Oral probiotics in coronavirus disease 2019: connecting the gut-lung axis to viral pathogenesis, inflammation, secondary infection and clinical trials.

Defined as helpful live bacteria that can provide medical advantages to the host when administered in tolerable amounts, oral probiotics might be worth considering as a possible preventive or therapeutic modality to mitigate coronavirus disease 2019 (COVID-19) symptom severity. This hypothesis stems from an emerging understanding of the gut-lung axis wherein probiotic microbial species in the digestive tract can influence systemic immunity, lung immunity, and possibly viral pathogenesis and secondary infection co-morbidities. We review the principles underlying the gut-lung axis, examples of probiotic-associated antiviral activities, and current clinical trials in COVID-19 based on oral probiotics.

Whole genome mining reveals a diverse repertoire of lanthionine synthetases and lanthipeptides among the genus Paenibacillus.

AIM: Lanthionine or methyllanthionine-containing lanthipeptides belongs to ribosomally synthesized and post-translationally modified peptides (RiPPs) family. Recent revolution in sequencing has made available huge genome sequence dataset of micro-organisms. In this study, we performed genome mining of the complete and partial genome sequences of 479 bacteria of the genus Paenibacillus to determine the diversity and distribution of lanthipeptide gene clusters. METHODS AND RESULTS: All genome sequences were annotated by RAST and subsequently analysed by BAGEL and antiSMASH. A total of 221 lanthipeptide gene clusters were identified in 127 strains of the genus Paenibacillus. One hundred and fifty gene clusters were found associated with the production of class I lanthipeptides while 58 and 13 gene clusters were related to class II and class IV lanthipeptide production respectively. Frequency of strains whose genomes encode putative lanthipeptide precursors was 26·5%. CONCLUSIONS: The results of lanthionine synthetases analysis suggested that diversity of lanthipeptides is much more than anticipated, while lanthionine synthetases must have been co-evolved among various species of the genus Paenibacillus. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report showing diversity and distribution of different classes of lanthipeptides among various species of the genus Paenibacillus. This study also reveals the novel lanthipeptide sequences which may be further developed as potential antimicrobials for therapeutic applications.