Samragni Bhattacharyya

Nitrogen is one of the essential plant nutrients and a major factor limiting crop productivity. To meet the requirements of sustainable agriculture, there is a need to maximize biological nitrogen fixation in different crop species. Legumes are able to establish root nodule symbiosis (RNS) with nitrogen-fixing soil bacteria which are collectively called rhizobia. This mutualistic association is highly specific, and each rhizobia species/strain interacts with only a specific group of legumes, and vice versa. Nodulation involves multiple phases of interactions ranging from initial bacterial attachment and infection establishment to late nodule development, characterized by a complex molecular signalling between plants and rhizobia. Characteristically, legumes like groundnut display a bacterial invasion strategy popularly known as “crack-entry’’ mechanism, which is reported approximately in 25% of all legumes. This article accommodates critical discussions on the bacterial infection mo...

The occurrence of SARS-CoV-2 in 2019 is the second coronavirus spread-out after the SARS-CoV, which has pandemic potential. Search for its remedies is dependent on integrative knowledge of cell signaling pathways, which is under clinical scrutiny. The major cascades triggered by coronavirus entry include Renin-Angiotensin System, MAPK, NF-κB, JAK/STAT which are involved with innate immunity. Some other modes are, unfolded protein response signaling and inflammasome mediated apoptosis activation. Virulence factors of the SARS-CoVs like spike, envelope, nonstructural proteins etc., interfere with some of these viral defense pathways. Therapeutically, the viral intrusion, multiplication, as well as tissue-injurious cytokine overreactions are targeted by pathway-specific drugs. Viral entry blockers, p38 MAPK inhibitors, cytokine regulators, JAK inhibitors, and anti-inflammatory drugs are either being repurposed or innovated with scopes for futuristic modeling. This chapter is aimed to elucidate the pathological signaling network behind Severe Acute Respiratory Syndrome, for evaluation of existing and postulated drug targets.