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C30H28O4, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 9.473(14) Å, b = 9.775(14) Å, c = 14.43(2) Å, α = 100.354(17)°, β = 91.053(17)°, γ = 94.062(17)°, V = 1310(1) Å3, Z = 2, R gt(F) = 0.0517, wR ref(F 2) = 0.1803, T = 296(2) K.

C26H28N2O6, monoclinic, P21/c (no. 14), a = 15.962(9) Å, b = 14.828(8) Å, c = 9.929(5) Å, β = 93.303°, V = 2346(2) Å3, Z = 4, R gt(F) = 0.0515, wR ref(F 2) = 0.1621, T = 296(2) K.

Abstract The ribosomally synthesized and post-translationally modified peptide (RiPPs) class of natural products has undergone significant expansion due to the rapid growth in genome sequencing data. Using a bioinformatics approach, we identify the dehydrazoles, a novel class of hypermodified RiPPs that contain both side chain dehydration of Ser residues, and backbone heterocyclization at Ser, Thr, and Cys residues to the corresponding azol(in)es. Structure elucidation of the hypermodified peptide carnazolamide, a representative class member, shows that 18 post-translational modifications are installed by just five enzymes. Complete biosynthetic reconstitution demonstrates that dehydration is carried out by an unusual DUF4135 dehydration domain fused to a zinc-independent cyclase domain (CcaM). We demonstrate that CcaM only modifies Ser residues that precede an azole in the core peptide. As heterocyclization removes the carbonyl following the Ser residue, CcaM likely catalyzes dehydration without generating an enolate intermediate. Additionally, CcaM does not require the leader peptide, and this core-dependence effectively sets the order for the biosynthetic reactions. Biophysical studies demonstrate direct binding of azoles to CcaM consistent with this azole moiety-dependent dehydration. Bioinformatic analysis reveals more than 50 related biosynthetic gene clusters that contain additional catalysts that may produce structurally diverse scaffolds.

C28H32O6, orthorhombic, Pnma (no. 62), a = 7.752(2) Å, b = 29.959(8) Å, c = 10.176(3) Å, V = 2363.5(11) Å3, Z = 4, R gt(F) = 0.1145, wR ref(F 2) = 0.1076, T = 296(2) K.

Allopurinol (ALP) attenuates oxidative stress and diabetic cardiomyopathy (DCM), but the mechanism is unclear. Activation of nuclear factor erythroid 2-related factor 2 (Nrf2) following the disassociation with its repressor Keap1 under oxidative stress can maintain inner redox homeostasis and attenuate DCM with concomitant attenuation of autophagy. We postulated that ALP treatment may activate Nrf2 to mitigate autophagy over-activation and consequently attenuate DCM. Streptozotocin-induced type 1 diabetic rats were untreated or treated with ALP (100 mg/kg/d) for 4 weeks and terminated after heart function measurements by echocardiography and pressure-volume conductance system. Cardiomyocyte H9C2 cells infected with Nrf2 siRNA or not were incubated with high glucose (HG, 25 mmol/L) concomitantly with ALP treatment. Cell viability, lactate dehydrogenase, 15-F2t-Isoprostane and superoxide dismutase (SOD) were measured with colorimetric enzyme-linked immunosorbent assays. ROS, apoptosis, was assessed by dihydroethidium staining and TUNEL, respectively. The Western blot and qRT-PCR were used to assess protein and mRNA variations. Diabetic rats showed significant reductions in heart rate (HR), left ventricular eject fraction (LVEF), stroke work (SW) and cardiac output (CO), left ventricular end-systolic volume (LVVs) as compared to non-diabetic control and ALP improved or normalized HR, LVEF, SW, CO and LVVs in diabetic rats (all P

Objective To fabricate caffeic acid-grafted gelatin (CA-gel) hydrogels and investigate effects of the grafting ratios on the physicochemical properties of the hydrogels, and evaluate the antioxidant function of hydrogels. Methods CA-gel gelatin was synthesized by controlling the ratio of caffeic acid and gelatin, and the hydrogels were formed with laccase as the cross-linking agent. The molecular structure of caffeic acid-grafted gelatin was characterized by HPLC and 1H-NMR. The grafting degree of caffeic acid was determined by UV-Vis spectrophotometer and the gelation time of hydrogel was determined by vial-tilting method. The elastic modulus was measured by microsphere indentation method. The swelling ratio and degradation rate of the hydrogel were calculated according to mass change before and after swelling and degradation, and the scavenging effect on DPPH radical(DPPH·) was determined by the change of absorbance of DPPH radical solution. Cell counting kit-8 was used to evaluate the cytotoxicity of the hydrogels and the protective effect on fibroblasts in high oxidative stress microenvironment. Results Caffeic acid was grafted onto gelatin molecules with following respective parameters: grafting degrees were 33.0 μmol/g, 61.8 μmol/g and 74.4 μmol/g, the gelation time was 33 min, 42 min and 47 min, the swelling ratios of the hydrogels were 896.5%, 835.3% and 803.9%, the elastic modulus of the hydrogels were 7.2 kPa, 29.4 kPa and 34.5 kPa, and the scavenging effects on DPPH radical of the hydrogels were 38.5%, 41.9% and 49.8%, respectively. In addition, the degradation rate decreased with the increase of grafting degree. The hydrogels were non-cytotoxic and displayed protective effect on the fibroblasts in the peroxide-existing environment. Conclusions CA-gel hydrogels have adjustable gelation time, biodegradation rate, elastic modulus and free radical scavenging activity and show a significant protective effect against fibroblasts in high oxidative stress microenvironment as well.

Aiming at the requirements of data storage and sharing between side devices and among marketing distribution dispatching systems in cloud master station platform of power Internet of Things,a power data storage and sharing method based on blockchain and data lake is proposed. Firstly,the distributed power data storage architecture on edge layer is designed. Through ring signature and CryptoNote protocol,the data interaction between side device storage nodes is encrypted to realize the identity authentication of both parties,and the data sharing between nodes in power data security storage system is realized based on intelligent contract of blockchain. Then,the data sharing and access control model between the operation and dispatching platforms is constructed based on the data lake and the smart contract,in which the hash value of the data is stored in the blockchain,and the data is stored in the data lake,so as to realize the cross platform and cross domain secure sharing and access of data. Finally,an experimental platform is built to demonstrate the proposed method. The results show that the maximum storage delay time of the proposed method is short,and the throughput and security are also high,so it has a good application prospect.