ABSTRACT
Bacterial diversity of four thermally different hot springs of Ratnagiri district, Maharashtra, India, was investigated using culture-dependent and culture-independent approaches. A total of 144 bacterial cultures were isolated and identified using MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) and 16S rRNA gene sequencing. Culture-independent analysis by Ion Torrent sequencing targeting the V3 region of the 16S rRNA gene revealed the predominance of Firmicutes across all the hot springs, followed by Chloroflexi, Bacteroidetes, Cyanobacteria, Proteobacteria, Armatimonadetes, Actinobacteria, Nitrospirae, Acidobacteria, and Deinococcus-Thermus, with subtle differences in their abundance. At the lower taxonomic rank of genus, we noted the prevalence of Acinetobacter followed by Clostridium, Planomicrobium, Bacillus, Streptomyces, and Leptolyngbya. Metagenomics imputation using in silico approach revealed divergence in the metabolic capabilities of bacterial communities along the thermal gradient of host springs, with site TS (63 °C) featuring the abundant functional gene families.
Subject(s)
Cyanobacteria , Hot Springs , Humans , India , Phylogeny , RNA, Ribosomal, 16S/geneticsABSTRACT
BACKGROUND: The development of antivirals against herpes simplex virus 2 (HSV-2) has a major public health importance because of the wide spectrum of associated clinical disease in both immunocompetent and immunocompromised populations. Even with the extensive use of acyclovir, issues such as emergence of drug-resistant strains, poor oral bioavailability and low effectiveness in recurrent infections have highlighted the requirement for alternate therapies. Plants, which are rich in metabolites and active against viruses, are being explored as one such source. We had earlier reported specific and potent anti-HSV-2 activity from the roots of the plant Indigofera heterantha. Herein, we describe the mechanism by which it exerts this antiviral potential against HSV-2. METHODS: MTT, plaque reduction and immunofluorescence techniques were used for in vitro antiviral studies. Animal studies were carried out in HSV-2-infected mice followed by plaque reduction assays. RESULTS: The extract was found to act at multiple steps of viral entry viz attachment, adsorption and penetration by blocking binding sites present on the viral envelope glycoproteins which eventually blocks its binding with the cell surface receptors present on the host cells. We also showed efficacy of PP9706642 topical application in prohibiting HSV-2 invasion to nearby organs from the site of infection, that is vagina in HSV-2 infected animals. CONCLUSIONS: The extract targets the early and late stages of HSV-2 viral life cycle and thus shows great promise as both a prophylactic as well as therapeutic phytopharmaceutical against HSV-2.