Surface enhanced Raman spectroscopy based analysis of SARS-CoV-2 spike protein binding to ACE2 receptor

The SARS-CoV-2 virus is still a challenge because of its diversity and mutations. The binding interactions of the angiotensin converting enzyme 2 (ACE2) receptor and the spike protein are relevant for the SARS-CoV-2 virus to enter the cell. Consequently, it is important and helpful to analyze binding activities and the changes in the structure of the ACE2 receptor and the spike protein. Surface enhanced Raman spectroscopy is able to analyze small concentrations of the proteins without contact, non-invasively and label-free. In this work, we present a SERS based approach in the visible wavelength range to analyze and study the binding interactions of the ACE2 receptor and the spike protein. SERS measurements of the ACE2 receptor, the spike protein and the ACE2-spike complex were performed. Additionally, an inhibitor was used to prevent the spike protein from binding to ACE2 and to compare the results. The analysis of the measured SERS spectra reveals structural differences and changes due to binding activities. Thus, we show that the performed SERS based approach can help for rapid and non-invasive analysis of binding interactions of the ACE2-spike complex and also of protein binding in general. © 2023 SPIE.

Covid-19 and repercussions in mental health: a narrative review of literature

OBJECTIVE: To identify the repercussions on mental health of groups and populations in the context of the new coronavirus pandemic. METHOD: Narrative review carired out in three databases, in March 2020, using the descriptors mental health and coronavirus. A total of 19 publications were analyzed, organized in a synoptic chart, containing type of publication, authors, country, sample, objective, and main results. From this analysis, two thematic axes emerged: identification of problems and vulnerable groups in mental health;and mental health interventions and actions. RESULTS: The first axis showed manifestations of suffering - anguish, insomnia, anger, stress, fear. The second revealed the need to build government policies and general guidelines;production of information and communication;and mental health care practices. CONCLUSIONS: The repercussions on mental health in the population intensified with the pandemic, identifying vulnerable groups, and the need to build coping strategies and policies aimed at mental health during epidemics.