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The tetrachloroethene (PCE)-respiring bacterium Sulfurospirillum multivorans produces a unique cobamide, namely, norpseudo-B 12 , which, in comparison to other cobamides, e.g., cobalamin and pseudo-B 12 , lacks the methyl group in the linker moiety of the nucleotide loop. In this study, the protein SMUL_1544 was shown to be responsible for the formation of the unusual linker moiety, which is most probably derived from ethanolamine-phosphate (EA-P) as the precursor. The product of the SMUL_1544 gene successfully complemented a Salmonella enterica ⌬cobD mutant. The cobD gene encodes an L-threonine-O-3-phosphate (L-Thr-P) decarboxylase responsible for the synthesis of (R)-1-aminopropan-2-ol O-2-phosphate (AP-P), required specifically for cobamide biosynthesis. When SMUL_1544 was produced in the heterologous host lacking CobD, norpseudo-B 12 was formed, which pointed toward the formation of EA-P rather than AP-P. Guided cobamide biosynthesis experiments with minimal medium supplemented with L-Thr-P supported cobamide biosynthesis in S. enterica producing SMUL_1544 or S. multivorans. Under these conditions, both microorganisms synthesized pseudo-B 12 . This observation indicated a flexibility in the SMUL_1544 substrate spectrum.

Molecular shape and pharmacological function are interconnected. To capture shape, the fractal dimensionality concept was employed, providing a natural similarity measure for the virtual screening of de novo generated small molecules mimicking the structurally complex natural product (−)‐englerin A. Two of the top‐ranking designs were synthesized and tested for their ability to modulate transient receptor potential (TRP) cation channels which are cellular targets of (−)‐englerin A. Intracellular calcium assays and electrophysiological whole‐cell measurements of TRPC4 and TRPM8 channels revealed potent inhibitory effects of one of the computer‐generated compounds. Four derivatives of this identified hit compound had comparable effects on TRPC4 and TRPM8. The results of this study corroborate the use of fractal dimensionality as an innovative shape‐based molecular representation for molecular scaffold‐hopping.

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