Article (Scientific journals)
Purification and Characterization of the Heat-Labile Alpha-Amylase Secreted by the Psychrophilic Bacterium Tac 240b
Chessa, Jean-Pierre; Feller, Georges; Gerday, Charles
1999In Canadian Journal of Microbiology, 45 (6), p. 452-7
Peer Reviewed verified by ORBi
 

Files


Full Text
CanJMicro_1999_Chessa.pdf
Publisher postprint (364.36 kB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Abstract :
[en] A total of 59 bacteria samples from Antarctic sea water were collected and screened for their ability to produce alpha-amylase. The highest activity was recorded from an isolate identified as an Alteromonas species. The purified alpha-amylase shows a molecular mass of about 50,000 Da and a pI of 5.2. The enzyme is stable from pH 7.5 to 9 and has a maximal activity at pH 7.5. Compared with other alpha-amylases from mesophiles and thermophiles, the "cold enzyme" displays a higher activity at low temperature and a lower stability at high temperature. The psychrophilic alpha-amylase requires both Cl- and Ca2+ for its amylolytic activity. Br- is also quite efficient as an allosteric effector. The comparison of the amino acid composition with those of other alpha-amylases from various organisms shows that the cold alpha-amylase has the lowest content in Arg and Pro residues. This could be involved in the principle used by the psychrophilic enzyme to adapt its molecular structure to the low temperature of the environment.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Chessa, Jean-Pierre
Feller, Georges ;  Université de Liège - ULiège > Département des sciences de la vie > Labo de biochimie
Gerday, Charles ;  Université de Liège - ULiège > Services généraux (Faculté des sciences) > Relations académiques et scientifiques (Sciences)
Language :
English
Title :
Purification and Characterization of the Heat-Labile Alpha-Amylase Secreted by the Psychrophilic Bacterium Tac 240b
Publication date :
June 1999
Journal title :
Canadian Journal of Microbiology
ISSN :
0008-4166
eISSN :
1480-3275
Publisher :
NRC Research Press, Canada
Volume :
45
Issue :
6
Pages :
452-7
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 26 January 2010

Statistics


Number of views
105 (8 by ULiège)
Number of downloads
3 (1 by ULiège)

Scopus citations®
 
38
Scopus citations®
without self-citations
37
OpenCitations
 
26

Bibliography


Similar publications



Contact ORBi