We present the results for CAPRI Round 30, the first joint CASP-CAPRI experiment, which brought together experts from the protein structure prediction and protein-protein docking communities. The Round comprised 25 targets from amongst those submitted for the CASP11 prediction experiment of 2014. The targets included mostly homodimers, a few homotetramers, and two heterodimers, and comprised protein chains that could readily be modeled using templates from the Protein Data Bank. On average 24 CAPRI groups and 7 CASP groups submitted docking predictions for each target, and 12 CAPRI groups per target participated in the CAPRI scoring experiment. In total more than 9500 models were assessed against the 3D structures of the corresponding target complexes. Results show that the prediction of homodimer assemblies by homology modeling techniques and docking calculations is quite successful for targets featuring large enough subunit interfaces to represent stable associations. Targets with ambiguous or inaccurate oligomeric state assignments, often featuring crystal contact-sized interfaces, represented a confounding factor. For those, a much poorer prediction performance was achieved, while nonetheless often providing helpful clues on the correct oligomeric state of the protein. The prediction performance was very poor for genuine tetrameric targets, where the inaccuracy of the homology-built subunit models and the smaller pair-wise interfaces severely limited the ability to derive the correct assembly mode. Our analysis also shows that docking procedures tend to perform better than standard homology modeling techniques and that highly accurate models of the protein components are not always required to identify their association modes with acceptable accuracy.
This study demonstrates that the chromosome of the hyperthermophilic archaeon Thermococcus kodakarensis is organized into a heterogeneous structure created with histone and a novel protein TK0471/TrmBL2. TK0471/TrmBL2 plays dual roles as a chromosomal protein and as a global transcriptional repressor, and it is conserved in some archaeal and bacterial species.
Protein transport systems are fundamentally important for maintaining mitochondrial function. Nevertheless, mitochondrial protein translocases such as the kinetoplastid ATOM complex have recently been shown to vary in eukaryotic lineages. Various evolutionary hypotheses have been formulated to explain this diversity. To resolve any contradiction, estimating the primitive state and clarifying changes from that state are necessary. Here, we present more likely primitive models of mitochondrial translocases, specifically the translocase of the outer membrane (TOM) and translocase of the inner membrane (TIM) complexes, using scrutinized phylogenetic profiles. We then analyzed the translocases’ evolution in eukaryotic lineages. Based on those results, we propose a novel evolutionary scenario for diversification of the mitochondrial transport system. Our results indicate that presequence transport machinery was mostly established in the last eukaryotic common ancestor, and that primitive translocases already had a pathway for transporting presequence-containing proteins. Moreover, secondary changes including convergent and migrational gains of a presequence receptor in TOM and TIM complexes, respectively, likely resulted from constrained evolution. The nature of a targeting signal can constrain alteration to the protein transport complex.
A series of tetrahydronaphthyridine derivatives as novel RORγt inverse agonists were designed and synthesized. We reduced the lipophilicity of tetrahydroisoquinoline compound 1 by replacement of the trimethylsilyl group and SBDD-guided scaffold exchange, which successfully afforded compound 7 with a lower log D value and tolerable in vitro activity. Consideration of LLE values in the subsequent optimization of the carboxylate tether led to the discovery of [ cis-3-({(5 R)-5-[(7-fluoro-1,1-dimethyl-2,3-dihydro-1 H-inden-5-yl)carbamoyl]-2-methoxy-7,8-dihydro-1,6-naphthyridin-6(5 H)-yl}carbonyl)cyclobutyl]acetic acid, TAK-828F (10), which showed potent RORγt inverse agonistic activity, excellent selectivity against other ROR isoforms and nuclear receptors, and a good pharmacokinetic profile. In animal studies, oral administration of compound 10 exhibited robust and dose-dependent inhibition of IL-17A cytokine expression in a mouse IL23-induced gene expression assay. Furthermore, development of clinical symptoms in a mouse experimental autoimmune encephalomyelitis model was significantly reduced. Compound 10 was selected as a clinical compound for the treatment of Th17-driven autoimmune diseases.
Multi-enzymatic syntheses of L-[P-"%]tryptophan and 5hydroxy-L-[P-llCItryptophan from racemic [3-"C]alanine are reported. "C-Labelled alanine was prepared by an alkylation of a glycine derivative, N-and subsequent hydrolysis. The enzymatic syntheses were carried out in a one-pot reaction using Damino acid oxidase/catalase, glutamic-pyruvic transaminase, and tryptophanase. The total synthesis time was 50 t o 55 min, including h.p.1.c. purification, counted from the start of [llC]methyl iodide synthesis. The yields were ca. 25%, decay corrected, of purified sterilized enantiomerically pure L-[P-"Cltryptophan and 5hydroxy-L-[P-"Cltryptophan with radiochemical purities of > 98%. The
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