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Background Antimicrobial resistance in Neisseria gonorrhoeae (NG), the causative organism of gonorrhea, has posed a serious threat worldwide. Gonorrhea is a sexually transmitted disease with a high morbidity burden and is an important cause of pelvic inflammatory disease. The failure of recommended dual therapy with ceftriaxone and azithromycin has compromised the general and reproductive health of infected individuals. Thereby, Neisseria gonorrhoeae was recently classified as a ‘Priority 2’ microorganism by the World Health Organization. Consequently, persistent attempts are under way to discover novel drug targets as well as new drugs to fight against Neisseria. In this direction, considerable number of phytochemicals have been reconnoitred for their remedial intercession via targeting bacterial proteins. Methods MurI gene is specific to the bacterial kingdom, it can be exploited as a potential drug target for the treatment of bacterial diseases. Accordingly, diverse families of phytochemicals were screened in silico for their binding affinity with NG-MurI protein. Esculetin, one of the shortlisted compounds, was evaluated for its functional, structural and anti-bacterial activity. MurI was cloned, expressed and purified to homogeneity and used for testing the effect of esculetin on its racemase activity under invitro conditions. We further evaluated the effect of esculetin on sensitive and drug resistant strains of NG. Results We screened various classes of natural compounds and found esculetin, a coumarin derivative as a potent compound to target its effect on the growth of Neisseria gonorrhoeae.Treatment with esculetin resulted in growth inhibition, cell wall damage and altered permeability as revealed by fluorescence and electron microscopy. Furthermore, esculetin inhibited racemization activity of recombinant, purified MurI protein of NG, an important enzyme required for peptidoglycan biosynthesis. Conclusions Our results suggest that esculetin could be further explored as a lead compound for developing new drug molecules against multidrug resistant strains.

Context: Suicide is a disease and a global public health problem. Suicidology has come to become a topic of study for intervention and research. The serotonin (5-hydroxytryptamine [5HT]) system has remained a prime area of investigation. The neurons and platelets display structural and functional similarities. Ninety-nine percent of 5HT is contained in platelets, which shares similar 5HT uptake and release mechanisms with 5HT neurons. Aims: This study aims to study human self-destructive behavior (HSDB). Objectives: Exploring the biological (serotonin levels in platelets) and psychological aspects (impulsivity) of attempted suicide or HSDB. Settings and Design: Thirty-one patients, above the age of 18 years, with a recent history of HSDB, were studied and given an International Classification of Diseases-10 diagnosis, after a detailed interview. Subjects and Methods: For the platelet 5HT estimation, blood samples were collected, and enzyme immunometric assay carried out. Detailed assessment of the impulsivity was done by the 25-item structured diagnostic interview for borderlines by Zanarini et al. Statistical Analysis Used: We obtained both categorical and continuous data. Chi-square test, Fisher's test, Student's t-test, and Pearson's product moment correlation were used. Results: Female subjects outnumbered males by 2:1. Major depression, adjustment disorder, personality disorder were predominant diagnoses. The mean platelet serotonin concentration for males = 57.3 ng/ml, that of females = 56.05 ng/ml (P > 0.05). Platelet 5HT levels were found to be negatively correlated with impulsivity scores (P < 0.05). Conclusions: Platelet serotonin levels in our study sample were quite low when compared with those reported in published literature. Low serotonin levels were inversely related to impulsivity, but only in males.

Background N. gonorrhoeae, a major causative agent of STI, has acquired resistance to most of the commonly used drugs. Hence there is an urgent need to look for novel drug targets and new drugs to combat this disease. Although a large number of prokaryotic genomes have been sequenced, only a small percentage is completely annotated. Structure-function annotation of hypothetical proteins (HPs) can be exploited to identify novel drug targets. Methods Various web tools were used under stringent condition to predict the function of different HPs and to identify novel drug targets based on their cellular localization, domains, motifs and by using STRING (http://string-db.org/) to identify their potential interactions with other proteins. To predict drug targets, essential genes were identified using DEG database and BLASTed against proteome of Homo sapiens to exclude homologous proteins. Results Using bioinformatics tools, 206 HPs were analyzed for their subcellular localization. 140 HPs were predicted as cytoplasmic proteins and 10 as extracellular, Nine proteins in the outer membrane, seven as inner membrane whereas three in the periplasmic area. Using available tools, function to 32 HPs was assigned with high confidence; 11 proteins showed signal peptide whereas 21 proteins showed transmembrane helices. We predicted 19 proteins as putative enzymes crucial for the survival of Neisseria. These 19HPs were sub-classified as DNA modification system (5), transferases (3), hydrolase (3), FAD/NAD binding enzymes (5) and others (3). Other 12 HPs were characterized as transporter proteins including autotransporter (8), TonB dependent receptor (2), members of TAT pathway (1) and branched chain amino acid transporter (1). Two transporter proteins were predicted as adhesins and further classified as drug targets whereas five were predicted as vaccine candidates. We also predict five cytoplasmic and 4HPs localized in outer membrane as potential drug targets. Conclusion These results are expected to be helpful in the development of improved therapeutics. Disclosure No significant relationships.

Background Neisseria gonorrhoeae, a causative agent of gonorrhea, has developed resistance to most of the drugs and hence aptly declared as ‘Superbug’. Glutamate racemase (MurI) considered as an important drug target. Therefore, identification of novel drugs for the treatment of gonorrhea is urgently required. Methods The amino acid sequence of MurI of Neisseria gonorrhoeae (YP_208550) was retrieved from NCBI. Based on query coverage, e-score and percentage similarity, 3OUT (glutamate racemase from Francisella tularensis) was selected as template after PDB BLAST, homology model was generated by Modeller programme of Discovery Studio 4.0.Best model was selected based on DOPE score and PDF energy score and further verified by Verify-3D protocol and Ramachandran Plot. Receptor binding site was identified after superimposition of template structure and modelled structure and the co-crystalized ligand of the template was docked into the modeled MurI structure. Based on docking score, best pose was selected and receptor-ligand pharmacophore model was generated. Results The best homology model generated was selected based on the verify score of 107.93 from Verify 3D program of Discovery Studio 4.0. Validation of the selected model by Ramachandran plot showed214 residues (91.8%) fall in most favored region. RMSD of 0.2475 A0was generated by superimposition of query and template structures. Quality factorof 84% for the protein models was obtained using ERRAT.Six pharmacophores were generated using best docking pose between D-glutamate and MurI. These were subjected to virtual screening with DrugBank database.586 hits so obtained were filtered by fit value of 3.51which resulted in268 hits.These 268 hits were further subjected to Lipinski and veber filter followed by ADMET, gave 73 hits. These were subjected to energy minimization and docking to obtain the best hits. Conclusion The study identifies potential compounds that interact with active site of MurI protein, opening new avenues for the treatment option against multidrug resistant strains. Disclosure No significant relationships.

Background Neisseria gonorrhoeae (NG) is a sexually transmitted pathogen infecting both men and women. In spite of a number of antibiotics, gonorrhea (also known as “The Clap”), remains a frequently reported STI and is an important cause of pelvic inflammatory disease and infertility. Due to resistance to most of the currently used drugs, NG has been named as ‘Superbug’ posing a serious threat to gonorrhoea treatment worldwide. Therefore, there is an urgent need to find novel drug targets and to develop new antibacterial agents. Methods Using system biology to identify potential drug targets and the known inhibitors/drugs against homologous proteins, we identified a novel drug target, namely glutamate racemase (GR). This enzyme is involved in the early phase of peptidoglycan biosynthesis in both gram positive and gram negative bacteria. As protein-ligand interactions play a key role in structure-based drug design, we screened natural compounds for binding to NG-GR by carrying out docking studies, shortlisted the best docked compounds and evaluated them for their functional, structural and antibacterial activity. Results The computational analysis showed that the coumarin derivative-esculetin exhibited best binding affinity among all the tested compounds. Characterization of the biophysical properties of purified recombinant GR using circular dichroism, in the absence and presence of esculetin, indicated a change in protein conformation in the presence of esculetin. This change is the protein structure was associated with a concomitant inhibition of racemization activity of recombinant GR. Esculetin also inhibited the growth of the bacteria in culture both in time and concentration dependent manner. Conclusion In conclusion, these observations could provide impetus for further research in this direction. Better understanding of antibacterial mechanisms of esculetin will help in establishing lead molecules for the treatment of gonococcal infections. Disclosure No significant relationships.

Tuberculosis (TB) is caused by Mycobacterium tuberculosis (MTB), a highly infectious disease accounting for nearly 1.5 million deaths every year and has been a major global concern. Moreover, resistance to anti-TB drugs is an arduous obstacle to effective prevention, TB care and management. Therefore, incessant attempts are being made to identify novel drug targets and newer anti-tubercular drugs to fight with this deadly pathogen. Increasing resistance, adverse effects and costly treatment by conventional therapeutic agents have been inclining the researchers to search for an alternative source of medicine. In this regard natural compounds have been exploited extensively for their therapeutic interventions targeting cellular machinery of MTB. Glutamate racemase (MurI) is an enzyme involved in peptidoglycan (PG) biosynthesis and has become an attractive target due to its moonlighting property. We screened various classes of natural compounds using computational approach for their binding to MTB-MurI. Shortlisted best docked compounds were evaluated for their functional, structural and anti-mycobacterial activity. The results showed that two flavonoids (naringenin and quercetin) exhibited best binding affinity with MTB-MurI and inhibited the racemization activity with induced structural perturbation. In addition, fluorescence and electron microscopy were employed to confirm the membrane and cell wall damages in mycobacterial cells on exposure to flavonoids. Together, these observations could provide impetus for further research in better understanding of anti-tubercular mechanisms of flavonoids and establishing them as lead molecules for TB treatment.

Genital self-mutilation (GSM) is a much rare finding and more commonly associated with psychosis when it comes to comparison with self-mutilation as a whole. There have been anecdotal case reports of GSM in psychotic disorders with most of them being in long standing psychoses. We describe herein a case of GSM during the first episode of psychosis where multiple phenomenological variables were seen responsible for the act.

BACKGROUND Neuroendocrine biomarkers have long been studied in the context of electroconvulsive therapy (ECT). We prospectively assessed serum oxytocin change and moderators thereof in an exploratory study of patients receiving ECT. METHODS Serum oxytocin concentrations were assessed immediately before and 1 to 3 minutes after the first ECT in 33 patients with schizophrenia (n = 14), other nonaffective psychosis (n = 6), mania (n = 10), and depression (n = 3) who received 6 to 7 bitemporal, brief-pulse ECTs. Change in serum oxytocin was assessed in the sample as a whole, and as a function of age, sex, diagnosis, and treatment response. The primary outcome was change in serum oxytocin in the overall sample. RESULTS There was much variation across patients; oxytocin concentrations increased marginally by a mean (standard deviation) (M [SD]) of 6.4 (82.7) pg/mL (P = 0.43). The M (SD) change was -8.2 (85.0) pg/mL in patients with schizophrenia and other nonaffective psychoses (P = 0.84). There was no significant correlation between change in Brief Psychiatric Rating Scale scores and change in oxytocin concentrations in patients with schizophrenia, other nonaffective psychoses, and mania (ρ = 0.10, P = 0.61). Serum oxytocin rose in men, after ECT, and fell in women (P = 0.01). CONCLUSIONS Change in serum oxytocin immediately after the first ECT in a course may not be a useful biomarker of ECT action. This is the first report on the subject in a sample comprising mostly patients with nonaffective psychosis and mania rather than depression. We discuss our findings in the light of previous research and offer general conclusions about the field.