Growth response and protein profile of two different Scytonema species from cave walls and soil crusts in light and dark
Kumari Samad, Lakshmi; Rath, Jnanendra; Prasad Adhikary, Siba
The growth pattern of two species of Scytonema, S. coactile and S. stuposum, isolated from the twilight zone of a cave and from a soil crust, respectively was studied under different light and dark regimes. The organism from the cave showed a better growth capability at the lower light intensity of 2.5 W .m-2, and utilized several exogenous sugars for its chemoheterotrophic as well as mixotrophic growth. To the contrary, S. stuposum from the soil crust grew well at a higher light intensity of 7.5 W .m-2 and did not grow in the dark utilizing exogenous sugars except fructose and mannose, showing that substrate specificity and efficiency of substrate utilization vary from species to species and also under light and dark regime. S. stuposum induced several proteins for mixotrophic and heterotrophic growth in the presence of fructose whereas S. coactile did not require induction of any protein for growth in darkness as it was adapted to grow in such a habitat in the cave.