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Abstract: Efficient use of energy for cooling applications is a very important and challenging field in science. Ultra-low temperature actuated (Tdriving < 80 °C) adsorption-driven chillers (ADCs) with water as the cooling agent are one environmentally benign option. The nanoscale metal-organic framework [Al(OH)(C6H2O4S)] denoted CAU-23 was discovered that possess favorable properties, including water adsorption capacity of 0.37 gH2O/gsorbent around p/p0 = 0.3 and cycling stability of at least 5000 cycles. Most importantly the material has a driving temperature down to 60 °C, which allows for the exploitation of yet mostly unused temperature sources and a more efficient use of energy. These exceptional properties are due to its unique crystal structure, which was unequivocally elucidated by single crystal electron diffraction. Monte Carlo simulations were performed to reveal the water adsorption mechanism at the atomic level. With its green synthesis, CAU-23 is an ideal material to realize ultra-low temperature driven ADC devices.

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Abstract: Natural variation separates Epstein-Barr virus (EBV) into type 1 and type 2 strains. Type 2 EBV is less transforming in vitro due to sequence differences in the EBV transcription factor EBNA2. This correlates with reduced activation of the EBV oncogene LMP1 and some cell genes. Transcriptional activation by type 1 EBNA2 can be suppressed through the binding of two PXLXP motifs in its transactivation domain (TAD) to the dimeric coiled-coil MYND domain (CC-MYND) of the BS69 repressor protein (ZMYND11). We identified a third conserved PXLXP motif in type 2 EBNA2. We found that type 2 EBNA2 peptides containing this motif bound BS69CC-MYND efficiently and that the type 2 EBNA2TAD bound an additional BS69CC-MYND molecule. Full-length type 2 EBNA2 also bound BS69 more efficiently in pull-down assays. Molecular weight analysis and low-resolution structures obtained using small-angle X-ray scattering showed that three BS69CC-MYND dimers bound two molecules of type 2 EBNA2TAD, in line with the dimeric state of full-length EBNA2 in vivo. Importantly, mutation of the third BS69 binding motif in type 2 EBNA2 improved B-cell growth maintenance and the transcriptional activation of the LMP1 and CXCR7 genes. Our data indicate that increased association with BS69 restricts the function of type 2 EBNA2 as a transcriptional activator and driver of B cell growth and may contribute to reduced B-cell transformation by type 2 EBV.

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Abstract: The rational design of alternative antimicrobial materials with reduced toxicity toward mammalian cells is highly desired due to the growing occurrence of bacteria resistant to conventional antibiotics. A promising approach is the design of lipid‐based antimicrobial nanocarriers. However, most of the commonly used polymer‐stabilized nanocarriers are cytotoxic. Herein, the design of a novel, stabilizer‐free nanocarrier for the human cathelicidin derived antimicrobial peptide LL‐37 that is cytocompatible and promotes cell proliferation for improved wound healing is reported. The nanocarrier is formed through the spontaneous integration of LL‐37 into novel, stabilizer‐free glycerol mono‐oleate (GMO)‐based cubosomes. Transformations in the internal structure of the cubosomes from Pn3m to Im3m‐type and eventually their transition into small vesicles and spherical micelles are demonstrated upon the encapsulation of LL‐37 into their internal bicontinuous cubic structure using small angle X‐ray scattering, cryogenic transmission electron microscopy, and light scattering techniques. Additional in vitro biological assays show the antimicrobial activity of the stabilizer‐free nano‐objects on a variety of bacteria strains, their cytocompatibility, and cell‐proliferation enhancing effect. The results outline a promising strategy for the comprehensive design of antimicrobial, cytocompatible lipid nanocarriers for the protection and delivery of bioactive molecules with potential for application as advanced wound healing materials.

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Abstract: Many proteins are synthesized as precursors, with propeptides playing a variety of roles such as assisting in folding or preventing them from being active within the cell. While the precise role of the propeptide in fungal lipases is not completely understood, it was previously reported that mutations in the propeptide region of the Rhizomucor miehei lipase have an influence on the activity of the mature enzyme, stressing the importance of the amino acid composition of this region. We here report two structures of this enzyme in complex with its propeptide, which suggests that the latter plays a role in the correct maturation of the enzyme. Most importantly, we demonstrate that the propeptide shows inhibition of lipase activity in standard lipase assays and propose that an important role of the propeptide is to ensure that the enzyme is not active during its expression pathway in the original host.

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Abstract: The understanding of the gypsum (CaSO4∙2H2O) formation pathway from aqueous solutions has been the subject of intensive research in the last couple of years. This interest stems from the fact that gypsum appears to fall into a broader category of crystalline materials whose formation does not follow classical nucleation and growth theories. The pathways involve transitory precursor cluster species, yet the actual structural properties of such clusters are not very well understood. Here, we show how in situ high-energy X-ray diffraction (HEXD) experiments and molecular dynamics (MD) simulations can be combined to derive the structure of small CaSO4 clusters, which are precursors to crystalline gypsum. We fitted several plausible structures to the derived pair distribution functions (PDFs), and explored their dynamic properties using unbiased MD based on both rigid-ion and polarizable force-fields. Determination of the structure and (meta)stability of the primary species is important both from a fundamental and applied perspective; for example, this will allow for improved design of additives for greater control of the nucleation pathway.