We identified Streptomyces globisporus bja209 through a targeted screen of actinomycetes from natural habitats using an E. coli JW5503 ΔtolC DualRep2(c) reporter strain. This strain produced antibacterial compounds whose action depended on the growth medium. HPLC-MS and genomic analysis revealed two metabolites: albomycin δ2 (a translation inhibitor) and desferrioxamine E. The latter induced the SOS response. Desferrioxamine E exhibited a narrow spectrum of antagonistic activity against carbapenem-resistant A. baumannii and C. michiganensis, and its production was critically regulated by iron concentration. Notably, the structurally similar desferrioxamine B was inactive. Contrary to previous reports, pangenome analysis of published GenBank genomes revealed that albomycin BGC is restricted to specific S. globisporus strains and not present in other Streptomycetes phylogenetic clades. The C-1027 BGC was found in a large linear plasmid (165.5 kb) of the S. globisporus bja209 strain and also found exclusively on linear plasmids in some of the published S. globisporus genomes.

Background: Gluten-related disorders, particularly celiac disease, are triggered in susceptible individuals by the toxic effects of gluten, the major storage protein of wheat grains. This toxicity can be reduced by wheat glutenases. Members of the papain-like cysteine protease family, which can act in the human gastrointestinal tract, are promising candidates for the enzymatic treatment of celiac disease. Methods: Two wheat proteases were selected using AlphaFold2, produced in recombinant forms, and characterized. Their glutenase potentials under acidic or slightly acidic conditions were evaluated and compared with the properties of the previously characterized wheat glutenase Triticain-α. Results: All enzymes tested, Ta-P7, Ta-V6, and Triticain-α, were able to hydrolyze the model substrate (α-gliadin-derived epitope) in the pH range of 3.6–7.5. Nevertheless, Triticain-α performs the most efficient hydrolysis of the peptide substrate under the conditions of the gastrointestinal tract, according to its kinetic characteristics. In the wheat gluten degradation experiment at pH 4.6 and 37 °C, both Ta-P7 and Triticain-α cleaved the mixture almost completely within 5 min. In addition, Triticain-α and Ta-P7 significantly reduced the levels of toxic peptides compared to both intact gluten and gluten treated with pepsin-trypsin digestion as tested by the Ridascreen Gliadin Kit. Conclusions: Novel wheat proteases under investigation possess the expected glutenase activity to varying degrees; however, Triticain-α is a primary candidate for potential use in the enzymatic therapy of gluten-related disorders.