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The computational construction of small organic molecules (de novo design), directly in a protein binding site, is an effective means for generating novel ligands tailored to fit the pocket environment. In this work, we present two new methods, which aim to improve de novo design outcomes using (1) biasing algorithms to prioritize selection and/or acceptance of fragments and torsions during growth, and (2) parallel‐based clustering and pruning algorithms to remove duplicate molecules as candidate fragment are added. Large‐scale testing encompassing thousands of simulations were employed to interrogate the methods in terms of multiple metrics which include numbers of duplicate molecules generated, pairwise‐similarity, focused library reconstruction rates, fragment and torsion frequencies, fragment and torsion rank scores, interaction energy and drug‐likeness scores, and 3D pose comparisons. The biasing algorithms, particularly those that include fragment and torsion components simultaneously, led to molecules that more closely mimicked the distributions of fragments and torsions found in drug‐like libraries. The new parallel‐based clustering and pruning algorithms, compared with the existing serial approach, also led to larger ensembles comprised of topologically unique molecules with much greater efficiency by removing redundant growth paths. [ABSTRACT FROM AUTHOR]

As a complement to virtual screening, de novo design of small molecules is an alternative approach for identifying potential drug candidates. Here, we present a new 3D genetic algorithm to evolve molecules through breeding, mutation, fitness pressure, and selection. The method, termed DOCK_GA, builds upon and leverages powerful sampling, scoring, and searching routines previously implemented into DOCK6. Three primary experiments were used during development: Single‐molecule evolution evaluated three selection methods (elitism, tournament, and roulette), in four clinically relevant systems, in terms of mutation type and crossover success, chemical properties, ensemble diversity, and fitness convergence, among others. Large scale benchmarking assessed performance across 651 different protein‐ligand systems. Ensemble‐based evolution demonstrated using multiple inhibitors simultaneously to seed growth in a SARS‐CoV‐2 target. Key takeaways include: (1) The algorithm is robust as demonstrated by the successful evolution of molecules across a large diverse dataset. (2) Users have flexibility with regards to parent input, selection method, fitness function, and molecular descriptors. (3) The program is straightforward to run and only requires a single executable and input file at run‐time. (4) The elitism selection method yields more tightly clustered molecules in terms of 2D/3D similarity, with more favorable fitness, followed by tournament and roulette. [ABSTRACT FROM AUTHOR]

Background: Adams-Oliver syndrome (AOS) (#614,219) is a multiple malformation disorder characterized by the presence of aplasia cutis congenita (ACC) and transverse terminal limb defects (TTLD). Methods and results: We describe a confirmed case of AOS with a novel pathogenic variation in Dedicator Of Cytokinesis 6 (DOCK6) gene, with neurological abnormalities, characterized by the presence of a multiple malformation entity with extensive cardiological and neurological abnormalities. Conclusions: In AOS, genotype-phenotype correlations have been described. DOCK6 mutations appear to be related with congenital cardiac and central nervous system malformations associated with intellectual disability, as illustrated in the present case. [ABSTRACT FROM AUTHOR]

Glomalin related soil protein produced by mycorrhizal fungus such as Rhizophagus irregularis (GiHsp60) has been termed as a miracle protein for soil sustainability. In this study we propose an integrative in silico approach to explain the mode of interaction between GiHsp60 and the soil organic matter (SOM). In the first step of the study, the three-dimensional (3D) structure of GiHsp60 was constructed using the SWISS-MODEL server; while in the second step, the SOM model was optimized using the Gaussian program, followed by docking-molecular dynamics simulation studies to investigate the stability and interactions of GiHsp60_SOM complex, using Dock and Amber packages respectively. The quality of the modeled 3D structure of GiHsp60 was reasonably good based on reports generated by different validation servers. The docking results suggested that both Van der Waals (grid_vdw = −34.73 kcal mol−1) and electrostatic interactions (grid_es = −3.28 kcal mol−1) were responsible for the interaction between the protein and the ligand. Molecular dynamics simulation was used to compute the free energy of binding of GiHsp60_SOM complex under explicit conditions. The study further revealed that H-bonding, electrostatic, and Van der Waals forces, followed by hydrophilic and hydrophobic interactions were the forces responsible for the binding of GiHsp60 with SOM. The present investigation is perhaps a benchmark study, which explains the interaction between GiHsp60 and SOM at the molecular level using computational approach. Results from this study can enable agriculture molecular biologists in their efforts to explore GiHsp60 as a potential soil conditioner, which in turn will lead ways to enhance inputs for sustainable agricultural systems and boost agricultural productivity. [ABSTRACT FROM AUTHOR]

Adams-Oliver syndrome (AOS) is characterized by a combination of congenital scalp defects (aplasia cutis congenita) and terminal transverse limb malformations of variable severity. When neurological findings are present, patients are reported as AOS variants. We describe a child with compound heterozygosity of the DOCK6 gene, aplasia cutis, terminal transverse limb defects, cardiovascular impairment, intellectual disability, and brain malformations with intracranial calcifications. He suffers from a severe refractory epileptic encephalopathy characterized by polymorphic seizures with prolonged periods of electroencephalogram (EEG), continuous epileptiform activity related to clinical inactivity, and closure of eyes with an "ON-OFF" behavior. [ABSTRACT FROM AUTHOR]

The Adams-Oliver syndrome (AOS) is defined as aplasia cutis congenita (ACC) with transverse terminal limb defects (TTLD). Frequencies of associated anomalies are not well characterized. Six causative genes have been identified: ARHGAP31, DOCK6, EOGT, RBPJ, NOTCH1, and DLL4. We review 385 previously described individuals (139 non-familial and 246 familial probands and family members) and add clinical data on 13 previously unreported individuals with AOS. In addition to ACC and TTLD, the most commonly associated anomalies included a wide variety of central nervous system (CNS) anomalies and congenital heart defects each seen in 23%. CNS anomalies included structural anomalies, microcephaly, vascular defects, and vascular sequelae. CNS migration defects were common. Cutis marmorata telangiectasia congenita (CMTC) was found in 19% of the study population and other vascular anomalies were seen in 14%. Hemorrhage was listed as the cause of death for five of 25 deaths reported. A relatively large number of non-familial probands were reported to have hepatoportal sclerosis with portal hypertension and esophageal varices. Non-familial probands were more likely to have additional anomalies than were familial probands. The data reported herein provide a basis for refining the diagnostic features of AOS and suggest management recommendations for probands newly diagnosed with AOS. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT Adams-Oliver syndrome (AOS) is characterized by the association of aplasia cutis congenita with terminal transverse limb defects, often accompanied by additional cardiovascular or neurological features. Both autosomal-dominant and autosomal-recessive disease transmission have been observed, with recent gene discoveries indicating extensive genetic heterogeneity. Mutations of the DOCK6 gene were first described in autosomal-recessive cases of AOS and only five DOCK6-related families have been reported to date. Recently, a second type of autosomal-recessive AOS has been attributed to EOGT mutations in three consanguineous families. Here, we describe the identification of 13 DOCK6 mutations, the majority of which are novel, across 10 unrelated individuals from a large cohort comprising 47 sporadic cases and 31 AOS pedigrees suggestive of autosomal-recessive inheritance. DOCK6 mutations were strongly associated with structural brain abnormalities, ocular anomalies, and intellectual disability, thus suggesting that DOCK6-linked disease represents a variant of AOS with a particularly poor prognosis. [ABSTRACT FROM AUTHOR]

Adams-Oliver syndrome (AOS) is a rare malformation syndrome characterized by the presence of two anomalies: aplasia cutis congenita of the scalp and transverse terminal limb defects. Many affected individuals also have additional malformations, including a variety of intracranial anomalies such as periventricular calcification in keeping with cerebrovascular microbleeds, impaired neuronal migration, epilepsy, and microcephaly. Cardiac malformations can be present, as can vascular dysfunction in the forms of cutis marmorata telangiectasia congenita, pulmonary vein stenoses, and abnormal hepatic microvasculature. Elucidated genetic causes include four genes in different pathways, leading to a model of AOS as a multi-pathway disorder. We identified an infant with mild aplasia cutis congenita and terminal transverse limb defects, developmental delay and a severe, diffuse angiopathy with incomplete microvascularization. Whole-genome sequencing documented two rare truncating variants in DOCK6, a gene associated with a type of autosomal recessive AOS that recurrently features periventricular calcification and impaired neurodevelopment. We highlight an unexpectedly high frequency of likely deleterious mutations in this gene in the general population, relative to the rarity of the disease, and discuss possible explanations for this discrepancy. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Molecular modelling studies were performed on some previously reported novel quinoxaline-2-carboxamide 1,4-di-N-oxide derivatives (series 1-9). Using the LigandScout program, a pharmacophore model was developed to further optimize the antimycobacterial activity of this series of compounds. Using the Dock6 program, docking studies were performed in order to investigate the mode of binding of these compounds. The molecular modeling study allowed us to confirm the preferential binding mode of these quinoxaline- 2-carboxamide 1,4-di-N-oxide derivatives inside the active site. The obtained binding mode was as same as that of the novobiocin X-ray structure. [ABSTRACT FROM AUTHOR]

In our effort for synthesis of selective COX2 inhibitors, certain new 2,4-thiazolidinedione derivatives were synthesized. It necessitates preparation of potassium salt of 2,4-thiazolidinedione 2, which condensed with intermediate 4a. The resulting 3-[2-(4-methylphenyl)-2-oxo-1-phenylethyl]-2,4-thiazolidinedione 8 was condensed with appropriate aldehyde to afford compounds 10a, 10i-l, 10o and 10p. Compounds (9a-l, 10a-n, 10p, 11 and 12) were obtained through the preparation of 5-arylmethylidene-2,4-thiazolidinediones 6a-p and reaction of its potassium salt 7a-p with compounds 4a, 4b, and 5. Some compounds displayed significant analgesic activity as compared to reference standards. The anti-inflammatory activity of the synthesized compounds revealed that intermediate 8 and compounds 9c, 10c and 10d showed good results. Compound 10c produced no significant mucosal injury. HipHop methodology of Catalyst program was used to build up hypothetical model of selective COX2 inhibitors followed by fitting the synthesized compounds to this model. Compounds 10c and 10d were suspected to be promising selective COX2 inhibitors. Also, compounds (6c, 8, 9a,c,d,k, 10a,c,d,k, 11 and 12) were docked into COX1 and COX2 X-ray structures, using DOCK6 program. Docking results suggested that several of these derivatives are active COX inhibitors with a significant preference for COX2. [ABSTRACT FROM AUTHOR]

Probing protein surfaces to accurately predict the binding site and conformation of a small molecule is a challenge currently addressed through mainly two different approaches: blind docking and cavity detection-guided docking. Although cavity detection-guided blind docking has yielded high success rates, it is less practical when a large number of molecules must be screened against many detected binding sites. On the other hand, blind docking allows for simultaneous search of the whole protein surface, which however entails the loss of accuracy and speed. To bridge this gap, in this study, we developed and tested BLinDPyPr, an automated pipeline which uses FTMap and DOCK6 to perform a hybrid blind docking strategy. Through our algorithm, FTMap docked probe clusters are converted into DOCK6 spheres for determining binding regions. Because these spheres are solely derived from FTMap probes, their locations are contained in and specific to multiple potential binding pockets, which become the regions that are simultaneously probed and chosen by the search algorithm based on the properties of each candidate ligand. This method yields pose prediction results (45.2–54.3% success rates) comparable to those of site-specific docking with the classic DOCK6 workflow (49.7–54.3%) and is half as time-consuming as the conventional blind docking method with DOCK6. [ABSTRACT FROM AUTHOR]