Please use this identifier to cite or link to this item:
Title: Studies on structural stability of thermophilic Sulfolobus acidocaldarius ribosomes
Authors: Yangala, Kalavathi
Suryanarayana, Tangirala
Keywords: Sulfolobus acidocaldarius;E. coli;RNase A;Archaeal ribosomes;Polyamines;Sulfhydryl reagents;Structural organization;Thermal stability
Issue Date: Feb-2007
Publisher: CSIR
Abstract: Structural stability of thermophilic archaeon Sulfolobus acidocaldarius ribosomes, with respect their susceptibility to pancreatic RNase A and stability to temperature (ΔTm), on treatment with various stabilizing (polyamines) and destabilizing (sulfhydryl and intercalating) agents were studied and compared with mesophilic E. coli ribosomes, to understand the structural differences between thermophilic and mesophilic ribosomes. Thermophilic archaeal ribosomes and their subunits were 10-times less susceptible to pancreatic RNase A, compared to mesophilic ribosomes, showing the presence of strong and compact structural organization in them. Thermophilic ribosomes treated with destabilizing agents, such as sulfhydryl reagents [5,5’-Dithio-bis-(2-nitrobenzoic acid), N-ethylmaleimide and p-hydroxymercurybenzoate) and intercalating agents (ethidium bromide, EtBr) showed higher stability to RNase A, compared to similarly treated mesophilic ribosomes, indicating the unavailability of thiol-reactive groups and the presence of strong solvent inaccessible inner core. Higher stability of thermophilic ribosomes compared to mesophilic ribosomes to unfolding agents like urea further supported the presence of strong inner core particle. Thermophilic ribosomes treated with intercalating agents, such as EtBr were less susceptible to RNase A, though they bound to more reagent, showing the rigidity or resilience of their macromolecular structure to alterations caused by destabilizing agents. Overall, these results indicated that factors such as presence of strong solvent inaccessible inner core and rigidity of ribosome macromolecular structure contributed stability of thermophilic ribosomes to RNase A and other destabilizing agents, when compared to mesophilic ribosomes.
Page(s): 19-25
ISSN: 0301-1208
Appears in Collections:IJBB Vol.44(1) [February 2007]

Files in This Item:
File Description SizeFormat 
IJBB 44(1) (2007) 19-25.pdf339.88 kBAdobe PDFView/Open

Items in NOPR are protected by copyright, with all rights reserved, unless otherwise indicated.