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Infection prevention and control (IPC) program is obligatory for delivering quality services in any healthcare setup. Lack of administrative support and resource-constraints (under-staffing, inadequate funds) were primary barriers to successful implementation of IPC practices in majority of the hospitals in the developing countries. The Coronavirus Disease 2019 (COVID-19) brought a unique opportunity to improve the IPC program in these hospitals. A PDSA (Plan-Do-Study- Act) model was adopted for this study in a tertiary care hospital which was converted into a dedicated COVID-19 treatment facility in Varanasi, India. The initial focus was to identify the deficiencies in existing IPC practices and perceive the opportunities for improvement. Repeated IPC training (induction and reinforce) was conducted for the healthcare personnel (HCP) and practices were monitored by direct observation and closed-circuit television. Cleaning audits were performed by visual inspection, review of the checklists and qualitative assessment of the viewpoints of the HCP was carried out by the feedbacks received at the end of the training sessions. A total of 2552 HCP and 548 medical students were trained in IPC through multiple offline/onsite sessions over a period of 15 months during the ongoing pandemic. Although the overall compliance to surface disinfection and cleaning increased from 50% to >80% with repeated training, compliance decreased whenever newly recruited HCP were posted. Fear psychosis in the pandemic was the greatest facilitator for adopting the IPC practices. Continuous wearing of personal protective equipment for long duration, dissatisfaction with the duty rosters as well as continuous posting in high-risk areas were the major obstacles to the implementation of IPC norms. Recognising the role of an infection control team, repeated training, monitoring and improvisation of the existing resources are keys for successful implementation of IPC practices in hospitals during the COVID-19 pandemic., Competing Interests: The authors have declared that no competing interests exist.

Background: The ribosome, which acts as a platform for mRNA encoded polypeptide synthesis, is also capable of assisting in folding of polypeptide chains. The peptidyl transferase center (PTC) that catalyzes peptide bond formation resides in the domain V of the 23S rRNA of the bacterial ribosome. Proper positioning of the 3' -CCA ends of the A- and P-site tRNAs via specific interactions with the nucleotides of the PTC are crucial for peptidyl transferase activity. This RNA domain is also the center for ribosomal chaperoning activity. The unfolded polypeptide chains interact with the specific nucleotides of the PTC and are released in a folding competent form. In vitro transcribed RNA corresponding to this domain (bDV RNA) also displays chaperoning activity., Results: The present study explores the effects of tRNAs, antibiotics that are A- and P-site PTC substrate analogs (puromycin and blasticidin) and macrolide antibiotics (erythromycin and josamycin) on the chaperoning ability of the E. coli ribosome and bDV RNA. Our studies using mRNA programmed ribosomes show that a tRNA positioned at the P-site effectively inhibits the ribosome's chaperoning function. We also show that the antibiotic blasticidin (that mimics the interaction between 3'-CCA end of P/P-site tRNA with the PTC) is more effective in inhibiting ribosome and bDV RNA chaperoning ability than either puromycin or the macrolide antibiotics. Mutational studies of the bDV RNA could identify the nucleotides U2585 and G2252 (both of which interact with P-site tRNA) to be important for its chaperoning ability., Conclusion: Both protein synthesis and their proper folding are crucial for maintenance of a functional cellular proteome. The PTC of the ribosome is attributed with both these abilities. The silencing of the chaperoning ability of the ribosome in the presence of P-site bound tRNA might be a way to segregate these two important functions.

Background: Molecular chaperones that support de novo folding of proteins under non stress condition are classified as chaperone 'foldases' that are distinct from chaperone' holdases' that provide high affinity binding platform for unfolded proteins and prevent their aggregation specifically under stress conditions. Ribosome, the cellular protein synthesis machine can act as a foldase chaperone that can bind unfolded proteins and release them in folding competent state. The peptidyl transferase center (PTC) located in the domain V of the 23S rRNA of Escherichia coli ribosome (bDV RNA) is the chaperoning center of the ribosome. It has been proposed that via specific interactions between the RNA and refolding proteins, the chaperone provides information for the correct folding of unfolded polypeptide chains., Results: We demonstrate using Escherichia coli ribosome and variants of its domain V RNA that the ribosome can bind to partially folded intermediates of bovine carbonic anhydrase II (BCAII) and lysozyme and suppress aggregation during their refolding. Using mutants of domain V RNA we demonstrate that the time for which the chaperone retains the bound protein is an important factor in determining its ability to suppress aggregation and/or support reactivation of protein., Conclusion: The ribosome can behave like a 'holdase' chaperone and has the ability to bind and hold back partially folded intermediate states of proteins from participating in the aggregation process. Since the ribosome is an essential organelle that is present in large numbers in all living cells, this ability of the ribosome provides an energetically inexpensive way to suppress cellular aggregation. Further, this ability of the ribosome might also be crucial in the context that the ribosome is one of the first chaperones to be encountered by a large nascent polypeptide chains that have a tendency to form partially folded intermediates immediately following their synthesis.