2. Salt stress is the most severe environmental abiotic stress.
Organisms which withstand against this situation are called halophilic
organisms .and others are called non halophilic.
They sense and adapt to hypersaline condition such that their protein
machinary also require high salt for their native form.
The secret of salinity tolerance capability of halotolerant proteins
is due to the presence of more no. of negatively charged acidic
residues at their surface which are having the capacity of binding
to the salt ions very effectively through electrostatic interaction.
Odisha NET Academy -09337727724
3. To choose one model organism growing in
hypersaline condition .
To choose one halophilic protein from that
organism.
To find out whether that particular protein
survivivg during salinity condition in other
halotolerant species or not through in-silico
comparative proteomics analysis .
Odisha NET Academy -09337727724
4. H.salinarum was chosen as the model organism from a list of no. of
halotolerant species on the basis of its salt stress tolerating capability.
This microbe is an extreme halophile survives in world’s most salted
environment, the dead sea. It can tolerate upto 4.5 M NaCl or higher.
Colour of the dead sea looks purple or reddish colour due to high
density of these halo archaeons.
Odisha NET Academy -09337727724
5. Ferredoxin was detected as a halophilic protein from H.salinarum
through various article search.
Ferredoxin is an ubiqutous electron transferring protein involving in
various metabolic reactions diversely found among almost all
organisms also surviving as a halophilic protein in an extreme
haloarcheon Halobacterium salinarum .
Odisha NET Academy -09337727724
6. NCBI
BLAST
CLUSTAL X2
MEGA 5.0
MODELLER 9.10
PYTHON 2.7
I-TASSER SERVER
RAMPAGE SERVER
MODLOOP SERVER
YASARA MINIMIZATION SERVER
DISCOVERY STUDIO 3.0
Odisha NET Academy -09337727724
15. SOFTWARES USED : MODELLER 9.10 , PYTHON 2.7,
ClustalX2
Input files for modeller :
PDB file of known structure(.pdb)
Alignment file of target and template(.ali)
Python script file for generating model(.py)
Odisha NET Academy -09337727724
34. Protein structure enhances protein
function
As we got the proof for structural
conservedness for ferredoxin protein
among these species ,it is expected
that somehow this protein survives
during salinity condition not only
in H.salinarum, but also in other
microbes and plant species which we
have detected as halotolerant
species. Odisha NET Academy -09337727724
35. R.H. Reed, in: R.A. Herbert, G.A. Codd (Eds.) Microbes in extreme environments, Special publications for
the Society for General Microbiology, Academic Press, London, 17, 1986, pp. 51.
L.D. Mermelstein, J.G. Zeikus in: Edited by K. Horikoshi, W.D. Grant (Eds.) Extremophiles. Microbial life
in extreme environments, Wiley-Liss, New York, 1998.
Frolow, F., Harel, M., Sussman, J.L., Mevarech, M., Shoham, M. Insights into protein adaptation to a
saturated salt environment from the crystal structure of a halophilic 2Fe–2S ferredoxin. Nat. Struct.
Biol. 1996;3:452–458.
Halobacterium salinarum. Membrane Biochemistry Dieter Oesterhelt. Max
PlanckinstituteofBiochemistry.10/22/2011. http://mnphys.biochem.mpg.de/en/eg/oesterhelt/web_page_list/
Org_Hasal/index.html/
Ishibashi, M., Tokunaga, H., Hiratsuka, K., Yonezawa, Y., Turumaru, H., Arakawa, T., Tokunaga, M.
NaCl-activated nucleoside diphosphate kinase from extremely halophilic archaeon,Halobacterium
salinarum, maintain native conformation without salt. FEBS Lett.2001;493:134–138.
Electrostatic contribution to the stability of halophilic proteinBandyopadhyay AK, Krishnamoorthy G,
Sonawat HM (2001) Structural stabilization of [2Fe–2S] ferredoxin from Halobacterium salinarum.
Biochemistry 40:1284–1292
Schweimer K, Marg B-L, Oesterhelt D, Rosch P, Sticht H (2000) Sequence-specific 1H, 13C and 15N
resonance assignments and secondary structure of [2Fe–2S] ferredoxin from Halobacterium salinarum. J
Biomol NMR 16:347–348
. Werber MM, Mevarech M (1978) Purification and characterization of a highly acidic 2Fe–2S ferredoxin
from Halobacterium of the Dead Sea. Arch Biochem Biophys 187:447–456
Marg B-L, Schweimer K, Sticht H, Oesterhelt D (2005) A two-a-helix extra domain mediates the halophilic
character of a plant type ferredoxin from halophilic archaea. Biochemistry 44:29–39
Odisha NET Academy -09337727724
