Metabolic diversity and responses of anteater clostridial isolates to chitin-based substrates

Ahmad Amin Nikol Modrackova Vaclav Tejnecky Vera Neuzil Bunesova ^*

• Czech University of Life Sciences Prague, Prague, Czechia

Aims: Clostridium species such as Clostridium perfringens, C. baratii, C. colicanis, Paraclostridium bifermentans, and Paeniclostridium sordellii, are Ggram-positive anaerobic endospore formers with diverse pathogenic mechanisms. Despite that are commensals of the gut of variable animal species, e.g. anteaters, less frequently of humans. The diet of anteaters, in which chitin and formic acid play an important role, is very specific, as well as clostridial metabolism.This study investigates the metabolic diversity and responses of anteater clostridial isolates to various substrates, namely chitin, chitosan, cellulose, N-acetyl-D-glucosamine (NAG), and glucose. All tested clostridia were able to grow in presence of chitin, cellulose, NAG, and glucose, but varied in metabolite production. However, presence of chitosan surprisingly showed the antimicrobial effect against clostridia, especially Pae. sordellii, P. bifermentans, and C. colicanis.Results demonstrate significant variations in fermentation profiles, and metabolite production across substrates and clostridial species. Acetate production was detected as common for all tested clostridia despite species variability and incoming substrates, as well as lactate, butyrate, propionate, and formate for some strains.In relation to digestion, anteater clostridia could play an important role in chitin and its degradation products, which, in the end, can influence clostridial occurrence and pathogenicity via chitosan.