The precursor of a psychrophilic alpha-amylase: structural characterization and insights into cold adaptation.
The alpha-amylase precursor from the bacterium Pseudoalteromonas haloplanktis possesses a propeptide at the C-terminus possibly responsible for outer membrane translocation. Unlike the predicted beta-barrel of autotransporters, this C-terminal propeptide displays a noticeable alpha-helix content. It is connected to the enzyme by a disordered linker and has no significant interaction with the catalytic domain. The microcalorimetric pattern of the precursor also demonstrates that the stability of protein domains may evolve differently.
Claverie
Paule
P
Laboratoire de Biochimie, Institut de Chimie B6, Université de Liège, B-4000, Liège, Sart Tilman, Belgium.
Vigano
Catherine
C
Ruysschaert
Jean-Marie
JM
Gerday
Charles
C
Feller
Georges
G
D000064:Acclimatization; D002152:Calorimetry, Differential Scanning; D003080:Cold Temperature; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D011487:Protein Conformation; D011498:Protein Precursors / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D017434:Protein Structure, Tertiary; D031161:Pseudoalteromonas / Q000201:enzymology*; D017550:Spectroscopy, Fourier Transform Infrared; D000516:alpha-Amylases / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics
D011498:Protein Precursors; D000516:alpha-Amylases