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Biology subjects

von Erlach, T.

Publications and source records attributed to von Erlach, T..

2 recordsLinked to original sources

Tuning Histone Site Selectivity in the Nucleosome with Organometallic Agents

Platinum anticancer drugs tend to target DNA whereas certain ruthenium and osmium organometallic compounds, including those with known anticancer activity, preferentially bind histone proteins in chromatin. We earlier found that Ru/Os arene 2-pyridinecarbothioamide antitumor agents display unique or partially overlapping profiles of histone protein binding in the nucleosome compared to Ru arene phosphaadamantane (RAPTA) antimetastasis drugs, but the basis for this difference is unclear. Here we structurally characterized the nucleosome binding effects of arene ligand substitutions and carried out a multiscale simulation analysis, which reveals that the interplay between metal cation and non-leaving ligand identity dictates adduct stability and whether complexes target electronegative surface patches, internal crevices, or both. We show that the nucleosome superhelical crevice acts as a small molecule selectivity filter and that multi-site binding profiles can be expanded or reduced through defined ligand substitutions, which modulate dynamic and steric attributes. Our findings suggest new avenues for rationally developing Ru/Os organometallics that could help expand the scope of chromatin-targeting therapeutics. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/688318v2_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@188bc1dorg.highwire.dtl.DTLVardef@1f619d5org.highwire.dtl.DTLVardef@1a0ebaorg.highwire.dtl.DTLVardef@bd0abb_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

Computationally guided high-throughput design of self-assembling drug nanoparticles

Nanoformulations are transforming our capacity to effectively deliver and treat a myriad of conditions. However, many nanoformulation approaches still suffer from high production complexity and low drug loading. One potential solution relies on harnessing co-assembly of drugs and small molecular excipients to facilitate nanoparticle formation through solvent exchange without the need for chemical synthesis, generating nanoparticles with up to 95% drug loading. However, there is currently no understanding which of the millions of possible combinations of small molecules can result in the formation of these nanoparticles. Here we report the development of a high-throughput screening platform coupled to machine learning to enable the rapid evaluation of such nanoformulations. Our platform identified 101 novel self-assembling drug nanoparticles from 2.1 million pairings derived from 788 candidate drugs with one of 2686 excipients, spanning treatments for multiple diseases and often harnessing well-known food additives, vitamins, or approved drugs as carrier materials - with potential for accelerated approval and translation. Given their long-term stability and potential for clinical impact, we further characterize novel sorafenib-glycyrrhizin and terbinafine-taurocholic acid nanoparticles ex vivo and in vivo. We anticipate that this platform could accelerate the development of safer and more efficacious nanoformulations with high drug loadings for a wide range of therapeutics.

bioengineering↗