Search

Long fascinating to biologists, viruses offer nanometer-scale benchtops for building molecular-scale devices and materials. Viruses tolerate a wide range of chemical modifications including reaction conditions, pH values, and temperatures. Recent examples of nongenetic manipulation of viral surfaces have extended viruses into applications ranging from biomedical imaging, drug delivery, tissue regeneration, and biosensors to materials for catalysis and energy generation. Chemical reactions on the phage surface include both covalent and noncovalent modifications, including some applied in conjunction with genetic modifications. Here, we survey viruses chemically augmented with capabilities limited only by imagination.

Virus electrodes address two major challenges associated with biosensing. First, the surface of the viruses can be readily tailored for specific, high affinity binding to targeted biomarkers. Second, the viruses are entrapped in a conducting polymer for electrical resistance-based, quantitative measurement of biomarker concentration. To further enhance device sensitivity, two different ligands can be attached to the virus surface, and increase the apparent affinity for the biomarker. In the example presented here, the two ligands bind to the analyte in a bidentate binding mode with a chelate-based avidity effect, and result in a 100 pM experimentally observed limit of detection for the cancer biomarker prostate-specific membrane antigen. The approach does not require enzymatic amplification, and allows reagent-free, real-time measurements. This article presents general protocols for the development of such biosensors with modified viruses for the enhanced detection of arbitrary target proteins.

M13 bacteriophage display presents polypeptides as fusions to phage coat proteins. Such phage-displayed ligands offer useful reagents for biosensors. Here, we report a modified phage propagation protocol for the consistent and robust display of two different genetically encoded ligands on the major coat protein, P8. The results demonstrate that the phage surface reaches a saturation point for maximum peptide display.

The young minds of today are seen to have multiple behavioural issues which weren't so rampant in the past. Most of these problems in the daily lives of adolescents are said to be due to lack of empathetic skills and a definitive absence of being grateful for the resources they have. As psychologists, we make an attempt at enhancing empathy and gratitude among adolescents to inculcate pro-social behaviour. Empathy involves understanding, perceiving the situation from another person's perspective and these two together are essential traits in order to comprehend prosocial behavior. Gratitude is feeling thankful of what one has and feeling optimistic about what life has offered. Prosocial behavior is a voluntary behaviour to benefit others. The main objective of this study was to under stand the effect of empathy and gratitude on pro-social behaviour among Indian adolescents. The sample for the said study had 120 adolescents within the agebracket of 15-17 years. 60 out of these belonged to a nuclear family and 60 were from joint families. The tools used were Empathy Situational Test, GQ-6 and PTM-R. Scoring and statistical analysis followed and it was found that there is a significant effect of gratitude and empathy on pro-social behaviour. The results also showed that gender had a significant difference where males scored higher than females and there was no significant difference in terms of family type as a predictor of pro-social behaviour in the current study. The study emphasizes on further work in this topic and a strong need for the counsellors in schools and parents to take part in effective utilization of resources and improving positive behaviours in children. [ABSTRACT FROM AUTHOR]