Differential scanning calorimetric studies of a Bacillus halodurans alpha-amylase
(2005) In Biochimica et Biophysica Acta. General Subjects 1723(1-3). p.184-191- Abstract
- The thermal unfolding of Amy 34, a recombinant alpha-amylase from Bacillus halodurans, has been investigated using differential scanning calorimetry (DSC). The denaturation of Amy 34 involves irreversible processes with an apparent denaturation temperature (T-m) of 70.8 degrees C at PH 9.0, with four transitions, as determined using multiple Gaussian curves. The T-m increased by 5 degrees C in the presence of 100-fold molar excess of CaCl2 while the aggregation of Amy 34 was observed in the presence of 1000-fold molar excess of CaCl2. Increase in the calcium ion concentration from 1 - to 5-fold molar excess resulted in an increase in calorimetric enthalpy (Delta H-cal), however, at higher concentrations of CaCl2 (up to 100-fold), Delta... (More)
- The thermal unfolding of Amy 34, a recombinant alpha-amylase from Bacillus halodurans, has been investigated using differential scanning calorimetry (DSC). The denaturation of Amy 34 involves irreversible processes with an apparent denaturation temperature (T-m) of 70.8 degrees C at PH 9.0, with four transitions, as determined using multiple Gaussian curves. The T-m increased by 5 degrees C in the presence of 100-fold molar excess of CaCl2 while the aggregation of Amy 34 was observed in the presence of 1000-fold molar excess of CaCl2. Increase in the calcium ion concentration from 1 - to 5-fold molar excess resulted in an increase in calorimetric enthalpy (Delta H-cal), however, at higher concentrations of CaCl2 (up to 100-fold), Delta H-cal was found to decrease, accompanied by a decrease in entropy change (Delta S), while the T., steadily increased. The presence of 100-fold excess of metal chelator, EDTA, resulted in a decrease in T-m by 10.4 degrees C. T-m was also decreased to 61.1 degrees C and 65.9 degrees C at PH 6.0 and PH 11.0, respectively. (c) 2005 Elsevier B.V. All rights reserved. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/155153
- author
- Hashim, Suhaila LU ; Hatti-Kaul, Rajni LU ; Andersson, Maria LU ; Mulaa, F J and Mattiasson, Bo LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biochimica et Biophysica Acta. General Subjects
- volume
- 1723
- issue
- 1-3
- pages
- 184 - 191
- publisher
- Elsevier
- external identifiers
-
- wos:000229691900021
- pmid:15826839
- scopus:19744371497
- ISSN
- 0304-4165
- DOI
- 10.1016/j.bbagen.2005.03.004
- language
- English
- LU publication?
- yes
- id
- 26b85e4c-547c-479c-a260-879fa74985c7 (old id 155153)
- date added to LUP
- 2016-04-01 16:59:54
- date last changed
- 2022-03-15 04:27:33
@article{26b85e4c-547c-479c-a260-879fa74985c7, abstract = {{The thermal unfolding of Amy 34, a recombinant alpha-amylase from Bacillus halodurans, has been investigated using differential scanning calorimetry (DSC). The denaturation of Amy 34 involves irreversible processes with an apparent denaturation temperature (T-m) of 70.8 degrees C at PH 9.0, with four transitions, as determined using multiple Gaussian curves. The T-m increased by 5 degrees C in the presence of 100-fold molar excess of CaCl2 while the aggregation of Amy 34 was observed in the presence of 1000-fold molar excess of CaCl2. Increase in the calcium ion concentration from 1 - to 5-fold molar excess resulted in an increase in calorimetric enthalpy (Delta H-cal), however, at higher concentrations of CaCl2 (up to 100-fold), Delta H-cal was found to decrease, accompanied by a decrease in entropy change (Delta S), while the T., steadily increased. The presence of 100-fold excess of metal chelator, EDTA, resulted in a decrease in T-m by 10.4 degrees C. T-m was also decreased to 61.1 degrees C and 65.9 degrees C at PH 6.0 and PH 11.0, respectively. (c) 2005 Elsevier B.V. All rights reserved.}}, author = {{Hashim, Suhaila and Hatti-Kaul, Rajni and Andersson, Maria and Mulaa, F J and Mattiasson, Bo}}, issn = {{0304-4165}}, language = {{eng}}, number = {{1-3}}, pages = {{184--191}}, publisher = {{Elsevier}}, series = {{Biochimica et Biophysica Acta. General Subjects}}, title = {{Differential scanning calorimetric studies of a Bacillus halodurans alpha-amylase}}, url = {{http://dx.doi.org/10.1016/j.bbagen.2005.03.004}}, doi = {{10.1016/j.bbagen.2005.03.004}}, volume = {{1723}}, year = {{2005}}, }