Halophilic properties of metal binding protein characterized by high histidine content from Chromohalobacter salexigens DSM3043.
Periplasmic metal binding protein characterized by high histidine content was cloned from moderate halophile, Chromohalobacter salexigens. The protein, termed histidine-rich metal binding protein (HP), was expressed in and purified from E. coli as a native form. HP bound to Ni- and Cu-loaded chelate columns with high affinity, and Co- and Zn-columns with moderate affinity. Although the secondary structure was not grossly altered by the addition of 0.2-2.0 M NaCl, the thermal transition pattern was considerably shifted to higher temperature with increasing salt concentration: melting temperature was raised by ~20 °C at 2.0 M NaCl over the melting temperature at 0.2 M NaCl. HP showed reversible refolding from thermal melting in 0.2-1.15 M NaCl, while it formed irreversible aggregates upon thermal melting at 2 M NaCl. Addition of 0.01-0.1 mM NiSO₄ stabilized HP against thermal melting with high reversibility, while addition above 0.5 mM resulted in irreversible melting due to aggregation.
Biochemistry and Applied Biosciences, The United Graduate School of Agricultural Sciences, Kagoshima University, Korimoto, Kagoshima, Japan.
Rui
R
Yamaguchi
Tsutomu
T
Arakawa
Hiroko
H
Tokunaga
Matsujiro
M
Ishibashi
Masao
M
Tokunaga
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055353:Chromohalobacter / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D006219:Halogens / Q000378:metabolism*; D006639:Histidine / Q000737:chemistry / Q000378:metabolism*; D006358:Hot Temperature; D008969:Molecular Sequence Data; D009532:Nickel / Q000737:chemistry / Q000378:metabolism*; D033902:Periplasmic Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D011489:Protein Denaturation; D058849:Protein Refolding; D055550:Protein Stability; D058767:Protein Unfolding; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012462:Saline Solution, Hypertonic / Q000737:chemistry; D016415:Sequence Alignment; D000099053:Histidine-Rich Glycoprotein
D001426:Bacterial Proteins; D006219:Halogens; D033902:Periplasmic Binding Proteins; D011506:Proteins; D011994:Recombinant Proteins; D012462:Saline Solution, Hypertonic; D000099053:Histidine-Rich Glycoprotein; C029938:nickel sulfate; D006639:Histidine; D003300:Copper; D009532:Nickel