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Erythropoietin (EPO) is a glycoprotein hormone that has been used to treat anemia in patients with chronic kidney disease and in cancer patients who are receiving chemotherapy. Here, we investigated the accessibility of the glutamine (Gln, Q) residues of recombinant human erythropoietin (rHuEPO) towards a thermoresistant variant microbial transglutaminase (mTGase), TG16 with the aim of developing novel rHuEPO conjugates that may potentially enhance its biological efficacy. As a model bioconjugation, we studied the reactivity of rHuEPO towards TG16 with a low molar mass amine group containing substrate, monodansyl cadaverine (MDC). The reactions were carried out at a Tm of 54.3 °C, the transition temperature of rHuEPO. Characterization by SDS-PAGE and mass spectrometry confirmed the conjugates formation. Then, we examined the conjugation of rHuEPO with a biodegradable and biocompatible polyester, poly(D-sorbitol adipate) (PDSA). To achieve this, PDSA was enzymatically synthesized using lipase B from Candida antartica (CAL-B), chemically modified with side chains having free primary amine (NH2) groups that can be acyl acceptor substrate of TG16, thoroughly characterized by 1H NMR spectroscopy, and then applied for the TG16-mediated conjugation reaction with rHuEPO. rHuEPO conjugates generated by this approach were identified by SDS-PAGE proving that the amine-grafted PDSA is accepted as a substrate for TG16. The successful conjugation was further verified by the detection of high molar mass fluorescent bands after labelling of amine-grafted PDSA with rhodamine B-isothiocyanate. Overall, this enzymatic procedure is considered as an effective approach to prepare biodegradable rHuEPO-polymer conjugates even in the presence of N- and O-glycans.

TaSnS2 single crystal and polycrystalline samples are investigated in detail by magnetization, electrical resistivity, and specific heat as well as Raman spectroscopy and nuclear magnetic resonance (NMR). Studies are focused on the temperature and magnetic field dependence of the superconducting state. We determine the critical fields for both directions B∥c and B⊥c. Additionally, we investigate the dependence of the resistivity, the critical temperature, and the structure through Raman spectroscopy under high pressure up to 10 GPa. At a pressure of ≈3GPa the superconductivity is suppressed below our minimum temperature. The Sn NMR powder spectrum shows a single line which is expected for the TaSnS2 phase and confirms the high sample quality. Pronounced de Haas-van Alphen oscillations in the ac susceptibility of polycrystalline sample reveal two pairs of frequencies indicating coexisting small and large Fermi surfaces. The effective mass of the smaller Fermi surface is ≈0.5me. We compare these results with the band structures from DFT calculations. Our findings on TaSnS2 are discussed in terms of a quasi-two-dimensional BCS superconductivity.

Common guava (Psidium guajava L.) is valued for its fruit, which is a source of vitamins, minerals, and natural antioxidants. However, guava production faces salinity challenges globally. Salinity through sodium chloride (NaCl) – 0 mM (control), 10/20 mM (low), 20/40 mM (medium), and 40/80 mM (high) – supplied through a standard Hoagland nutrient solution to 10 genetically diverse guava accessions from Kenya was investigated. Leaf number and dry matter (DM) were significantly reduced at the medium and high salinity levels while root DM remained similar. Root water content increased with rising salinity levels, whereas leaf water content was significantly reduced at the high NaCl level. A decrease in the leaf potassium/sodium (K/Na) and calcium/sodium (Ca/Na) ratios with increasing salinity was observed, possibly due to the high accumulation of Na rather than to the replacement of K and Ca. Leaf phosphorus (P) and sulphur (S) decreased with increasing salinity. Leaf boron (B) and iron (Fe) were significantly reduced only at the high salinity level. Differences among the accessions relative to the accumulation of Na were observed and positively correlated with the DM. Thus, the ability to maintain more DM under salt stress could serve as an indicator for salinity tolerance in Kenyan guava.

Common guava (Psidium guajava L.) is valued for its fruit, which is a source of vitamins, minerals, and natural antioxidants. However, guava production faces salinity challenges globally. Salinity through sodium chloride (NaCl) – 0 mM (control), 10/20 mM (low), 20/40 mM (medium), and 40/80 mM (high) – supplied through a standard Hoagland nutrient solution to 10 genetically diverse guava accessions from Kenya was investigated. Leaf number and dry matter (DM) were significantly reduced at the medium and high salinity levels while root DM remained similar. Root water content increased with rising salinity levels, whereas leaf water content was significantly reduced at the high NaCl level. A decrease in the leaf potassium/sodium (K/Na) and calcium/sodium (Ca/Na) ratios with increasing salinity was observed, possibly due to the high accumulation of Na rather than to the replacement of K and Ca. Leaf phosphorus (P) and sulphur (S) decreased with increasing salinity. Leaf boron (B) and iron (Fe) were significantly reduced only at the high salinity level. Differences among the accessions relative to the accumulation of Na were observed and positively correlated with the DM. Thus, the ability to maintain more DM under salt stress could serve as an indicator for salinity tolerance in Kenyan guava.