Two novel phages PSPa and APPa inhibit planktonic, sessile and persister populations of Pseudomonas aeruginosa, and mitigate its virulence in Zebrafish model.

The present study explores the avenue of phage therapy as an alternative antimicrobial therapeutic approach to counter multidrug-resistant (MDR) Pseudomonas aeruginosa infection. Our study investigated two novel virulent phages PSPa and APPa, specific to P. aeruginosa, in which in vitro evaluations were carried out to assess the therapeutic potential of phages. Both the identified phages exhibited host specificity by showing antagonistic activity of about 96.43% (27/28) and 92.85% (26/28) towards the 28 MDR clinical isolates of P. aeruginosa. The PSPa phage was found to have linear dsDNA with a sequence length of 66,368 bp and 92 ORFs, of which 32 were encoded for known functions of the phage life cycle and the remaining 60 were hypothetical functions. The APPa phage was found to have linear dsDNA with 59,591 bp of genome length and 79 ORFs, of which 15 were found to have known phage functions and the remaining 64 were found to be hypothetical proteins. Notably, the genome of both the phages lacks genes coding for tRNA, rRNA, and tmRNA. The phylogenetic analysis revealed that PSPa and APPa share > 95% sequence similarity with previously sequenced Pseudomonas viruses of their respective families. Further, the in vivo efficacy evaluation using the zebrafish model revealed that the treatment with PSPa and APPa has remarkably improved the survival rate of bacterial-infected zebrafish, reinforcing the anti-infective potential of the isolated phages PSPa and APPa against P. aeruginosa infection.

CRISPR based bacterial genome editing and removal of pathogens.

Engineering nucleases to achieve targeted genome editing has turned out to be a revolutionary means for manipulating the genetic content in diversified living organisms. For targeted genome editing, till to date, only three engineered nucleases exist viz. zinc finger nucleases, transcription activator-like effector nucleases and RNA-mediated nucleases (RGNs) (Cas nucleases) from the clustered regularly interspaced short palindromic repeat (CRISPR). Among, Cas9 nuclease has been considered as a simplest tool for efficient modification of endogenous genes in an extensive stretch of organisms, owing to its amenability to design guide RNA compatible to the sequence of new targets. Moreover, CRISPR/Cas system delivers a multipurpose RNA-guided DNA-targeting platform called as CRISPR interference (CRISPRi), as well as epigenetic modifications and high throughput screening in diverse organism including bacteria, all in a sequence explicit way. With these entire advancements, the present chapter illustrates the deployment of CRISPR/Cas9 in bacterial genome editing and removal of pathogens.

Promising phytochemicals of traditional Indian herbal steam inhalation therapy to combat COVID-19 - An in silico study.

BACKGROUND: COVID-19, the presently prevailing global public health emergency has culminated in international instability in economy. This unprecedented pandemic outbreak pressingly necessitated the trans-disciplinary approach in developing novel/new anti-COVID-19 drugs especially, small molecule inhibitors targeting the seminal proteins of viral etiological agent, SARS-CoV-2. METHODS: Based on the traditional medicinal knowledge, we made an attempt through molecular docking analysis to explore the phytochemical constituents of three most commonly used Indian herbs in 'steam inhalation therapy' against well recognized viral receptor proteins. RESULTS: A total of 57 phytochemicals were scrutinized virtually against four structural protein targets of SARS-CoV-2 viz. 3CLpro, ACE-2, spike glycoprotein and RdRp. Providentially, two bioactives from each of the three plants i.e. apigenin-o-7-glucuronide and ellagic acid from Eucalyptus globulus; eudesmol and viridiflorene from Vitex negundo and; vasicolinone and anisotine from Justicia adhatoda were identified to be the best hit lead molecules based on interaction energies, conventional hydrogen bonding numbers and other non-covalent interactions. On comparison with the known SARS-CoV-2 protease inhibitor -lopinavir and RdRp inhibitor -remdesivir, apigenin-o-7-glucuronide was found to be a phenomenal inhibitor of both protease and polymerase, as it strongly interacts with their active sites and exhibited remarkably high binding affinity. Furthermore, in silico drug-likeness and ADMET prediction analyses clearly evidenced the usability of the identified bioactives to develop as drug against COVID-19. CONCLUSION: Overall, the data of the present study exemplifies that the phytochemicals from selected traditional herbs having significance in steam inhalation therapy would be promising in combating COVID-19.

Global multi-omics and systems pharmacological strategy unravel the multi-targeted therapeutic potential of natural bioactive molecules against COVID-19: An in silico approach.

Understanding the immunological behavior of COVID-19 cases at molecular level is essential for therapeutic development. In this study, multi-omics and systems pharmacology analyses were performed to unravel the multi-targeted mechanisms of novel bioactives to combat COVID-19. Immuno-transcriptomic dataset of healthy controls and COVID-19 cases was retrieved from ArrayExpress. Phytocompounds from ethnobotanical plants were collected from PubChem. Differentially expressed 98 immune genes associated with COVID-19 were derived through NetworkAnalyst 3.0. Among 259 plant derived compounds, 154 compounds were targeting 13 COVID-19 immune genes involved in diverse signaling pathways. In addition, pharmacological properties of these phytocompounds were compared with COVID-19 drugs prescribed by WHO, and 25 novel phytocompounds were found to be more efficient with higher bioactive scores. The current study unravels the virogenomic signatures which can serve as therapeutic targets and identified phytocompounds with anti-COVID-19 efficacy. However, further experimental validation is essential to bring out these molecules as commercial drug candidates.