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Kim, C.-Y.

Publications and source records attributed to Kim, C.-Y..

2 recordsLinked to original sources

An Equivariant Generative Framework for Molecular Graph-Structure Co-Design

Designing molecules with desirable physiochemical properties and functionalities is a long-standing challenge in chemistry, material science, and drug discovery. Recently, machine learning-based generative models have emerged as promising approaches for de novo molecule design. However, further refinement of methodology is highly desired as most existing methods lack unified modeling of 2D topology and 3D geometry information and fail to effectively learn the structure-property relationship for molecule design. Here we present MolCode, a roto-translation equivariant generative framework for Molecular graph-structure Co-design. In MolCode, 3D geometric information empowers the molecular 2D graph generation, which in turn helps guide the prediction of molecular 3D structure. Extensive experimental results show that MolCode outperforms previous methods on a series of challenging tasks including de novo molecule design, targeted molecule discovery, and structure-based drug design. Particularly, MolCode not only consistently generates valid (99.95% Validity) and diverse (98.75% Uniqueness) molecular graphs/structures with desirable properties, but also generate drug-like molecules with high affinity to target proteins (61.8% high affinity ratio), which demonstrates MolCodes potential applications in material design and drug discovery. Our extensive investigation reveals that the 2D topology and 3D geometry contain intrinsically complementary information in molecule design, and provides new insights into machine learning-based molecule representation and generation.

bioinformatics↗

Class II UvrA protein Ecm16 requires ATPase activity to render resistance against echinomycin

II.Bacteria use various strategies to become antibiotic resistant. The molecular details of these strategies are not fully understood. We can increase our understanding by investigating the same strategies found in antibiotic-producing bacteria. In this work, we characterize the self-resistance protein Ecm16 encoded by echinomycin-producing bacteria. Ecm16 is a structural homolog of the Nucleotide Excision Repair (NER) protein UvrA. Expression of ecm16 in the heterologous system Escherichia coli was sufficient to render resistance against echinomycin. Ecm16 preferentially binds double-stranded DNA over single-stranded DNA and is likely to primarily interact with the backbone of DNA using a nucleotide-independent binding mode. Ecm16s binding affinity for DNA increased significantly when the DNA is intercalated with echinomycin. Ecm16 can repair echinomycin-induced DNA damage independently of NER. Like UvrA, Ecm16 has ATPase activity and this activity is essential for Ecm16s ability to render echinomycin resistance. Notably, UvrA and Ecm16 were unable to complement each others function. Increasing the cellular levels of UvrA in E. coli was insufficient to render echinomycin resistance. Similarly, Ecm16 was unable to repair DNA damage that is specific to UvrA. Together, our findings identify new mechanistic details of how a refurbished DNA repair protein Ecm16 can specifically render resistance to the DNA intercalator echinomycin. Our results, together with past observations, suggest a model where Ecm16 recognizes double helix distortions caused by echinomycin and repairs the problem independently of NER.

microbiology↗