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The FEBS journal 290(3), 821 - 836 (2022). doi:10.1111/febs.16616, Human histone deacetylase 6 (HDAC6) is a structurally unique, multido-main protein implicated in a variety of physiological processes includingcytoskeletal remodelling and the maintenance of cellular homeostasis. Ourcurrent understanding of the HDAC6 structure is limited to isolateddomains, and a holistic picture of the full-length protein structure, includ-ing possible domain interactions, is missing. Here, we used an integrativestructural biology approach to build a solution model of HDAC6 by com-bining experimental data from several orthogonal biophysical techniquescomplemented by molecular modelling. We show that HDAC6 is bestdescribed as a mosaic of folded and intrinsically disordered domains thatin-solution adopts an ensemble of conformations without any stable inter-actions between structured domains. Furthermore, HDAC6 forms dimers/higher oligomers in a concentration-dependent manner, and its oligomer-ization is mediated via the positively charged N-terminal microtubule-binding domain. Our findings provide the first insights into the structure offull-length human HDAC6 and can be used as a basis for further researchinto structure function and physiological studies of this unique deacetylase., Published by Wiley-Blackwell, Oxford [u.a.]

Chemical science 13(39), 11680 - 11695 (2022). doi:10.1039/D2SC02794A, Over half the proteins in the E. coli cytoplasm form homo or hetero-oligomeric structures. Experimentally determined structures are often considered in determining a protein's oligomeric state, but static structures miss the dynamic equilibrium between different quaternary forms. The problem is exacerbated in homo-oligomers, where the oligomeric states are challenging to characterize. Here, we re-evaluated the oligomeric state of 17 different bacterial proteins across a broad range of protein concentrations and solutions by native mass spectrometry (MS), mass photometry (MP), size exclusion chromatography (SEC), and small-angle X-ray scattering (SAXS), finding that most exhibit several oligomeric states. Surprisingly, some proteins did not show mass-action driven equilibrium between the oligomeric states. For approximately half the proteins, the predicted oligomeric forms described in publicly available databases underestimated the complexity of protein quaternary structures in solution. Conversely, AlphaFold multimer provided an accurate description of the potential multimeric states for most proteins, suggesting that it could help resolve uncertainties on the solution state of many proteins., Published by RSC, Cambridge

Nanomaterials 12(6), 893 - (2022). doi:10.3390/nano12060893, Phenylketonuria (PKU) is an autosomal recessive disease caused by deficient activity of human phenylalanine hydroxylase (hPAH), which can lead to neurologic impairments in untreated patients. Although some therapies are already available for PKU, these are not without drawbacks. Enzyme-replacement therapy through the delivery of functional hPAH could be a promising strategy. In this work, biophysical methods were used to evaluate the potential of [N1112(OH)][C4F9SO3], a biocompatible fluorinated ionic liquid (FIL), as a delivery system of hPAH. The results herein presented show that [N1112(OH)][C4F9SO3] spontaneously forms micelles in a solution that can encapsulate hPAH. This FIL has no significant effect on the secondary structure of hPAH and is able to increase its enzymatic activity, despite the negative impact on protein thermostability. The influence of [N1112(OH)][C4F9SO3] on the complex oligomerization equilibrium of hPAH was also assessed., Published by MDPI, Basel