Glucose Uptake Rate of Microorganisms Living in Hot Springs above 70°c Temperature:A Study of Panamik and Puga Hot Springs in the Ladakh Region, Jammu and Kashmir, India

This study measures in situ microbial glucose uptake rate in two different hot springs in Ladakh, J&K, India with distinct temperatures >74°C and pH > 7.4. For this purpose, the slurry samples from each hot spring were incubated up to 4 h with ¹³C-labelled glucose in gas-tight incubation bottles at the respective hot-spring sites. The natural δ¹³C particulate varies from –9.1‰ in Panamik hot spring to –11.7‰ in Puga hot spring. After incubation with ¹³C-labelled glucose, the δ¹³C particulate reached a maximum 2472‰ in Panamik and 4365‰ in Puga hot-spring samples. The glucose uptake rate calculated from the final δ¹³C particulate in the incubation bottles varied from 28 to 147 ng C g^–1 h^–1 in the Panamik and from 168 to 1196 ng C g^–1 h^–1 in the Puga samples. This reveals that even at >74°C temperature, thermophiles are capable of running their metabolic machinery, perhaps faster than the heterotrophic microbes/cells under normal temperature condition.