42 research outputs found
Identification of 3-chymotrypsin like protease (3CLPro) inhibitors as potential anti-SARS-CoV-2 agents.
Emerging outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is a major threat to public health. The morbidity is increasing due to lack of SARS-CoV-2 specific drugs. Herein, we have identified potential drugs that target the 3-chymotrypsin like protease (3CLpro), the main protease that is pivotal for the replication of SARS-CoV-2. Computational molecular modeling was used to screen 3987 FDA approved drugs, and 47 drugs were selected to study their inhibitory effects on SARS-CoV-2 specific 3CLpro enzyme in vitro. Our results indicate that boceprevir, ombitasvir, paritaprevir, tipranavir, ivermectin, and micafungin exhibited inhibitory effect towards 3CLpro enzymatic activity. The 100âns molecular dynamics simulation studies showed that ivermectin may require homodimeric form of 3CLpro enzyme for its inhibitory activity. In summary, these molecules could be useful to develop highly specific therapeutically viable drugs to inhibit the SARS-CoV-2 replication either alone or in combination with drugs specific for other SARS-CoV-2 viral targets
Indigo Formation and Rapid NADPH Consumption Provide Robust Prediction of Raspberry Ketone Synthesis by Engineered Cytochrome P450 BM3
Natural raspberry ketone has a high value in the flavor, fragrance and pharmaceutical industries. Its extraction is costly, justifying the search for biosynthetic routes. We hypothesized that cytochrome P450 BM3 (P450 BM3) could be engineered to catalyze the hydroxylation of 4âphenylâ2âbutanone, a naturally sourceable precursor, to raspberry ketone. The synthesis of indigo by variants of P450 BM3 has previously served as a predictor of promiscuous oxidation reactions. To this end, we screened 53 activeâsite variants of P450 BM3 using orthogonal highâthroughput workflows to identify the most streamlined route to all indigoâforming variants. Among the three known and 13 new indigoâforming variants, eight hydroxylated 4âphenylâ2âbutanone to raspberry ketone. Previously unreported variant A82Q displayed the highest initial rates and coupling efficiencies in synthesis of indigo and of raspberry ketone. It produced the highest total concentration of raspberry ketone despite producing less total indigo than previously reported variants. Its productivity, although modest, clearly demonstrates the potential for development of a biocatalytic route to raspberry ketone. In addition to validating indigo as a robust predictor of this promiscuous activity, we demonstrate that monitoring rapid NADPH consumption serves as an alternative predictor of a promiscuous reactivity in P450 BM3
The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima.
Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific life history.This work was supported by the following grants: NHGRIU54HG003273 to R.A.G; EU Marie Curie ITN #215781 âEvonetâ to M.A.; a Wellcome Trust Value in People (VIP) award to C.B. and Wellcome Trust graduate studentship WT089615MA to J.E.G; Marine
rhythms of Lifeâ of the University of Vienna, an FWF (http://www.fwf.ac.at/) START award (#AY0041321) and HFSP (http://www.hfsp.org/) research grant (#RGY0082/2010) to KT-ÂâR; MFPL Vienna International PostDoctoral Program for Molecular Life Sciences (funded by Austrian Ministry of Science and Research and City of Vienna, Cultural Department -ÂâScience and Research to T.K; Direct Grant (4053034) of the Chinese University of Hong Kong to J.H.L.H.; NHGRI HG004164 to G.M.; Danish Research Agency (FNU), Carlsberg Foundation, and Lundbeck Foundation to C.J.P.G.; U.S. National Institutes of Health R01AI55624 to J.H.W.; Royal Society University Research fellowship to F.M.J.; P.D.E. was supported by the BBSRC via the Babraham Institute;This is the final version of the article. It first appeared from PLOS via http://dx.doi.org/10.1371/journal.pbio.100200
In situ guided tissue regeneration in musculoskeletal diseases and aging: Implementing pathology into tailored tissue engineering strategies
In situ guided tissue regeneration, also addressed as in situ tissue engineering or endogenous regeneration, has a great potential for population-wide âminimal invasiveâ applications. During the last two decades, tissue engineering has been developed with remarkable in vitro and preclinical success but still the number of applications in clinical routine is extremely small. Moreover, the vision of population-wide applications of ex vivo tissue engineered constructs based on cells, growth and differentiation factors and scaffolds, must probably be deemed unrealistic for economic and regulation-related issues. Hence, the progress made in this respect will be mostly applicable to a fraction of post-traumatic or post-surgery situations such as big tissue defects due to tumor manifestation. Minimally invasive procedures would probably qualify for a broader application and ideally would only require off the shelf standardized products without cells. Such products should mimic the microenvironment of regenerating tissues and make use of the endogenous tissue regeneration capacities. Functionally, the chemotaxis of regenerative cells, their amplification as a transient amplifying pool and their concerted differentiation and remodeling should be addressed. This is especially important because the main target populations for such applications are the elderly and diseased. The quality of regenerative cells is impaired in such organisms and high levels of inhibitors also interfere with regeneration and healing. In metabolic bone diseases like osteoporosis, it is already known that antagonists for inhibitors such as activin and sclerostin enhance bone formation. Implementing such strategies into applications for in situ guided tissue regeneration should greatly enhance the efficacy of tailored procedures in the future
A many-analysts approach to the relation between religiosity and well-being
The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported ÎČ=0.120). For the second research question, this was the case for 65% of the teams (median reported ÎČ=0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates
A Many-analysts Approach to the Relation Between Religiosity and Well-being
The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N = 10, 535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported ÎČ = 0.120). For the second research question, this was the case for 65% of the teams (median reported ÎČ = 0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates
Enzyme engineering: A synthetic biology approach for more effective library generation and automated high-throughput screening.
The Golden Gate strategy entails the use of type IIS restriction enzymes, which cut outside of their recognition sequence. It enables unrestricted design of unique DNA fragments that can be readily and seamlessly recombined. Successfully employed in other synthetic biology applications, we demonstrate its advantageous use to engineer a biocatalyst. Hot-spots for mutations were individuated in three distinct regions of Candida antarctica lipase A (Cal-A), the biocatalyst chosen as a target to demonstrate the versatility of this recombination method. The three corresponding gene segments were subjected to the most appropriate method of mutagenesis (targeted or random). Their straightforward reassembly allowed combining products of different mutagenesis methods in a single round for rapid production of a series of diverse libraries, thus facilitating directed evolution. Screening to improve discrimination of short-chain versus long-chain fatty acid substrates was aided by development of a general, automated method for visual discrimination of the hydrolysis of varied substrates by whole cells
Substrate-Specific Screening for Mutational Hotspots Using Biased Molecular Dynamics Simulations
Prediction of substrate-specific
mutational hotspots for enzyme
engineering is a complex and computationally intensive task. This
becomes particularly challenging when the available crystal structures
have no ligand, bind a distant homologue of the desired substrate,
or hold the ligand in a nonproductive conformation. To address that
shortcoming, we present a combined molecular dynamics simulation and
molecular docking protocol to predict the conformation of catalytically
relevant enzymeâligand complexes even in the absence of a ligand-bound
structure. We applied the adaptive biasing force method to predict
the ligand-specific path of diffusion of a fatty acid substrate from
the bulk media into the active site of cytochrome P450 CYP102A1 (BM3).
Starting with a ligand-free crystal structure, we successfully identified
all residues known to be involved in palmitic acid binding to BM3.
The binding trajectory also revealed a yet unknown binding residue,
Q73, which we confirmed experimentally. Building the free-energy landscape
illustrates that, similar to human cytochrome P450s, binding is multistep
and does not follow simple MichaelisâMenten kinetics. We confirmed
the robustness of the method using a structurally distinct substrate,
the small aromatic indole. We then applied the predicted BM3:palmitate
complex to molecular docking of a library of 29 palmitate analogues.
This produced catalytically relevant binding poses for the entire
library, while docking directly into ligand-free and ligand-bound
crystal structures gave poor results. This fast and simple computational
method is broadly applicable for predicting binding hotspots in a
substrate-specific manner and has the potential to drastically reduce
the experimental screening effort to tailor an enzyme to substrates
of interest
Substrate-Specific Screening for Mutational Hotspots Using Biased Molecular Dynamics Simulations
Prediction of substrate-specific
mutational hotspots for enzyme
engineering is a complex and computationally intensive task. This
becomes particularly challenging when the available crystal structures
have no ligand, bind a distant homologue of the desired substrate,
or hold the ligand in a nonproductive conformation. To address that
shortcoming, we present a combined molecular dynamics simulation and
molecular docking protocol to predict the conformation of catalytically
relevant enzymeâligand complexes even in the absence of a ligand-bound
structure. We applied the adaptive biasing force method to predict
the ligand-specific path of diffusion of a fatty acid substrate from
the bulk media into the active site of cytochrome P450 CYP102A1 (BM3).
Starting with a ligand-free crystal structure, we successfully identified
all residues known to be involved in palmitic acid binding to BM3.
The binding trajectory also revealed a yet unknown binding residue,
Q73, which we confirmed experimentally. Building the free-energy landscape
illustrates that, similar to human cytochrome P450s, binding is multistep
and does not follow simple MichaelisâMenten kinetics. We confirmed
the robustness of the method using a structurally distinct substrate,
the small aromatic indole. We then applied the predicted BM3:palmitate
complex to molecular docking of a library of 29 palmitate analogues.
This produced catalytically relevant binding poses for the entire
library, while docking directly into ligand-free and ligand-bound
crystal structures gave poor results. This fast and simple computational
method is broadly applicable for predicting binding hotspots in a
substrate-specific manner and has the potential to drastically reduce
the experimental screening effort to tailor an enzyme to substrates
of interest
Summary of sequencing results defining the quality of the random library (library 10, Table 1).
<p>Summary of sequencing results defining the quality of the random library (library 10, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0171741#pone.0171741.t001" target="_blank">Table 1</a>).</p