EpCSP from Exiguobacterium profundum confers enhanced stress tolerance and adaptive resilience in heterologous systems

The cold shock protein EpCSP from Exiguobacterium profundum was characterized for its role in enhancing abiotic stress tolerance in transgenic tobacco. The gene, encoding a conserved RNA-binding protein, was cloned from Exiguobacterium profundum and expressed in tobacco, resulting in improved drought and cold resilience. Under drought conditions, transgenic lines exhibited a 1.4-fold higher relative water content and chlorophyll levels, along with a 30% reduction in malondialdehyde (MDA) content, increased superoxide dismutase activity, and enhanced proline accumulation. In response to cold stress, transgenic seedlings achieved 80% germination-1.45-fold higher than wild-type-and retained 1.7- to 1.8-fold more chlorophyll, accompanied by reduced MDA levels and elevated antioxidant capacity. EpCSP conferred stress tolerance by stabilizing membranes, enhancing photosynthetic efficiency, and activating osmoprotective mechanisms. This study underscores the potential of EpCSP as a valuable tool for engineering stress-resilient crops to sustain productivity under adverse climatic conditions.