Genotype-environment interaction (GxE) is a common phenomenon in sorghum. The effect of GxE can be reduced by identifying stable genotypes across environments. An investigation was conducted to study ...yield stability and adaptability of 13 sorghum genotypes across six environments. Additive Main-effect and Multiplicative Interaction (AMMI), Genotype and Genotype-Environment interaction (GGE), and stability analyses were computed. The AMMI analysis explained 68.67% of the GxE variance, while GGE captured 74.41% of the GGE variance. GGE analysis identified Kobo (KB13 and KB14) as a suitable environment for selecting generally adapted lowland sorghum genotypes. The GGE and the stability analyses further identified G13 and G2 as the least and the most desirable sorghum genotypes, respectively. Genotype G2 has high level of adaptability to the northeastern parts of Ethiopia, as evidenced by its high-yielding ability, stability and early maturity. This genotype (G2; WSV-387 x E-36-2) was released with the approval of the National Variety Release Committee in 2017. Need-based large volume seed production, dissemination over a wider area and the consequent adoption of the variety by target farmers would be convenient and fast.
The deuteration of proteins and selective labeling of side chain methyl groups has greatly enhanced the molecular weight range of proteins and protein complexes which can be studied using solution ...NMR spectroscopy. Protocols for the selective labeling of all six methyl group containing amino acids individually are available, however to date, only a maximum of five amino acids have been labeled simultaneously. Here, we describe a new methodology for the simultaneous, selective labeling of all six methyl containing amino acids using the 115 kDa homohexameric enzyme CoaD from
E. coli
as a model system. The utility of the labeling protocol is demonstrated by efficiently and unambiguously assigning all methyl groups in the enzymatic active site using a single 4D
13
C-resolved HMQC–NOESY–HMQC experiment, in conjunction with a crystal structure. Furthermore, the six fold labeled protein was employed to characterize the interaction between the substrate analogue (R)-pantetheine and CoaD by chemical shift perturbations, demonstrating the benefit of the increased probe density.
Prevalence of type II diabetes mellitus(T2DM) is substantially increasing in Ethiopia but there are no studies on its drug therapy. To assess drug therapy for T2DM and check association between ...fasting blood glucose levels with patient demographics, clinical characteristics and medications. A cross-sectional institution based study was conducted on T2DM patients over a 1 month period using patient chart review and key informant interview at the diabetes clinic of Tikur Anbessa Specialized Hospital (TASH). Of 103 patients enrolled females accounted 59.2%. The mean age was 52.2 years and 96.12% of patients were from Addis Ababa. The mean fasting blood glucose (FBG) and body mass index (BMI) were 155.99 mg/dl and 26.4 kg/m^sup 2^ respectively. About 51.45% of the patients were overweight; and neutral protamine hagedorn insuline (NPH) (56.3%), metformin plus glibenclamide (19.4%) and metformin (10.7%) were the most common drug therapies. But there was no significant association of FBG levels of patients with either, gender, age, BMI or medications. The drug therapy at the diabetes clinic was in line with recommendations of International Diabetes Federation (IDF)despite lack of uniform guideline.
Direct pharmacological inhibition of RAS has remained elusive, and efforts to target CRAF have been challenging due to the complex nature of RAF signaling, downstream of activated RAS, and the poor ...overall kinase selectivity of putative RAF inhibitors. Herein, we describe 15 (LXH254, Aversa, R.; et al. Int. Patent WO2014151616A1, 2014), a selective B/C RAF inhibitor, which was developed by focusing on drug-like properties and selectivity. Our previous tool compound, 3 (RAF709; Nishiguchi, G. A.; et al. J. Med. Chem. 2017, 60, 4969), was potent, selective, efficacious, and well tolerated in preclinical models, but the high human intrinsic clearance precluded further development and prompted further investigation of close analogues. A structure-based approach led to a pyridine series with an alcohol side chain that could interact with the DFG loop and significantly improved cell potency. Further mitigation of human intrinsic clearance and time-dependent inhibition led to the discovery of 15. Due to its excellent properties, it was progressed through toxicology studies and is being tested in phase 1 clinical trials.
ATR, a protein kinase in the PIKK family, plays a critical role in the cell DNA-damage response and is an attractive anticancer drug target. Several potent and selective inhibitors of ATR have been ...reported showing significant antitumor efficacy, with most advanced ones entering clinical trials. However, due to the absence of an experimental ATR structure, the determinants contributing to ATR inhibitors' potency and specificity are not well understood. Here we present the mutations in the ATP-binding site of PI3Kα to progressively transform the pocket to mimic that of ATR. The generated PI3Kα mutants exhibit significantly improved affinity for selective ATR inhibitors in multiple chemical classes. Furthermore, we obtained the X-ray structures of the PI3Kα mutants in complex with the ATR inhibitors. The crystal structures together with the analysis on the inhibitor affinity profile elucidate the roles of individual amino acid residues in the binding of ATR inhibitors, offering key insights for the binding mechanism and revealing the structure features important for the specificity of ATR inhibitors. The ability to obtain structural and binding data for these PI3Kα mutants, together with their ATR-like inhibitor binding profiles, makes these chimeric PI3Kα proteins valuable model systems for structure-based inhibitor design.
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•ATR is an attractive anticancer drug target but no X-ray structure is available.•Designed PI3Kα mutants to transform the ATP-binding site to mimic that of ATR.•Resulting PI3Kα mutants exhibit improved affinity for selective inhibitors of ATR.•Obtained crystal structures of the PI3Kα mutants in complex with ATR inhibitors•Insights into the key binding and structural features for the ATR inhibitors
RAS oncogenes have been implicated in >30% of human cancers, all representing high unmet medical need. The exquisite dependency on CRAF kinase in KRAS mutant tumors has been established in ...genetically engineered mouse models and human tumor cells. To date, many small molecule approaches are under investigation to target CRAF, yet kinase-selective and cellular potent inhibitors remain challenging to identify. Herein, we describe 14 (RAF709) Aversa , Biaryl amide compounds as kinase inhibitors and their preparation. WO 2014151616, 2014 , a selective B/C RAF inhibitor, which was developed through a hypothesis-driven approach focusing on drug-like properties. A key challenge encountered in the medicinal chemistry campaign was maintaining a balance between good solubility and potent cellular activity (suppression of pMEK and proliferation) in KRAS mutant tumor cell lines. We investigated the small molecule crystal structure of lead molecule 7 and hypothesized that disruption of the crystal packing would improve solubility, which led to a change from N-methylpyridone to a tetrahydropyranyl oxy-pyridine derivative. 14 proved to be soluble, kinase selective, and efficacious in a KRAS mutant xenograft model.
A HTS campaign identified compound 1, an excellent hit-like molecule to initiate medicinal chemistry efforts to optimize a dual ROCK1 and ROCK2 inhibitor. Substitution (2-Cl, 2-NH2, 2-F, 3-F) of the ...pyridine hinge binding motif or replacement with pyrimidine afforded compounds with a clean CYP inhibition profile. Cocrystal structures of an early lead compound were obtained in PKA, ROCK1, and ROCK2. This provided critical structural information for medicinal chemistry to drive compound design. The structural data indicated the preferred configuration at the central benzylic carbon would be (R), and application of this information to compound design resulted in compound 16. This compound was shown to be a potent and selective dual ROCK inhibitor in both enzyme and cell assays and efficacious in the retinal nerve fiber layer model after oral dosing. This tool compound has been made available through the AbbVie Compound Toolbox. Finally, the cocrystal structures also identified that aspartic acid residues 176 and 218 in ROCK2, which are glutamic acids in PKA, could be targeted as residues to drive both potency and kinome selectivity. Introduction of a piperidin-3-ylmethanamine group to the compound series resulted in compound 58, a potent and selective dual ROCK inhibitor with excellent predicted drug-like properties.
The discovery and development of new antibiotics capable of curing infections due to multidrug-resistant and pandrug-resistant Gram-negative bacteria are a major challenge with fundamental importance ...to our global healthcare system. Part of our broad program at Novartis to address this urgent, unmet need includes the search for new agents that inhibit novel bacterial targets. Here we report the discovery and hit-to-lead optimization of new inhibitors of phosphopantetheine adenylyltransferase (PPAT) from Gram-negative bacteria. Utilizing a fragment-based screening approach, we discovered a number of unique scaffolds capable of interacting with the pantetheine site of E. coli PPAT and inhibiting enzymatic activity, including triazolopyrimidinone 6. Structure-based optimization resulted in the identification of two lead compounds as selective, small molecule inhibitors of bacterial PPAT: triazolopyrimidinone 53 and azabenzimidazole 54 efficiently inhibited E. coli and P. aeruginosa PPAT and displayed modest cellular potency against the efflux-deficient E. coli ΔtolC mutant strain.
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