Sökning: WFRF:(Jayaraman Srimathi)
> (2007-2009) >
Intrinsic halotoler...
Intrinsic halotolerance of the psychrophilic alpha-amylase from Pseudoalteromonas haloplanktis
-
- Srimathi, Soundararajan (författare)
- Lund University,Lunds universitet,Tillämpad biokemi,Centrum för tillämpade biovetenskaper,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Pure and Applied Biochemistry,Center for Applied Life Sciences,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH
-
Jayaraman, Gurunathan (författare)
-
Feller, Georges (författare)
-
visa fler...
-
- Danielsson, Bengt (författare)
- Lund University,Lunds universitet,Tillämpad biokemi,Centrum för tillämpade biovetenskaper,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Pure and Applied Biochemistry,Center for Applied Life Sciences,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH
-
Narayanan, Paranji R. (författare)
-
visa färre...
-
(creator_code:org_t)
- 2007-02-20
- 2007
- Engelska.
-
Ingår i: Extremophiles. - : Springer Science and Business Media LLC. - 1433-4909 .- 1431-0651. ; 11:3, s. 505-515
- Relaterad länk:
-
http://dx.doi.org/10...
-
visa fler...
-
https://lup.lub.lu.s...
-
https://doi.org/10.1...
-
visa färre...
Abstract
Ämnesord
Stäng
- The halotolerance of a cold adapted alpha-amylase from the psychrophilic bacterium Pseudoalteromonas haloplanktis (AHA) was investigated. AHA exhibited hydrolytic activity over a broad range of NaCl concentrations (0.01-4.5 M). AHA showed 28% increased activity in 0.5-2.0 M NaCl compared to that in 0.01 M NaCl. In contrast, the corresponding mesophilic (Bacillus amyloliquefaciens) and thermostable (B. licheniformis) alpha-amylases showed a 39 and 46% decrease in activity respectively. Even at 4.5 M NaCl, 80% of the initial activity was detected for AHA, whereas the mesophilic and thermostable enzymes were inactive. Besides an unaltered fluorescence emission and secondary structure, a 10 degrees C positive shift in the temperature optimum, a stabilization factor of > 5 for thermal inactivation and a Delta T-m of 8.3 degrees C for the secondary structure melting were estimated in 2.7 M NaCl. The higher activation energy, half-life time and T-m indicated reduced conformational dynamics and increased rigidity in the presence of higher NaCl concentrations. A comparison with the sequences of other halophilic alpha-amylases revealed that AHA also contains higher proportion of small hydrophobic residues and acidic residues resulting in a higher negative surface potential. Thus, with some compromise in cold activity, psychrophilic adaptation has also manifested halotolerance to AHA that is comparable to the halophilic enzymes.
Ämnesord
- NATURVETENSKAP -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)
- NATURAL SCIENCES -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)
Nyckelord
- halotolerance
- halophilic
- acidic protein
- Pseudoalteromonas haloplanktis alpha-amylase
- psychrophilic
- stability
Publikations- och innehållstyp
- art (ämneskategori)
- ref (ämneskategori)
Hitta via bibliotek
Till lärosätets databas