Toxicol. 2012; 2012:862764. doi: https://doi.org/10.1155/2012/862764