The novel heterozygous Thr377Arg MYOC mutation causes severe Juvenile Open Angle Glaucoma in a large Pakistani family

Glaucoma is one of the major causes of blindness worldwide with characteristic optic disc changes and elevated intraocular pressure. It is subcategorized into Primary Open Angle Glaucoma (POAG) and Juvenile Open Angle Glaucoma (JOAG) depending upon age of the disease onset. Myocilin (MYOC) is the frequently mutated gene in familial cases of glaucoma. MYOC mutations show variable phenotype and penetrance. This study was aimed to identify disease causing mutation in 8 affected of a consanguineous family diagnosed with severe form of Juvenile Open Angle Glaucoma. Homozygosity mapping with four microsatellite markers and subsequent direct sequencing of MYOC revealed a novel heterozygous transition c.1130 C>G, substituting Threonine in to Arginine at codon 377 (p.Thr377Arg) of MYOC. This mutation was segregating with phenotype in all affected and was not found in control subjects. Ophthalmological findings revealed JOAG with severe and rapidly progressive phenotype. The age of onset was in the first decade of life and maximum Intra Ocular Pressure (IOP) recorded was 25 mm Hg. Bioinformatic tools predicted C to G transition at c.1130 as pathogenic and no structural changes were predicted in protein. This is the first report of novel MYOC mutation from Pakistan; segregating as autosomal dominant trait in large family diagnosed with JOAG. Identification of novel disease causing allele in MYOC indicates genetic heterogeneity of the population. This finding will help to provide genetic counseling to the affected family and carriers of this mutation may be advised for early therapeutic intervention to avoid irreversible visual loss.     

Dynamic and Structural Changes in the Minimally Restructuring EcoRI Bound to a Minimally Mutated DNA Chain

Abstract

The dynamics of a protein plays an important role in protein functionality. Here, we examine the differences in the dynamics of a minimally restructuring protein, EcoRI, when it is bound to its cognate DNA and to a noncognate sequence which differs by just a single basepair. Molecular dynamics simulations of the complexes and essential dynamics analyses reveal that the overall dynamics of the protein subunits change from a coordinated motion in the cognate complex to a scrambled motion in the noncognate complex. This dynamical difference extends to the protein-DNA interface where EcoRI tries to constrict the DNA in the cognate complex. In the noncognate complex, absence of the constricting motion of interfacial residues, overall change in backbone dynamics and structural relaxation of the arms enfolding the DNA leave the DNA less-kinked relative to the situation in the cognate complex, thus indicating that the protein is poised for linear diffusion along the DNA rather than for catalytic action. In a larger context, the results imply that the DNA sequences dictate protein dynamics and that when a protein chances upon the recognition sequence some of the key domains of the protein undergo dynamical changes that prepare the protein for eventual catalytic action.     

Purification and characterization of alkaline soda-bleach stable protease from Bacillus sp. APP-07 isolated from Laundromat soil

The detergent-compatible alkaline protease was produced from the bacterial strain Bacillus sp. APP-07 isolated from Laundromat soil of Solapur, Maharashtra, India. The culture was grown in 1000?ml capacity baffled flask with a working volume of 100?ml and incubated at 55?°C for 33?h on a rotary shaker. After incubation, alkaline protease was partially purified by the sequential method of acetone precipitation followed by nominal molecular weight limit (NMWL) cut-off ultrafiltration using 50?K and 10?K filters. Finally, Sephadex G-100 gel filtration chromatographic purification was performed to obtain 3.12 fold purified alkaline protease enzyme with a 66.67% final yield. The purified enzyme showed 31907.269 units (U) of enzyme activity containing 8741.718?U/mg of specific enzyme activity. The molecular weight of the enzyme was confirmed about 33.0?kDa (kDa) by the SDS-PAGE analysis. The purified enzyme was stable at higher pH and temperature range, with an optimum pH 10.5 and temperature 55?°C. The enzyme showed excellent stability and compatibility in various detergents, surfactants, bleach, and oxidizing agents. The enzyme activity enhanced in the presence of Ca²⁺, Cu²⁺, and surfactants, whereas; the phenylmethylsulphonyl fluoride (PMSF) and Diisopropyl fluorophosphate (DFP) completely inhibit the enzymatic activity, which pointed out that the enzyme affiliated to serine-centered metalloproteases family.In conclusion, the remarkable tolerance and stability of the enzyme explored the promising candidature for the several potential applications in the laundry detergents. The sustainability of the enzyme might serve several possible applications in the laundry detergents, leather industries, and other harsh industrial processes.     

Abnormal Fixational Eye Movements in Amblyopia

Purpose

Fixational saccades shift the foveal image to counteract visual fading related to neural adaptation. Drifts are slow eye movements between two adjacent fixational saccades. We quantified fixational saccades and asked whether their changes could be attributed to pathologic drifts seen in amblyopia, one of the most common causes of blindness in childhood.

Methods

Thirty-six pediatric subjects with varying severity of amblyopia and eleven healthy age-matched controls held their gaze on a visual target. Eye movements were measured with high-resolution video-oculography during fellow eye-viewing and amblyopic eye-viewing conditions. Fixational saccades and drifts were analyzed in the amblyopic and fellow eye and compared with controls.

Results

We found an increase in the amplitude with decreased frequency of fixational saccades in children with amblyopia. These alterations in fixational eye movements correlated with the severity of their amblyopia. There was also an increase in eye position variance during drifts in amblyopes. There was no correlation between the eye position variance or the eye velocity during ocular drifts and the amplitude of subsequent fixational saccade. Our findings suggest that abnormalities in fixational saccades in amblyopia are independent of the ocular drift.

Discussion

This investigation of amblyopia in pediatric age group quantitatively characterizes the fixation instability. Impaired properties of fixational saccades could be the consequence of abnormal processing and reorganization of the visual system in amblyopia. Paucity in the visual feedback during amblyopic eye-viewing condition can attribute to the increased eye position variance and drift velocity.     

Risk factors for acquisition of extended spectrum beta lactamase producing Escherichia coli and Klebsiella pneumoniae in North-Indian hospitals

Multidrug resistance and production of extended spectrum β-lactamases (ESBLs) by enteric gram negative rods in hospitals and community continue to be a matter of scientific concern. This retrospective study was executed to assess the prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae at two North Indian hospitals and to determine the risk factors associated with the acquisition of these organisms. A total of 346 bacterial isolates were obtained. Of these, 48.27% (n = 167) were confirmed to be ESBL producers while 51.73% (n = 179) were non ESBL-producers. Among the ESBL producers, 55.69% (n = 93) were E. coli and 44.31% (n = 74) were K. pneumoniae. ESBL producing isolates showed co-resistance to multitude of antibiotics tested. Length of hospital stay (>3 days) and previous exposure to antibiotics were found as significant risk factors (p = 0.01 and 0.02) associated with the acquisition of ESBL-producing E. coli and K. pneumoniae isolates. Imipenem and meropenem can be suggested as drugs of choice in our study.     

Discovery and pharmacological evaluation of indole derivatives as potent and selective RORγt inverse agonist for multiple autoimmune conditions

Targeting nuclear receptor RORγ is recognized to be beneficial in multiple autoimmune disorders. We disclosed new indole analogues as potent RORγ inverse agonists. RO-2 as one of the potent and orally bioavailable compounds was evaluated in various models of autoimmune disorder. It showed potent suppression of downstream markers of RORγt activity in murine and human primary cells, ex vivo PD assay and in multiple animal models of autoimmune diseases. The results indicate the potential of these indole analogues as orally bioavailable small molecule inverse agonists of RORγt, efficacious in various Th17 driven models of autoimmune disorders.     

Druggability Simulations and X-Ray Crystallography Reveal a Ligand-Binding Site in the GluA3 AMPA Receptor N-Terminal Domain

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