Correction: Mudie et al. In Vitro-In Silico Tools for Streamlined Development of Acalabrutinib Amorphous Solid Dispersion Tablets. Pharmaceutics 2021, 13, 1257

The authors wish to make the following corrections to this paper [...]

Synthesis of Ferulenol by Engineered Escherichia coli: Structural Elucidation by Using the In Silico Tools

4-Hydroxycoumarin (4HC) has been used as a lead compound for the chemical synthesis of various bioactive substances and drugs. Its prenylated derivatives exhibit potent antibacterial, antitubercular, anticoagulant, and anti-cancer activities. In doing this, E. coli BL21(DE3)pLysS strain was engineered as the in vivo prenylation system to produce the farnesyl derivatives of 4HC by coexpressing the genes encoding Aspergillus terreus aromatic prenyltransferase (AtaPT) and truncated 1-deoxy-D-xylose 5-phosphate synthase of Croton stellatopilosus (CstDXS), where 4HC was the fed precursor. Based on the high-resolution LC-ESI(±)-QTOF-MS/MS with the use of in silico tools (e.g., MetFrag, SIRIUS (version 4.8.2), CSI:FingerID, and CANOPUS), the first major prenylated product (named compound-1) was detected and ultimately elucidated as ferulenol, in which information concerning the correct molecular formula, chemical structure, substructures, and classifications were obtained. The prenylated product (named compound-2) was also detected as the minor product, where this structure proposed to be the isomeric structure of ferulenol formed via the tautomerization. Note that both products were secreted into the culture medium of the recombinant E. coli and could be produced without the external supply of prenyl precursors. The results suggested the potential use of this engineered pathway for synthesizing the farnesylated-4HC derivatives, especially ferulenol.

Cheonggukjang-Specific Component 1,3-Diphenyl-2-propanone as A Novel PPARα/γ Dual Agonist: An In Vitro and In Silico Study

Background: Cheonggukjang is a traditional fermented soybean paste that is mostly consumed in Korea. However, the biological activities of Cheonggukjang specific compounds have not been studied. Thus, we aimed to discover a novel dual agonist for PPARα/γ from dietary sources such as Cheonggukjang specific volatile compounds and explore the potential role of PPARα/γ dual agonists using in vitro and in silico tools. Methods: A total of 35 compounds were selected from non-fermented and fermented soybean products cultured with Bacillus subtilis, namely Cheonggukjang, for analysis by in vitro and in silico studies. Results: Molecular docking results showed that 1,3-diphenyl-2-propanone (DPP) had the lowest docking score for activating PPARα (1K7L) and PPARγ (3DZY) with non-toxic effects. Moreover, DPP significantly increased the transcriptional activities of both PPARα and PPARγ and highly activated its expression in Ac2F liver cells, in vitro. Here, we demonstrated for the first time that DPP can act as a dual agonist of PPARα/γ using in vitro and in silico tools. Conclusions: The Cheonggukjang-specific compound DPP could be a novel PPARα/γ dual agonist and it is warranted to determine the therapeutic potential of PPARα/γ activation by dietary intervention and/or supplementation in the treatment of metabolic disorders without causing any adverse effects.

A New Validation Methodology for In Silico Tools Based on X-ray Computed Tomography Images of Tablets and a Performance Analysis of One Tool

In silico tools which predict the dissolution of pharmaceutical dosage forms using virtual matrices can be validated with virtual matrices based on X-ray micro-computed tomography images of real pharmaceutical formulations. Final processed images of 3 different tablet batches were used to check the performance of the in silico tool F-CAD. The goal of this work was to prove the performance of the software by comparing the predicted dissolution profiles to the experimental ones and to check the feasibility and application of the validation concept for in silico tools. Both virtual matrices based on X-ray micro-computed tomography images and designed by the software itself were used. The resulting dissolution curves were compared regarding their similarity to the experimental curve. The kinetics were analysed with the Higuchi and Korsmeyers–Peppas plot. The whole validation concept as such was feasible and worked well. It was possible to identify prediction errors of the software F-CAD and issues with the virtual tablets designed within the software.

Mutation of c.244G>T in NR5A1 gene causing 46, XY DSD by affecting RNA splicing

Objective To identify the pathogenic mechanism of the c.244G>T mutation in NR5A1 gene found in a Chinese patient with 46, XY disorders of sex development (DSD). Subjects and methods: Genomic DNA was extracted from a Chinese 46, XY DSD patient. Targeted next-generation and Sanger sequencing were performed to investigate and validate the gene mutation causing 46, XY DSD, respectively. In silico tools were used to predict the pathogenicity of the variant. Dual luciferase reporter gene assay and minigene splicing reporter assay were used to identify the pathogenicity of the variant. Results A novel heterozygous variant, c.244G>T (p.Ala82Ser), in NR5A1 gene was detected in the 46, XY DSD patient. Four of five silico tools predicting pathogenicity of missense variants indicated that the variant was pathogenic. However, in vitro functional study showed that p.Ala82Ser did not affect the transcriptional activity of NR5A1. In silico tools predicting the potential splicing loci revealed that c.244G>T led to aberrant splicing of NR5A1 RNA. Minigene splicing reporter assay confirmed that c.244G>T resulted in the deletion of exon2 or deletion of 19 nucleotides in 3′ end of exon2. Conclusions Mutation of c.244G>T in NR5A1 results in 46, XY DSD by inducing abnormal splicing of NR5A1 RNA instead of amino acid substitution of NR5A1.